most unethical experiments of all time

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The 10 Cruelest Human Experimentation Cases in History

“First, do no harm,” is the oath taken by physicians the world over. And this has been the case for centuries now. For the most part, these men and women of science stay faithful to this oath, even defying orders to the contrary. But sometimes they not only break it, they do so in the worst way imaginable. There have been numerous instances of doctors and other scientists going way beyond the limitations of what’s moral or ethical in the name of ‘progress’. They have used humans as experimental guinea pigs for their tests.

In many cases, the test subjects were either kept in ignorance about what an experiment involved or they were simply in no position to offer their resistance or consent. Of course, it may well be the case that such dubious methods produced results. Indeed, some of the most controversial experiments of the past century produced results that continue to inform scientific understanding to this day. But that will never mean such experiments will be seen as just. Sometimes, the perpetrators of cruel research lose their good names or reputations. Sometimes they are prosecuted for their attempts to ‘play God’. Or sometimes they just get away with it.

You might want to brace yourself as we look at the ten weirdest and cruelest human experiments carried out in history:

Dr. Shiro Ishii and Unit 731

During World War II, Imperial Japan committed a number of crimes against humanity. But perhaps few were crueler than the experiments that were conducted at Unit 731. Part of the Imperial Japanese Army, this was a super-secret unit dedicated to undertaking research into biological and chemical weapons. Quite simply, the Imperial authority wanted to build weapons that were deadlier – or just crueler – than anything that had gone before. And they weren’t opposed to using human guinea pigs to test their creations.

Based in Harbon, the biggest city of Manchuko, the part of north-east China that Japan made its puppet state, Unit 731 was constructed between 1934 and 1939. Overseeing its construction was General Shiro Ishii. Though he was a medical doctor, Ishii was also a fanatical soldier and so he was happy to set his ethics aside in the name of total victory for Imperial Japan. In all, it’s estimated that as many as 3,000 men, women and children were used as forced participants in the experiments conducted here. For the most part, the horrific tests were carried out on Chinese people, though prisoners-of-war, including men from Korea and Mongolia, were used.

For more than five years, General Ishii oversaw a wide range of experiments, many of them of dubious medical value to say the least. Thousands were subjected to vivisections, usually without anaesthetic. Often, these were fatal. Countless types of surgery, including brain surgery and amputations, were also carried out without anaesthetic. At other times, inmates were injected directly with diseases such as syphilis and gonorrhoea, or with chemicals used in bombs. Other twisted experiments included tying men up naked outside and observing the effects of frostbite, or simply starving people and seeing how long they took to die.

Once it was clear Japan was going to lose the war, General Ishii tried to destroy all evidence of the tests. He burned down the facilities and swore his men to silence. He needn’t have worried. Senior researchers from Unit 731 were granted immunity by the U.S. In exchange, they contributed their knowledge to America’s own biological and chemical weapons programs. For decades, any stories of atrocities were dismissed as ‘Communist Propaganda’. In more recent years, the Japanese government has acknowledged the Unit’s existence as well as its work, though it maintains most official records have been lost to history.

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“The Little Albert Experiment”

After many months observing young children, John Hopkins University psychologist Dr. John B. Watson concluded that infants could be conditioned to be scared of non-threatening objects or stimuli. All he needed was first-hand proof. Since it was 1919 and experimental ethics were nowhere near as strict as they are today, Watson, along with his graduate student Rosalie Rayner, set about designing an experiment to test their theory. Thanks to their connections at the Baltimore hospital, they were able to find a young baby, named ‘Albert’, and ‘borrow’ him for the afternoon. While Albert’s mother might have consented to her son helping out scientific research, she had no idea what Watson was actually planning.

The young Albert was just nine months old when he was taken from a hospital and put to work as Watson’s guinea pig. At first, Watson carried out a series of baseline tests, to see that the child was indeed emotionally stable and at the accepted stage of development. But then the tests got creepier. Albert was shown several furry animals. These included a dog, a white rat and a rabbit. Watson would show these toys to Albert while at the same time banging a hammer against a metal bar. This was repeated a number of times. Before long, Albert was associating the sight of the furry animals with the fear provoked by the loud, unpleasant noise. Indeed, within just a short space of time, just seeing the furry rat could distress the child.

Watson noted at the time: “The instant the rat was shown, the baby began to cry. Almost instantly he turned sharply to the left, fell over on [his] left side, raised himself on all fours and began to crawl away so rapidly that he was caught with difficulty before reaching the edge of the table.” The scientist and his research partner had achieved their goal: they had proof that, just as in animals, classical conditioning can be used to influence or even dictate emotional responses in humans. Watson published his findings the following year, in the prestigious Journal of Experimental Psychology .

Even at the time, Watson’s methods were seen as unethical. After all, isn’t a doctor supposed to ‘do no harm’? What’s more, Watson never worked with Little Albert again, so he wasn’t able to reverse the process. But still, the results were heralded as a breakthrough in our understanding of popular psychology. Notably, Watson recorded the Little Albert Experiment, and the videos can be seen online today. And, for what it’s worth, most experts now agree that, though he would have most likely feared furry objects for a short spell of time during his childhood, Little Albert probably lost the association between cute toys and loud noises.

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The “Monster” Study

These days, any tests carried out on children are subject to strict ethical rules and guidelines. This wasn’t the case back in the 1930s, however. So, when Wendell Johnson, a speech pathologist at the University of Iowa, wanted to carry out research on young participants, his institution was happy to oblige. Along with Mary Tudor, a grad student Johnson was supervising, work began in 1939. Over the next few years, dozens of kids would be subject to speech-related tests, with the effects of the experiment lasting for decades.

The purpose of the research sounded noble enough: Johnson wanted to see how a child’s upbringing affects their speech. In particular, he was fascinated by stuttering and determined to see what made one child stutter, yet another speak fluently. Thankfully, a local orphanage was able to ‘supply’ Johnson and Tudor with 22 children for them to work with. All of the young participants spoke without a stutter when they arrived at the University of Iowa labs for the first time. They were then divided into two equal groups, and the experiment got underway.

Both groups were asked to speak for the researchers. How they were treated, however, was completely different. In the first group, all of the children received positive feedback. They were praised for their fluent speech and command of the English language. The second group received the opposite kind of treatment. They were ridiculed for their inability to speak like adults. Johnson and Tudor would listen carefully for any little mistakes, and above all for any signs of stuttering, and criticize the children harshly for them.

Johnson’s methods shocked his academic peers. Not that they would have been so surprised. As a young researcher at the University of Iowa, he gained a reputation for experimenting with shock tactics. For instance, as a postgraduate student himself, Johnson would work with his colleagues trying to cure his own stutter, even electrocuting himself to see if that made a difference. But still, inflicting deliberate cruelty on children was seen as a step too far. As such, the Iowan academics nicknamed Johnson’s 1939 research ‘The Monster Study’. And the name was just about the only thing of significance it gave us.

With the University of Iowa keen to distances itself from news of human experimentation being carried out by the Nazis in war-torn Europe, they hushed-up the Monster Study. None of the findings were ever published in any academic journal of note. Only Johnson’s own thesis remains. The effects were clear, however. Many of the children in the second group went on to develop serious stutters. Some even had serious speech problems for the rest of their lives. The university finally acknowledged the experiment in 2001, apologising to those involved. Then, in 2007, six of the original orphan kids were awarded almost $1 million in compensation for the psychological impact Johnson’s work had on them.

Interestingly, however, while the methods used for the Monster Study have widely been condemned as being cruel and simply indefensible, some have argued that Johnson may have been onto something. Certainly, Mary Tudor said before her death that she and her research partner might have made serious contributions to our understanding of speech and speech pathology had they been allowed to publish their work. Instead, the experiment is now shorthand for bad science and a complete lack of ethics.

The Stanford Prison Experiment

Off all the ill-advised – and indeed, cruel – experiments North American universities have carried out over the decades, none is more infamous than the Stanford Prison Experiment. It’s so famous, in fact, that movies have been made based on the experiment which took place at Stanford University for one week in August 1971. Furthermore, while undoubtedly cruel, its findings are still used to inform popular understanding of psychological manipulation. Moreover, the behaviour of the participants involved is often held up as a warning about what can happen if humans are given power without accountability.

The experiment was led by Professor Phillip Zimbrano. As a psychologist, he was eager to see whether abuse in prisons can be explained by the inherent psychological traits of both guards and prisoners. Given the topic, he received funding from the U.S. Office of Naval Research. Funding in hand, Zimbrano set about recruiting participants. This turned out to be no problem at all, as a number of Stanford students volunteered to take part. Zimbrano then appointed some of the volunteers as guards and the others were designated as prisoners. The experiment could begin.

In the basement of the university’s psychology department, Zimbrano had built a makeshift ‘prison’. In all, 12 prisoners were kept here in small cells, while 12 guards were assigned a different part of the basement. While the prisoners had to endure tough conditions, the guards enjoyed comfortable, furnished quarters. The participants were also dressed for their parts, with the guards given uniforms and wooden batons. They were also kitted out with dark sunglasses so they could avoid eye contact with the people they were tasked with guarding.

Within 24 hours, any semblance of calm had gone. The prisoners started to revolt and the guards started to react. Special cells were set up to give well-behaving prisoners preferential treatment. The guards – who were barred from actually physically hitting their charges – started to use psychological methods to keep prisoners down. They would deny them food or put prisoners in darkened cells. Sleep was also denied to the prisoners. Within six days, Zimbrano agreed to halt the experiment. He did, at least, have more than enough evidence – some of it filmed – to draw on when making his conclusions.

Professor Zimbrano noted that around one third of the guards – again, young men taken randomly from the Stanford student population – exhibited genuine sadistic tendencies. At the same time, most of the inmates were seen to ‘internalise’ their roles. They took on the mentality of prisoners. While they could have left at any time, they instead gave up and became weak and passive. In the end, the experiment received, and continues to receive, criticism for the harsh methods used. Nevertheless, the findings of the Stanford Prison Experiment actually changed the way U.S. prisons are run and they are often held up as proof that most people can inflict cruelty and suffering on another human being if they are given a position of power and ordered to do so.

The South African ‘Aversion Project’

In Apartheid-era South Africa, national service was compulsory for all white males. At the same time, homosexuality was classed as a crime. Inevitably, therefore, any gay men who found themselves called into service were in for a tough time. But it wasn’t just name-calling or casual discrimination they had to contend with. Many were subjected to cruel experiments. The so-called ‘Aversion Project’, run throughout the 1970s and then the 1980s, was aimed at ‘treating’ homosexuals. As well as psychological treatments, it also used physical ‘treatments’, many of which would rightly be regarded as torture.

The project first really got started in 1969, with the creation of Ward 22. The creepily-named ward was part of a larger military hospital just outside of Pretoria and was designed to treat mentally-ill soldiers. For the unit chief Dr Aubrey Levin, this including homosexuals, regarded as unstable, or even ‘deviants’. For the most part, the doctor was determined to prove that electric shock therapy and conditioning could ‘cure’ the patients of their desires. Hundreds of men were electrocuted, often while being forced to look at pictures of gay men. The electric current would then be turned off and pictures of naked women shown instead in the hope that this would alter the mindset.

Inmates subjected to such experimental treatment would sometimes be tested, given temptations to see if they really were ‘cured’. Persistent ‘offenders’ were given hormone treatments, almost always against their will, and many were even chemically castrated. Even by the middle of the 1970s, when numerous, more ethical, studies had proven that ‘conversion therapies’ could change a person’s sexuality, Ward 22 carried on with its work. In fact, in only ended with the fall of the apartheid regime. To the very end of the project, Dr Levin maintained that all the men he treated were volunteers and asked for his help. Many of his peers disagreed, as did a judge, who sentenced him to five years in prison in 2014.

Project 4.1

On March 1, 1954, the United States carried out Castle Bravo , testing a nuclear bomb on the Bikini Atoll, in the middle of the Pacific Ocean. The test not only went without a hitch, it actually went better than expected. The yield produced by the bomb was much higher than scientists had anticipated. At the same time, the weather conditions in this part of the Pacific turned out to be different to what had been predicted. Radiation fallout from the blast was blown upwind, towards the Marshall Islands. But, instead of alerting the islanders to the danger, the project heads sensed an opportunity. How many times would they be able to see the affect of radiation fallout on a population for real?

Making the most of the opportunity, the American scientists simply sat back an observed. That is, they watched innocent people be affected by the fallout of an American nuclear bomb. Over the next decade, the project observers noted an upturn in the number of women on the Marshall Islands suffering miscarriages or stillbirths. But then, after ten years or so, this spike ended. Things seemingly returned to normal, and so scientists were unable – or unwilling – to make any formal conclusions. But then, things started to go downhill again.

At first, children on the Marshall Islands were observed to be growing less than would be expected. But then, it became clear that not only were they suffering from stunted growth, but a higher-than-expected proportion of youngsters were developing thyroid cancer. What’s more, by 1974, the data was showing that one in three islanders had developed at least one tumor. Later analysis, published in 2010, estimated that around half of all cancer cases recorded on the Marshall Islands could be attributed to the 1954 nuclear test, even if people never displayed any obvious signs of radiation poisoning in the immediate aftermath of the explosion.

Given that the initial findings of Project 4.1 as it was known were published in professional medical journals as early as 1955, the American government has never really denied that the experiment took place. Rather, what has been, and continues to be contested, is whether the U.S. actually knew that the islands would be affected before they carried out the test. Many on the Marshall Islands believe that Project 4.1 was premeditated, while the American authorities maintain that it was improvised in the wake of the explosion. The debate continues to rage.

The Tuskegee Experiments

For four decades, African-American men in Macon County, Alabama, were told by medical researchers that they had ‘bad blood’. The scientists knew that this was a term used by sharecroppers in this part of the country to refer to a wide range of ailments. They knew, therefore, that they wouldn’t question the prognosis. And neither would they raise any concerns or questions when the same researchers gave them injections. Which is how doctors working on behalf of the U.S. Public Health Service (PHS) were able to look on as hundreds of men went mad, blind or even died as a result of untreated syphilis.

When the experiment began back in 1932, there was no known cure for syphilis. As such, PHS researchers were determined to make a breakthrough. They went to Tuskegee College in Alabama and enlisted their help. Together, they enlisted 622 African-American men, almost all of them very poor. Of these men, 431 had already contracted syphilis prior to 1932, with the remaining 169 free from the disease. The men were told that the experiment would last for just six years, during which time they would be provided with free meals and medical care as doctors observed the development of the disease.

In 1947, penicillin became the recommended treatment for syphilis. Surely the doctors would give this to the men participating in the Tuskegee Experiment? Not so. Even though they knew the men could be cured, the PHR workers only gave them placebos, including aspirin and even combinations of minerals. With their condition untreated, the men slowly succumbed to syphilis. Some went blind, others went insane, and some died within a few years. What’s more, in the years after 1947, 19 syphilitic children were born to men enrolled in the study.

It was only in the mid-1960s that concerns started to be raised about the morality of the experiment. San Francisco-based PHS researcher Peter Buxton learned about what was happening in Alabama and raised his concerns. However, his superiors were unresponsive. As a result, Buxton leaked the story to a journalist friend. The story broke in 1972. Unsurprisingly, the public were outraged. The experiment was halted immediately, and the Congress inquiries began soon after. The surviving participants, as well as the children of those men who had died, were awarded $10 million in an out-of-court settlement. Finally, in 1993, President Bill Clinton offered a formal and official apology on behalf of the U.S. government to everyone affected by the experiment.

Project MK-Ultra

Though they had the Bomb, in the 1950s, the CIA were still determined to enjoy every advantage over their enemies. To achieve this, they were willing to think outside of the box. Perhaps the best example of this was MK-Ultra, a top-secret project where the CIA attempted to alter brain function and explore the possibility of mind control. While much of the written evidence, including files and witness testimonies, were destroyed soon after the experiments were brought to an end, we do know that the project involved a lot of drugs, some sex and countless instances of rule bending and breaking.

Project MK-Ultra was kick-started by the Office of Scientific Experiments at the start of the 1950s. Central to the project was determining how LSD affects the mind – and, more importantly, whether this could be turned to America’s advantage. In order to learn more, hundreds, perhaps even thousands of individuals, were given doses of the drug. In almost all cases, they were given LSD without their explicit knowledge or consent. For example, during Operation Midnight Climax in the early 1960s, the CIA opened up brothels. Here, the male clients were dosed up with LSD and then observed by scientists through one-way mirrors.

The experiments also included subjecting American citizens to sleep deprivation and hypnosis. Not all of the tests went plainly. Several people died as a direct result of Project MK-Ultra, including a US Army biochemist by the name of Frank Olsen. In 1953, the scientist was given a dose of LSD without his knowledge and, just a week later, died after jumping out of a window. While the official reason of his death was recorded as suicide, Olsen’s family have always maintained that he was effectively killed by the CIA.

When President Gerald Ford launched a special Commission on CIA activities in the United States, the work of Project MK-Ultra came to light. Two years previously, however, the-then Director of the CIA, Richard Helms, had ordered all files relating to the experiments to be destroyed. Witness testaments show that around 80 institutions were involved in the experiments, with thousands of people given hallucinogenic drugs, usually by CIA officers with no medical background. And so, in the end, was it all worth it? The CIA has acknowledged that the experiments produced nothing of real, scientific value. Project MK-Ultra has, however, lived on in the popular imagination and has inspired numerous books, video games and movies.

Guatemalan Syphilis Experiment

For more than two years in the middle of the 20 th century, the United States worked directly with the health ministries of Guatemala to infect thousands of people with a range of sexually transmitted diseases, above all syphilis. Since they wanted to do this without the study subjects knowing about it – after all, who would give their consent to being injected with syphilis? – it was decided that the experiment should take place in Guatemala, with soldiers and the most vulnerable members of society to serve as the guinea pigs.

The Guatemalan Syphilis Experiment (it was not given an official codename or even a formal project title) began in 1946. It was headed up by John Charles Cutler of the US Public Health Service (PHS). Despite being a physician himself, Cutler was happy to overlook the principle of ‘First, do no harm’ in order to carry out his work. Making use of local health clinics, he tasked his staff with infecting around 5,500 subjects. Most of them were soldiers or prisoners, though mental health patients and prostitutes were also used to see how syphilis and other diseases affect the body. Children living in orphanages were even used for the experiments.

In all cases, the subjects were told they were getting medication that was good for them. And, while all subjects were given antibiotics, an estimated 83 people died. In 1948, with the wider medical community hearing rumors of what was being done in Central America, and with the American government wary of the potential fallout, the experiments were brought to an abrupt end. Cutler would go on to carry out similar experiments in Alabama, though even here he stopped short of actually infecting his subjects with life-threatening diseases.

It was only in 2010, however, that the United States government issued a formal apology to Guatemala for the experiments it carried out in the 1940s. What’s more, President Barack Obama called the project “a crime against humanity”. That didn’t mean that the victims could get compensation, however. In 2011, several cases were put forward but then rejected, with the presiding judge noting that the U.S. government could not be held liable for actions carried out in its name outside of the country. A $1 billion lawsuit against the John Hopkins University and against the Rockefeller Foundation is still open.

Mengele’s Twins

A world at war gave the Nazi regime the ideal cover under which they would carry out some of the most horrific human experiments imaginable. At Auschwitz concentration camp, Dr Josef Mengele made full use of the tens of thousands of prisoners available to him. He would carry out unnecessarily cruel and unusual experiments, often with little or no scientific merit. And, above all, he was fascinated with twins. Or, more precisely, with identical twins. These would be the subjects of his most gruesome experiments.

Mengele would personally select prospective subjects from the ramps leading off the transport trains at the entrance to the concentration camp. Initially, his chosen twins were provided with relatively comfortable accommodation, as well as more generous rations than the rest of the inmate population. However, this was just a temporary respite. Mengele’s experiments were as varied as they were horrific. He would amputate one twin’s limbs and then compare the growth of both over the following days. Or he would infect one twin with a disease like typhoid. When they died, he would kill the healthy twin, too, and then compare their bodies.

Gruesomely, the records show that on one particularly bloody night, Mengele injected chloroform directly into the heart of 14 sets of twins. All died almost immediately. Another infamous tale tells of Mengele trying to create his own conjoined twins: he simply stitched two young Romani children back-to-back. They both died of gangrene after several long and painful days. Mengele also had a team of assistants working for him, and they were no less cruel.

Nobody will ever know just how many children or adults were victims of Mengele’s experiments. Despite being meticulous record keepers, the Nazis kept some things secret. Tragically for his victims and their relatives, Mengele never faced justice for his actions. He was smuggled out of Europe by Nazi sympathisers at the end of the war and lived for another 30 years, in hiding, in South America.

Where did we find this stuff? Here are our sources:

“Unmasking Horror: A special report.; Japan Confronting Gruesome War Atrocity”. Nicholas D. Kristof, The New York Times, 1995.

“Little Albert regains his identity”. American Psychology Association, 2010.

“Unit 731: Japan discloses details of notorious chemical warfare division”. Justin McCurry, The Guardian, April 2018.

“The Stuttering Doctor’s ‘Monster Study'”. Gretchen Reynolds, The New York Times, March 2003.

“The Real Lesson of the Stanford Prison Experiment” . Maria Konnikova, The New Yorker, June 2015.

“Gays tell of mutilation by apartheid army” . Chris McGreal, The Guardian, July 2000.

“Nuclear Savage: The Islands of Secret Project 4.1” . The Environment & Society Portal.

“Tuskegee Experiment: The Infamous Syphilis Study” . Elizabeth Nix, History.com, May 2017.

“The secret LSD-fuelled CIA experiment that inspired Stranger Things” . Richard Vine, The Guardian, August 2016.

“Guatemala victims of US syphilis study still haunted by the ‘devil’s experiment'” . Rory Carroll, The Guardian, June 2011.

“Nazi Medical Experiments” . The United States Holocaust Memorial Museum.

• 20 Most Unethical Experiments in Psychology

Humanity often pays a high price for progress and understanding — at least, that seems to be the case in many famous psychological experiments. Human experimentation is a very interesting topic in the world of human psychology. While some famous experiments in psychology have left test subjects temporarily distressed, others have left their participants with life-long psychological issues . In either case, it’s easy to ask the question: “What’s ethical when it comes to science?” Then there are the experiments that involve children, animals, and test subjects who are unaware they’re being experimented on. How far is too far, if the result means a better understanding of the human mind and behavior ? We think we’ve found 20 answers to that question with our list of the most unethical experiments in psychology .

Emma Eckstein

Electroshock Therapy on Children

Operation Midnight Climax

The Monster Study

Project MKUltra

The Aversion Project

Unnecessary Sexual Reassignment

Stanford Prison Experiment

Milgram Experiment

The Monkey Drug Trials

Featured Programs

Facial expressions experiment.

Little Albert

Bobo Doll Experiment

The Pit of Despair

The Bystander Effect

Learned Helplessness Experiment

Racism Among Elementary School Students

UCLA Schizophrenia Experiments

The Good Samaritan Experiment

Robbers Cave Experiment

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Controversial and Unethical Psychology Experiments

There have been a number of famous psychology experiments that are considered controversial, inhumane, unethical, and even downright cruel—here are five examples. Thanks to ethical codes and institutional review boards, most of these experiments could never be performed today.

At a Glance

Some of the most controversial and unethical experiments in psychology include Harlow's monkey experiments, Milgram's obedience experiments, Zimbardo's prison experiment, Watson's Little Albert experiment, and Seligman's learned helplessness experiment.

These and other controversial experiments led to the formation of rules and guidelines for performing ethical and humane research studies.

Harlow's Pit of Despair

Psychologist Harry Harlow performed a series of experiments in the 1960s designed to explore the powerful effects that love and attachment have on normal development. In these experiments, Harlow isolated young rhesus monkeys, depriving them of their mothers and keeping them from interacting with other monkeys.

The experiments were often shockingly cruel, and the results were just as devastating.

The Experiment

The infant monkeys in some experiments were separated from their real mothers and then raised by "wire" mothers. One of the surrogate mothers was made purely of wire.

While it provided food, it offered no softness or comfort. The other surrogate mother was made of wire and cloth, offering some degree of comfort to the infant monkeys.

Harlow found that while the monkeys would go to the wire mother for nourishment, they preferred the soft, cloth mother for comfort.

Some of Harlow's experiments involved isolating the young monkey in what he termed a "pit of despair." This was essentially an isolation chamber. Young monkeys were placed in the isolation chambers for as long as 10 weeks.

Other monkeys were isolated for as long as a year. Within just a few days, the infant monkeys would begin huddling in the corner of the chamber, remaining motionless.

The Results

Harlow's distressing research resulted in monkeys with severe emotional and social disturbances. They lacked social skills and were unable to play with other monkeys.

They were also incapable of normal sexual behavior, so Harlow devised yet another horrifying device, which he referred to as a "rape rack." The isolated monkeys were tied down in a mating position to be bred.

Not surprisingly, the isolated monkeys also ended up being incapable of taking care of their offspring, neglecting and abusing their young.

Harlow's experiments were finally halted in 1985 when the American Psychological Association passed rules regarding treating people and animals in research.

Milgram's Shocking Obedience Experiments

Isabelle Adam/Flickr/CC BY-NC-ND 2.0

If someone told you to deliver a painful, possibly fatal shock to another human being, would you do it? The vast majority of us would say that we absolutely would never do such a thing, but one controversial psychology experiment challenged this basic assumption.

Social psychologist Stanley Milgram conducted a series of experiments to explore the nature of obedience . Milgram's premise was that people would often go to great, sometimes dangerous, or even immoral, lengths to obey an authority figure.

The Experiments

In Milgram's experiment, subjects were ordered to deliver increasingly strong electrical shocks to another person. While the person in question was simply an actor who was pretending, the subjects themselves fully believed that the other person was actually being shocked.

The voltage levels started out at 30 volts and increased in 15-volt increments up to a maximum of 450 volts. The switches were also labeled with phrases including "slight shock," "medium shock," and "danger: severe shock." The maximum shock level was simply labeled with an ominous "XXX."​

The results of the experiment were nothing short of astonishing. Many participants were willing to deliver the maximum level of shock, even when the person pretending to be shocked was begging to be released or complaining of a heart condition.

Milgram's experiment revealed stunning information about the lengths that people are willing to go in order to obey, but it also caused considerable distress for the participants involved.

Zimbardo's Simulated Prison Experiment

 Darrin Klimek / Getty Images

Psychologist Philip Zimbardo went to high school with Stanley Milgram and had an interest in how situational variables contribute to social behavior.

In his famous and controversial experiment, he set up a mock prison in the basement of the psychology department at Stanford University. Participants were then randomly assigned to be either prisoners or guards. Zimbardo himself served as the prison warden.

The researchers attempted to make a realistic situation, even "arresting" the prisoners and bringing them into the mock prison. Prisoners were placed in uniforms, while the guards were told that they needed to maintain control of the prison without resorting to force or violence.

When the prisoners began to ignore orders, the guards began to utilize tactics that included humiliation and solitary confinement to punish and control the prisoners.

While the experiment was originally scheduled to last two full weeks it had to be halted after just six days. Why? Because the prison guards had started abusing their authority and were treating the prisoners cruelly. The prisoners, on the other hand, started to display signs of anxiety and emotional distress.

It wasn't until a graduate student (and Zimbardo's future wife) Christina Maslach visited the mock prison that it became clear that the situation was out of control and had gone too far. Maslach was appalled at what was going on and voiced her distress. Zimbardo then decided to call off the experiment.

Zimbardo later suggested that "although we ended the study a week earlier than planned, we did not end it soon enough."

Watson and Rayner's Little Albert Experiment

If you have ever taken an Introduction to Psychology class, then you are probably at least a little familiar with Little Albert.

Behaviorist John Watson  and his assistant Rosalie Rayner conditioned a boy to fear a white rat, and this fear even generalized to other white objects including stuffed toys and Watson's own beard.

Obviously, this type of experiment is considered very controversial today. Frightening an infant and purposely conditioning the child to be afraid is clearly unethical.

As the story goes, the boy and his mother moved away before Watson and Rayner could decondition the child, so many people have wondered if there might be a man out there with a mysterious phobia of furry white objects.

Controversy

Some researchers have suggested that the boy at the center of the study was actually a cognitively impaired boy who ended up dying of hydrocephalus when he was just six years old. If this is true, it makes Watson's study even more disturbing and controversial.

However, more recent evidence suggests that the real Little Albert was actually a boy named William Albert Barger.

Seligman's Look Into Learned Helplessness

During the late 1960s, psychologists Martin Seligman and Steven F. Maier conducted experiments that involved conditioning dogs to expect an electrical shock after hearing a tone. Seligman and Maier observed some unexpected results.

When initially placed in a shuttle box in which one side was electrified, the dogs would quickly jump over a low barrier to escape the shocks. Next, the dogs were strapped into a harness where the shocks were unavoidable.

After being conditioned to expect a shock that they could not escape, the dogs were once again placed in the shuttlebox. Instead of jumping over the low barrier to escape, the dogs made no efforts to escape the box.

Instead, they simply lay down, whined and whimpered. Since they had previously learned that no escape was possible, they made no effort to change their circumstances. The researchers called this behavior learned helplessness .

Seligman's work is considered controversial because of the mistreating the animals involved in the study.

Impact of Unethical Experiments in Psychology

Many of the psychology experiments performed in the past simply would not be possible today, thanks to ethical guidelines that direct how studies are performed and how participants are treated. While these controversial experiments are often disturbing, we can still learn some important things about human and animal behavior from their results.

Perhaps most importantly, some of these controversial experiments led directly to the formation of rules and guidelines for performing psychology studies.

Blum, Deborah.  Love at Goon Park: Harry Harlow and the science of affection . New York: Basic Books; 2011.

Sperry L.  Mental Health and Mental Disorders: an Encyclopedia of Conditions, Treatments, and Well-Being . Santa Barbara, CA: Greenwood, an imprint of ABC-CLIO, LLC; 2016.

Marcus S. Obedience to Authority An Experimental View. By Stanley Milgram. illustrated . New York: Harper &. The New York Times. 

Le Texier T. Debunking the Stanford Prison Experiment .  Am Psychol . 2019;74(7):823‐839. doi:10.1037/amp0000401

Fridlund AJ, Beck HP, Goldie WD, Irons G.  Little Albert: A neurologically impaired child .  Hist Psychol.  2012;15(4):302-27. doi:10.1037/a0026720

Powell RA, Digdon N, Harris B, Smithson C. Correcting the record on Watson, Rayner, and Little Albert: Albert Barger as "psychology's lost boy" .  Am Psychol . 2014;69(6):600‐611. doi:10.1037/a0036854

Seligman ME. Learned helplessness .  Annu Rev Med . 1972;23:407‐412. doi:10.1146/annurev.me.23.020172.002203

By Kendra Cherry, MSEd Kendra Cherry, MS, is a psychosocial rehabilitation specialist, psychology educator, and author of the "Everything Psychology Book."

10 Psychological Experiments That Could Never Happen Today

By meredith danko | sep 20, 2013.

Nowadays, the American Psychological Association has a Code of Conduct in place when it comes to ethics in psychological experiments. Experimenters must adhere to various rules pertaining to everything from confidentiality to consent to overall beneficence. Review boards are in place to enforce these ethics. But the standards were not always so strict, which is how some of the most famous studies in psychology came about. 

1. The Little Albert Experiment

At Johns Hopkins University in 1920, John B. Watson conducted a study of classical conditioning, a phenomenon that pairs a conditioned stimulus with an unconditioned stimulus until they produce the same result. This type of conditioning can create a response in a person or animal towards an object or sound that was previously neutral. Classical conditioning is commonly associated with Ivan Pavlov, who rang a bell every time he fed his dog until the mere sound of the bell caused his dog to salivate.

Watson tested classical conditioning on a 9-month-old baby he called Albert B. The young boy started the experiment loving animals, particularly a white rat. Watson started pairing the presence of the rat with the loud sound of a hammer hitting metal. Albert began to develop a fear of the white rat as well as most animals and furry objects. The experiment is considered particularly unethical today because Albert was never desensitized to the phobias that Watson produced in him. (The child died of an unrelated illness at age 6, so doctors were unable to determine if his phobias would have lasted into adulthood.)

2. Asch Conformity Experiments

Solomon Asch tested conformity at Swarthmore College in 1951 by putting a participant in a group of people whose task was to match line lengths. Each individual was expected to announce which of three lines was the closest in length to a reference line. But the participant was placed in a group of actors, who were all told to give the correct answer twice then switch to each saying the same incorrect answer. Asch wanted to see whether the participant would conform and start to give the wrong answer as well, knowing that he would otherwise be a single outlier.

Thirty-seven of the 50 participants agreed with the incorrect group despite physical evidence to the contrary. Asch used deception in his experiment without getting informed consent from his participants, so his study could not be replicated today.

3. The Bystander Effect

Some psychological experiments that were designed to test the bystander effect are considered unethical by today’s standards. In 1968, John Darley and Bibb Latané developed an interest in crime witnesses who did not take action. They were particularly intrigued by the murder of Kitty Genovese , a young woman whose murder was witnessed by many, but still not prevented.

The pair conducted a study at Columbia University in which they would give a participant a survey and leave him alone in a room to fill out the paper. Harmless smoke would start to seep into the room after a short amount of time. The study showed that the solo participant was much faster to report the smoke than participants who had the exact same experience, but were in a group.

The studies became progressively unethical by putting participants at risk of psychological harm. Darley and Latané played a recording of an actor pretending to have a seizure in the headphones of a person, who believed he or she was listening to an actual medical emergency that was taking place down the hall. Again, participants were much quicker to react when they thought they were the sole person who could hear the seizure.

4. The Milgram Experiment

Yale psychologist Stanley Milgram hoped to further understand how so many people came to participate in the cruel acts of the Holocaust. He theorized that people are generally inclined to obey authority figures, posing the question , “Could it be that Eichmann and his million accomplices in the Holocaust were just following orders? Could we call them all accomplices?” In 1961, he began to conduct experiments of obedience.

Participants were under the impression that they were part of a study of memory . Each trial had a pair divided into “teacher” and “learner,” but one person was an actor, so only one was a true participant. The drawing was rigged so that the participant always took the role of “teacher.” The two were moved into separate rooms and the “teacher” was given instructions. He or she pressed a button to shock the “learner” each time an incorrect answer was provided. These shocks would increase in voltage each time. Eventually, the actor would start to complain followed by more and more desperate screaming. Milgram learned that the majority of participants followed orders to continue delivering shocks despite the clear discomfort of the “learner.”

Had the shocks existed and been at the voltage they were labeled, the majority would have actually killed the “learner” in the next room. Having this fact revealed to the participant after the study concluded would be a clear example of psychological harm.

5. Harlow’s Monkey Experiments

In the 1950s, Harry Harlow of the University of Wisconsin tested infant dependency using rhesus monkeys in his experiments rather than human babies. The monkey was removed from its actual mother which was replaced with two “mothers,” one made of cloth and one made of wire. The cloth “mother” served no purpose other than its comforting feel whereas the wire “mother” fed the monkey through a bottle. The monkey spent the majority of his day next to the cloth “mother” and only around one hour a day next to the wire “mother,” despite the association between the wire model and food.

Harlow also used intimidation to prove that the monkey found the cloth “mother” to be superior. He would scare the infants and watch as the monkey ran towards the cloth model. Harlow also conducted experiments which isolated monkeys from other monkeys in order to show that those who did not learn to be part of the group at a young age were unable to assimilate and mate when they got older. Harlow’s experiments ceased in 1985 due to APA rules against the mistreatment of animals as well as humans . However, Department of Psychiatry Chair Ned H. Kalin, M.D. of the University of Wisconsin School of Medicine and Public Health has recently begun similar experiments that involve isolating infant monkeys and exposing them to frightening stimuli. He hopes to discover data on human anxiety, but is meeting with resistance from animal welfare organizations and the general public.

6. Learned Helplessness

The ethics of Martin Seligman’s experiments on learned helplessness would also be called into question today due to his mistreatment of animals. In 1965, Seligman and his team used dogs as subjects to test how one might perceive control. The group would place a dog on one side of a box that was divided in half by a low barrier. Then they would administer a shock, which was avoidable if the dog jumped over the barrier to the other half. Dogs quickly learned how to prevent themselves from being shocked.

Seligman’s group then harnessed a group of dogs and randomly administered shocks, which were completely unavoidable. The next day, these dogs were placed in the box with the barrier. Despite new circumstances that would have allowed them to escape the painful shocks, these dogs did not even try to jump over the barrier; they only cried and did not jump at all, demonstrating learned helplessness.

7. Robbers Cave Experiment

Muzafer Sherif conducted the Robbers Cave Experiment in the summer of 1954, testing group dynamics in the face of conflict. A group of preteen boys were brought to a summer camp, but they did not know that the counselors were actually psychological researchers. The boys were split into two groups, which were kept very separate. The groups only came into contact with each other when they were competing in sporting events or other activities.

The experimenters orchestrated increased tension between the two groups, particularly by keeping competitions close in points. Then, Sherif created problems, such as a water shortage, that would require both teams to unite and work together in order to achieve a goal. After a few of these, the groups became completely undivided and amicable.

Though the experiment seems simple and perhaps harmless, it would still be considered unethical today because Sherif used deception as the boys did not know they were participating in a psychological experiment. Sherif also did not have informed consent from participants.

8. The Monster Study

At the University of Iowa in 1939, Wendell Johnson and his team hoped to discover the cause of stuttering by attempting to turn orphans into stutterers. There were 22 young subjects, 12 of whom were non-stutterers. Half of the group experienced positive teaching whereas the other group dealt with negative reinforcement. The teachers continually told the latter group that they had stutters. No one in either group became stutterers at the end of the experiment, but those who received negative treatment did develop many of the self-esteem problems that stutterers often show. Perhaps Johnson’s interest in this phenomenon had to do with his own stutter as a child , but this study would never pass with a contemporary review board.

Johnson’s reputation as an unethical psychologist has not caused the University of Iowa to remove his name from its Speech and Hearing Clinic .

9. Blue Eyed versus Brown Eyed Students

Jane Elliott was not a psychologist, but she developed one of the most famously controversial exercises in 1968 by dividing students into a blue-eyed group and a brown-eyed group. Elliott was an elementary school teacher in Iowa, who was trying to give her students hands-on experience with discrimination the day after Martin Luther King Jr. was shot, but this exercise still has significance to psychology today. The famous exercise even transformed Elliott’s career into one centered around diversity training.

After dividing the class into groups, Elliott would cite phony scientific research claiming that one group was superior to the other. Throughout the day, the group would be treated as such. Elliott learned that it only took a day for the “superior” group to turn crueler and the “inferior” group to become more insecure. The blue eyed and brown eyed groups then switched so that all students endured the same prejudices.

Elliott’s exercise (which she repeated in 1969 and 1970) received plenty of public backlash, which is probably why it would not be replicated in a psychological experiment or classroom today. The main ethical concerns would be with deception and consent, though some of the original participants still regard the experiment as life-changing .

10. The Stanford Prison Experiment

In 1971, Philip Zimbardo of Stanford University conducted his famous prison experiment, which aimed to examine group behavior and the importance of roles. Zimbardo and his team picked a group of 24 male college students who were considered “healthy,” both physically and psychologically. The men had signed up to participate in a “ psychological study of prison life ,” which would pay them $15 per day. Half were randomly assigned to be prisoners and the other half were assigned to be prison guards. The experiment played out in the basement of the Stanford psychology department where Zimbardo’s team had created a makeshift prison. The experimenters went to great lengths to create a realistic experience for the prisoners, including fake arrests at the participants’ homes.

The prisoners were given a fairly standard introduction to prison life, which included being deloused and assigned an embarrassing uniform. The guards were given vague instructions that they should never be violent with the prisoners, but needed to stay in control. The first day passed without incident, but the prisoners rebelled on the second day by barricading themselves in their cells and ignoring the guards. This behavior shocked the guards and presumably led to the psychological abuse that followed. The guards started separating “good” and “bad” prisoners, and doled out punishments including push ups, solitary confinement, and public humiliation to rebellious prisoners.

Zimbardo explained , “In only a few days, our guards became sadistic and our prisoners became depressed and showed signs of extreme stress.” Two prisoners dropped out of the experiment; one eventually became a psychologist and a consultant for prisons . The experiment was originally supposed to last for two weeks, but it ended early when Zimbardo’s future wife, psychologist Christina Maslach, visited the experiment on the fifth day and told him , “I think it’s terrible what you’re doing to those boys.”

Despite the unethical experiment, Zimbardo is still a working psychologist today. He was even honored by the American Psychological Association with a Gold Medal Award for Life Achievement in the Science of Psychology in 2012 .

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Mad scientists: 10 most unethical social experiments gone horribly wrong.

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Curiosity is the fuel that drives social experiments performed in the world of science. Today, experiments must abide by the American Psychological Association’s (APA) Code of Conduct , which pertains to everything from confidentiality, to consent, to overall beneficence. However, the standards weren’t always so high. In their latest video , “10 Evil Social Experiments,” Alltime10s highlights the most famous and disturbing experiments that took place all around the world that could never happen today.

Adults, children, and even animals were a part of the inhumane practices of several mad scientists. In 1939, psychologist Wendell Johnson at the University of Iowa performed "The Monster Study," a stuttering experiment on 22 orphaned children. The children were divided into two groups. The first received positive speech therapy , in which the children's successes were praised. The other group had negative therapy and were told off for every mistake they made.

The effects on the children who had negative speech therapy were horrible. Their schoolwork suffered, their behavior became more timid, and they developed speech impediments. In 2007, six of the children were awarded $925,000 for life-long psychological damage.

In the 1970s to 1980s, during the Apartheid era, the South African army forced suspected gay and lesbian soldiers to undergo sex-change operations , chemical castrations, electrical shocks, and other forms of unethical medication, in an attempt to cure their illegal sexuality, which became known as “The Aversion Project.”

Inevitably, this became psychologically damaging to about 900 individuals who underwent reassignment operations carried out in military hospitals in South Africa throughout this period. The patients were abandoned, and often unable to pay for the hormones needed to maintain their new identity, leading some to commit suicide.

Animals could not escape the wrath of mad scientist Dr. Harry Harlow in his experiment “The Pit of Despair.” Harlow experimented on baby rhesus monkeys to study social interaction and isolation in the 1970s. He would select baby monkeys who had bonded with their mother and separate them, placing the infants in little steel chambers with no contact with anything else. He kept them in there for up to a year, causing irreparable psychosis in many of the monkeys.

The monkeys were later returned to a group, but were bullied; others starved themselves to death. When the test subjects later became mothers, they would chew off the fingers of their offspring or crush their heads. Not only were Harlow’s experiments extreme, they revealed nothing new about social interactions.

Luckily, the APA's Code of Conduct brought ethics in psychological experiments. Review boards enforce these ethics to prevent experiments like the ones listed above from occurring.

View the rest of Alltime10s video to see the most disturbing social experiment in the 20th century.

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Three Psychology Experiments That Pushed the Limit of Ethics

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Last month, a team of volunteers emerged from 40 days of isolation in the Lombrives cave in south-west France. This ordeal was part of a scientific study called the Deep Time experiment. The volunteers were tasked with going without sunlight, phones or clocks for the duration of the experiment. The study aimed to understand how the human brain would be affected as it lost its grasp on time and space. Putting human subjects, even volunteers, through this might seem ethically dubious, but pales in comparison to the questions raised by these three studies.

The ultimate isolation: Hebb’s “pathological boredom”

In 2008, the BBC attempted to re-enact Hebb's experiments. Credit: BBC Horizon

Hebb and his team wanted to see how this environment, one that wasn’t entirely devoid of sensory information, but that was incredibly monotonous and boring, would affect the volunteers. Initially, the participants, who were all university students, thought about their results, or the papers they had due. But after a while, their minds instead drifted onto memories from their childhood. Eventually, most of the participants reported that they became unable to think about anything for any length of time. These details were reported by Hebb’s collaborator Woodburn Heron in an article published in Scientific American . The subjects also showed impaired mental performance, registering lower results on tests of mental arithmetic and word association. Most strikingly of all, the subjects reported that, despite their complete absence of sensory stimulation, they experienced an array of hallucinations, including one participant who saw endless images of babies. These hallucinations, which Heron compared to the effects of the hallucinogenic drug mescaline, grew in complexity over time – one participant eventually reported “a procession of squirrels with sacks over their shoulders marching ‘purposefully’across the visual field.” The hallucinations were accompanied by sounds and even sensations across the volunteers’ bodies. Summing up these weird and distressing effects, Heron concluded that “a changing sensory environment seems essential for human beings.”

How malleable is our willpower?

The facebook study: how contagious are emotions.

Credit: Pixabay

This study started huge controversy when it was ascertained that the only consent Facebook sought was signing up for the platform. Facebook's Data Use Policy, the company said, gave them all the permission they needed to play around with users’ feeds. Whilst these findings were interesting, the ethically dubious way in which the study was conducted makes for uncomfortable reading. The ethical quandaries involved, and the reasons why the study was able to bypass certain regulations, were summed up by bioethicist Michelle N. Meyer in an article for WIRED . 

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Some of psychology's most influential studies were also completely unethical

by Susannah Locke

Some of the most important studies in the history of psychology couldn’t be done today — because they were incredibly unethical.

That includes the “Little Albert” study from 1920, in which researchers purposefully terrified a small child to study how fear works. It also includes the famous Stanford prison experiment of 1971, in which subjects acted as prison guards and mistreated fake inmates — a powerful look at how cultural roles can influence behavior. These studies and their findings were hugely influential. They would also — for good reason — be barred from happening today.

Many of these important studies can no longer be replicated

Nowadays, all research being conducted with federal funding has to be reviewed for several ethical criteria. For example, the benefits to society have to outweigh the risks to the participants. And volunteers have to fully consent, understand the risks, and know that they can quit at any time.

These rules also mean that many of those important earlier studies — like the Stanford prison experiment — can’t be replicated exactly. So it’s hard to truly test the methods and conclusions of some of the most foundational studies in psychology. And that means that we’re always going to be debating what, exactly, these studies really mean.

So here’s a look at three of the most important psychology studies that you could never get away with today:

1) The “Little Albert” study

( John Watson, via Wikimedia )

For a study published in 1920, researchers John B. Watson and Rosalie Rayner, of Johns Hopkins University, trained a baby boy they called Albert to irrationally fear a white rat and other objects. They did so by repeatedly putting the rat near the baby while striking a steel bar with a hammer to make a terrible, scary noise.

By the end of the experiment, the baby was also terrified of lots of other objects with similar qualities, including a fur coat and a Santa Claus mask with a white beard. The researchers were planning to re-train Albert to not fear these things, but Albert and his family disappeared.

There are many hypotheses for who Albert was. A thorough investigation published in 2009 in the journal of the American Psychological Association concluded that Albert was most likely a boy named Douglas Merritte, the son of a Johns Hopkins wet nurse who left the job at about the same time Albert left the study. Whether or not Albert suffered any long-term effects from this research is still unclear.

Today, scientists could never get away with repeatedly terrifying a small child like this. But t he Little Albert study is widely regarded as the first significant example of learned reflexive responses — or "conditioning" — in a human. ( Ivan Pavlov had already showed conditioning in dogs, which he had trained to salivate when they heard a sound.) That turned out to be important. Conditioning is at the heart of many types of psychological therapy today, including treatments for some addictions and phobias .

2) The Milgram Shock Experiment 5

Ontario Science Centre Milgram electric box ( Isabelle/Flickr )

In the 1960s and ‘70s, Stanley Milgram produced a series of experiments investigating the nature of obedience. In the most famous one, researchers told participants to administer progressively stronger electric shocks to a person in an adjacent room for each wrong answer he gave on a test. (The participants were told that this was a study about learning methods.)

The “learner” was actually in on the study. At one point, after every shock, he started yelling in pain and demanding that it stop. Still, a researcher encouraged the participant to continue giving shocks.

And they did. 65 percent of participants continued shocking until the voltage simply couldn’t go any higher — so high that the learner had stopped making noise and was presumably incapacitated or dead. In other words, these people were willing to injure or possibly even kill someone else just because a researcher had told them to. And the participants had to learn this about themselves.

This experiment has been exceptionally influential in the field of social psychology. It appeared to show how everyday people could act inhumanely in obedience to an authority figure — such as was demonstrated in the atrocities of World War II.

But this study couldn’t get carried out in its entirety today. Although some degree of deception is common in many studies, the anguish of thinking that you’ve severely hurt or killed someone is just too great to justify. And that means the study will always remain subject to much debate.

In 2009, a study went as far as the learner’s first protest and found similar obedience rates at that point. But we’ll never really know if people today would still go all the way.

The Stanford Prison Experiment

( Shutterstock )

In 1971, psychologists recruited male college students to play prisoners or guards 24 hours a day for two weeks at a mock prison in the basement of a Stanford building. This later became known as The Stanford Prison Experiment .

Even though the roles were randomly assigned, some of the guards became so cruel (including sometimes banning clothing and the right to use the toilet, and using increasingly strenuous exercise as punishment) that the researchers stopped the experiment after just six days. And within those six days, several prisoners freaked out so badly that they had to be let go, and one even went on a hunger strike.

Even more remarkable, many of the "prisoners" stayed even though they were clearly in a lot of distress — possibly because they didn't realize they could leave. Today, psychology researchers are expected to tell participants that they have the right to withdraw at any time. But that didn't happen in this study.

The Stanford Prison Experiment, run by psychologist Philip Zimbardo, is one of the most famous pieces of evidence that cultural roles can have an exceptionally strong influence on people’s behavior. It’s become one of the most talked about studies in all of social psychology. But it’s also been contentious. Other researchers have raised questions about the study’s methodology and conclusions. For example, recent news reports about prison brutality may have led participants to simply give psychologists the drama they thought they wanted. And the exact wording of Zimbardo’s instructions may have egged them on.

To really get a sense of how valid the study was, researchers would ideally want to replicate it in full. But good luck trying to do that. “No behavioral research that puts people in that kind of setting can ever be done again in America,” Zimbardo told Stanford’s alumni magazine in 2011.

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Inside 7 Of The Most Horrific Psychological Experiments Ever Performed

From the little albert experiment that terrorized a helpless infant to the monster study that tried to turn non-stuttering children into stutterers, these are some of the most disturbing psychology experiments ever performed on humans..

Psychology is a relatively new scientific field. While inquiries into the workings of the human mind technically trace back to the ancient Greeks, psychology did not officially become a field of academic and scientific study until the 1800s, with many citing Wilhelm Wundt’s 1873 book, Principles of Physiological Psychology and his subsequent founding of the first psychology lab in 1879 as the modern origin of the field.

Wundt primarily focused on the study of human consciousness, and he applied several experimental methods to move his research forward. The German professor’s work was very much “of the time” and can be viewed as unscientific by today’s standards, but his influence on the field is undeniable.

Over a century after Wundt opened his psychology lab, the field of psychology has grown exponentially, and researchers have gained a far deeper understanding of the human mind and human behavior. However, there have been some serious missteps along the way.

The American Psychological Association (APA) didn’t establish its first Code of Ethics until 1953. Before that, human psychology experiments had far more potential risk. The original guidelines have, of course, been adapted and added to over the past 70 years as well — and for good reason.

Below, you’ll find seven examples of disturbing and highly unethical psychology experiments conducted on human subjects.

Disturbing Psychology Experiments: The Little Albert Experiment (1920)

YouTube Psychologist John Watson wearing a Santa Claus mask and scaring “Little Albert.”

Ivan Pavlov’s experiments into classical conditioning are perhaps the most famous psychology experiments of all time. The Russian psychologist found that he could condition dogs to drool when they heard a dinner bell ring — even if there was no dinner in front of them — by creating an association in their minds between the bell being rung and dinner being served.

About 20 years later, in 1920, Johns Hopkins University researchers John Watson and Rosalie Rayner sought to prove that classical conditioning could work on humans just as effectively as it had on Pavlov’s dogs.

Their tests are now known as the Little Albert Experiment .

Throughout the course of the study, Watson and Rayner presented a nine-month-old baby, whom they called “Little Albert,” with several fluffy animals like a rabbit and a white rat. At first, the infant showed no negative reaction to any of the animals and even tried to pet them.

But then, when he was presented with one of the animals again, the researchers would strike a hammer against a steel pipe. The sudden and loud noise scared the baby, and he would start to cry.

Eventually, Albert came to fear anything that resembled the fluffy animals, including his family’s dogs and a bearded Santa Claus mask. His mother, who realized how traumatized he was, pulled him from the study before Watson and Rayner could attempt to reverse the conditioning.

The study is controversial for several reasons. First, creating a fear response is a form of psychological harm that is prohibited in modern experiments — and it was heavily critiqued at the time, as well. Second, the study only had one subject, which effectively rendered it pointless as studies of this nature need a much larger sample size in order for conclusions to be drawn.

Worst of all, however, is that Albert’s ultimate fate remains unknown to this day, and since his conditioning was never reversed, he quite possibly spent the rest of his life afraid of harmless objects and animals.

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Science News

Lies, damned lies and psychology experiments.

Researchers may deceive themselves when they mislead study participants

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By Bruce Bower

October 22, 2010 at 2:09 pm

BASEL, Switzerland — As dusk settled over this charming city by the Rhine in early October, psychologist Ralph Hertwig sipped scotch in his office with a visiting journalist and bemoaned the toxic — and for some researchers, intoxicating — effects of telling lies to gather data and get published.

Hertwig’s theme: Inauthentic experimenters and the research subjects who follow their lead. His case in point: A study in the May Psychological Science reporting that people who wear discount, mock designer sunglasses feel phony as a result and become more likely to cheat and to judge others as unethical.

With apologies to Jerry Lee Lewis, there was a whole lotta fakin’ going on in this investigation. Half of female participants in one trial completed a bogus questionnaire and were told that their answers reflected a preference for counterfeit products. They were then instructed to take a pair of sunglasses from a box marked “Counterfeit Sunglasses” — which actually contained expensive designer shades — and wear them while walking outside the lab for five minutes and then while working on lab tasks that paid money for correct responses.

Volunteers recorded their responses on a work sheet, after having been promised anonymity by the experimenters. But numbers on work sheets were used to identify each responder so that her actual and self-reported performance could be compared.

And behold—relative to women who hadn’t been misled about favoring faux stuff, tricked participants claimed to have made more correct responses than they actually did. In another experiment, misled women frequently described others as unethical and devious.

Hertwig rubbed his eyes wearily. “It’s just as likely that the experimenters’ own behavior encouraged the dishonest behavior that they observed,” he said.

Participants in the counterfeit condition could have read the situation as one in which normal standards of behavior didn’t apply because the researchers approved of designer knock-offs, Hertwig explained. Each woman saw that the experimenter had somehow acquired fake designer gear and displayed it openly. What’s more, the experimenter claimed special insights into people’s likings for counterfeit products, told volunteers to wear the glasses in public and had them evaluate positive statements about the glasses.

Sociologists’ “broken-windows” theory posits that signs of disorder and petty criminal behavior cause such acts to spread in communities. If that’s the case, Hertwig noted, the counterfeit-sunglasses scientists metaphorically “broke their lab’s window and cried foul when participants sprayed graffiti on the wall.”

And assuming volunteers were debriefed after the experiment, as required by the American Psychological Association’s rules of conduct, one shouldn’t expect them to trust any future researchers’ pledges of anonymity.

Ironically, psychologists’ blindness to these issues could stem from a counterfeit-sunglasses effect. “Deceptive research practices may induce a sense of self-alienation and lack of authenticity among experimenters that interferes with analyzing the signals that the experimental situation conveys to participants,” Hertwig mused.

Some of the most famous psychology experiments of the past 60 years have hinged on trickery, despite longstanding ethical and practical concerns about fooling people in the name of science ( SN: 6/20/98, p. 394 ).

Deceptive psychology’s heyday occurred in the 1960s and 1970s. Literature searches conducted by Hertwig and economist Andreas Ortmann of the University of New South Wales in Sydney, Australia, indicate that experimenters still mislead volunteers in between one-third and one-half of studies published in major social psychology journals.

Hertwig doesn’t want to ban deceptive research practices. He’d settle for researchers taking off their rose-colored, counterfeit sunglasses and scrutinizing how their devious methods may shape volunteers’ responses.

In other words, let the liar beware.

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How the Classics Changed Research Ethics

Some of history’s most controversial psychology studies helped drive extensive protections for human research participants. some say those reforms went too far..

• Behavioral Research
• Institutional Review Board (IRB)

Photo above: In 1971, APS Fellow Philip Zimbardo halted his classic prison simulation at Stanford after volunteer “guards” became abusive to the “prisoners,” famously leading one prisoner into a fit of sobbing. Photo credit:   PrisonExp.org

Nearly 60 years have passed since Stanley Milgram’s infamous “shock box” study sparked an international focus on ethics in psychological research. Countless historians and psychology instructors assert that Milgram’s experiments—along with studies like the Robbers Cave and Stanford prison experiments—could never occur today; ethics gatekeepers would swiftly bar such studies from proceeding, recognizing the potential harms to the participants. 

But the reforms that followed some of the 20th century’s most alarming biomedical and behavioral studies have overreached, many social and behavioral scientists complain. Studies that pose no peril to participants confront the same standards as experimental drug treatments or surgeries, they contend. The institutional review boards (IRBs) charged with protecting research participants fail to understand minimal risk, they say. Researchers complain they waste time addressing IRB concerns that have nothing to do with participant safety. 

Several factors contribute to this conflict, ethicists say. Researchers and IRBs operate in a climate of misunderstanding, confusing regulations, and a systemic lack of ethics training, said APS Fellow Celia Fisher, a Fordham University professor and research ethicist, in an interview with the Observer . 

“In my view, IRBs are trying to do their best and investigators are trying to do their best,” Fisher said. “It’s more that we really have to enhance communication and training on both sides.” 

‘Sins’ from the past  

Modern human-subjects protections date back to the 1947 Nuremberg Code, the response to Nazi medical experiments on concentration-camp internees. Those ethical principles, which no nation or organization has officially accepted as law or official ethics guidelines, emphasized that a study’s benefits should outweigh the risks and that human subjects should be fully informed about the research and participate voluntarily.  

See the 2014 Observer cover story by APS Fellow Carol A. Tavris, “ Teaching Contentious Classics ,” for more about these controversial studies and how to discuss them with students.

But the discovery of U.S.-government-sponsored research abuses, including the Tuskegee syphilis experiment on African American men and radiation experiments on humans, accelerated regulatory initiatives. The abuses investigators uncovered in the 1970s, 80s, and 90s—decades after the experiments had occurred—heightened policymakers’ concerns “about what else might still be going on,” George Mason University historian Zachary M. Schrag explained in an interview. These concerns generated restrictions not only on biomedical research but on social and behavioral studies that pose a minute risk of harm.  

“The sins of researchers from the 1940s led to new regulations in the 1990s, even though it was not at all clear that those kinds of activities were still going on in any way,” said Schrag, who chronicled the rise of IRBs in his book  Ethical Imperialism: Institutional Review Boards and the Social Sciences, 1965–2009.  

Accompanying the medical research scandals were controversial psychological studies that provided fodder for textbooks, historical tomes, and movies.  

• In the early 1950s, social psychologist Muzafer Sherif and his colleagues used a Boy Scout camp called Robbers Cave to study intergroup hostility. They randomly assigned preadolescent boys to one of two groups and concocted a series of competitive activities that quickly sparked conflict. They later set up a situation that compelled the boys to overcome their differences and work together. The study provided insights into prejudice and conflict resolution but generated criticism because the children weren’t told they were part of an experiment. 
• In 1961, Milgram began his studies on obedience to authority by directing participants to administer increasing levels of electric shock to another person (a confederate). To Milgram’s surprise, more than 65% of the participants delivered the full voltage of shock (which unbeknownst to them was fake), even though many were distressed about doing so. Milgram was widely criticized for the manipulation and deception he employed to carry out his experiments. 
• In 1971, APS Fellow Philip Zimbardo halted his classic prison simulation at Stanford after volunteer “guards” became abusive to the “prisoners,” famously leading one prisoner into a fit of sobbing. 

Western policymakers created a variety of safeguards in the wake of these psychological studies and other medical research. Among them was the Declaration of Helsinki, an ethical guide for human-subjects research developed by the Europe-based World Medical Association. The U.S. Congress passed the National Research Act of 1974, which created a commission to oversee participant protections in biomedical and behavioral research. And in the 90s, federal agencies adopted the Federal Policy for the Protection of Human Subjects (better known as the Common Rule), a code of ethics applied to any government-funded research. IRBs review studies through the lens of the Common Rule. After that, social science research, including studies in social psychology, anthropology, sociology, and political science, began facing widespread institutional review (Schrag, 2010).  

Sailing Through Review

Psychological scientists and other researchers who have served on institutional review boards provide these tips to help researchers get their studies reviewed swiftly.  

• Determine whether your study qualifies for minimal-risk exemption from review. Online tools are even in development to help researchers self-determine exempt status (Ben-Shahar, 2019; Schneider & McClutcheon, 2018). 
• If you’re not clear about your exemption, research the regulations to understand how they apply to your planned study. Show you’ve done your homework and have developed a protocol that is safe for your participants.  
• Consult with stakeholders. Look for advocacy groups and representatives from the population you plan to study. Ask them what they regard as fair compensation for participation. Get their feedback about your questionnaires and consent forms to make sure they’re understandable. These steps help you better show your IRB that the population you’re studying will find the protections adequate (Fisher, 2022). 
• Speak to IRB members or staff before submitting the protocol. Ask them their specific concerns about your study, and get guidance on writing up the protocol to address those concerns. Also ask them about expected turnaround times so you can plan your submission in time to meet any deadlines associated with your study (e.g., grant application deadlines).  

Ben-Shahar, O. (2019, December 2). Reforming the IRB in experimental fashion. The Regulatory Review . University of Pennsylvania. https://www.theregreview.org/2019/12/02/ben-shahar-reforming-irb-experimental-fashion/  

Fisher, C. B. (2022). Decoding the ethics code: A practical guide for psychologists (5 th ed.). Sage Publications. 

Schneider, S. L. & McCutcheon, J. A. (2018).  Proof of concept: Use of a wizard for self-determination of IRB exempt status . Federal Demonstration Partnership.   http://thefdp.org/default/assets/File/Documents/wizard_pilot_final_rpt.pdf  

Social scientists have long contended that the Common Rule was largely designed to protect participants in biomedical experiments—where scientists face the risk of inducing physical harm on subjects—but fits poorly with the other disciplines that fall within its reach.

“It’s not like the IRBs are trying to hinder research. It’s just that regulations continue to be written in the medical model without any specificity for social science research,” she explained. 

The Common Rule was updated in 2018 to ease the level of institutional review for low-risk research techniques (e.g., surveys, educational tests, interviews) that are frequent tools in social and behavioral studies. A special committee of the National Research Council (NRC), chaired by APS Past President Susan Fiske, recommended many of those modifications. Fisher was involved in the NRC committee, along with APS Fellows Richard Nisbett (University of Michigan) and Felice J. Levine (American Educational Research Association), and clinical psychologist Melissa Abraham of Harvard University. But the Common Rule reforms have yet to fully expedite much of the research, partly because the review boards remain confused about exempt categories, Fisher said.  

Interference or support?  

That regulatory confusion has generated sour sentiments toward IRBs. For decades, many social and behavioral scientists have complained that IRBs effectively impede scientific progress through arbitrary questions and objections. 

In a Perspectives on Psychological Science  paper they co-authored, APS Fellows Stephen Ceci of Cornell University and Maggie Bruck of Johns Hopkins University discussed an IRB rejection of their plans for a study with 6- to 10-year-old participants. Ceci and Bruck planned to show the children videos depicting a fictional police officer engaging in suggestive questioning of a child.  

“The IRB refused to approve the proposal because it was deemed unethical to show children public servants in a negative light,” they wrote, adding that the IRB held firm on its rejection despite government funders already having approved the study protocol (Ceci & Bruck, 2009).   

Other scientists have complained the IRBs exceed their Common Rule authority by requiring review of studies that are not government funded. In 2011, psychological scientist Jin Li sued Brown University in federal court for barring her from using data she collected in a privately funded study on educational testing. Brown’s IRB objected to the fact that she paid her participants different amounts of compensation based on need. (A year later, the university settled the case with Li.) 

In addition, IRBs often hover over minor aspects of a study that have no genuine relation to participant welfare, Ceci said in an email interview.  

“You can have IRB approval and later decide to make a nominal change to the protocol (a frequent one is to add a new assistant to the project or to increase the sample size),” he wrote. “It can take over a month to get approval. In the meantime, nothing can move forward and the students sit around waiting.” 

Not all researchers view institutional review as a roadblock. Psychological scientist Nathaniel Herr, who runs American University’s Interpersonal Emotion Lab and has served on the school’s IRB, says the board effectively collaborated with researchers to ensure the study designs were safe and that participant privacy was appropriately protected 

“If the IRB that I operated on saw an issue, they shared suggestions we could make to overcome that issue,” Herr said. “It was about making the research go forward. I never saw a project get shut down. It might have required a significant change, but it was often about confidentiality and it’s something that helps everybody feel better about the fact we weren’t abusing our privilege as researchers. I really believe it [the review process] makes the projects better.” 

Some universities—including Fordham University, Yale University, and The University of Chicago—even have social and behavioral research IRBs whose members include experts optimally equipped to judge the safety of a psychological study, Fisher noted. 

Training gaps  

Institutional review is beset by a lack of ethics training in research programs, Fisher believes. While students in professional psychology programs take accreditation-required ethics courses in their doctoral programs, psychologists in other fields have no such requirement. In these programs, ethics training is often limited to an online program that provides, at best, a perfunctory overview of federal regulations. 

“It gives you the fundamental information, but it has nothing to do with our real-world deliberations about protecting participants,” she said. 

Additionally, harm to a participant is difficult to predict. As sociologist Martin Tolich of University of Otago in New Zealand wrote, the Stanford prison study had been IRB-approved. 

“Prediction of harm with any certainty is not necessarily possible, and should not be the aim of ethics review,” he argued. “A more measured goal is the minimization of risk, not its eradication” (Tolich, 2014). 

Fisher notes that scientists aren’t trained to recognize and respond to adverse events when they occur during a study. 

“To be trained in research ethics requires not just knowing you have to obtain informed consent,” she said. “It’s being able to apply ethical reasoning to each unique situation. If you don’t have the training to do that, then of course you’re just following the IRB rules, which are very impersonal and really out of sync with the true nature of what we’re doing.” 

Researchers also raise concerns that, in many cases, the regulatory process harms vulnerable populations rather than safeguards them. Fisher and psychological scientist Brian Mustanski of University of Illinois at Chicago wrote in 2016, for example, that the review panels may be hindering HIV prevention strategies by requiring researchers to get parental consent before including gay and bisexual adolescents in their studies. Under that requirement, youth who are not out to their families get excluded. Boards apply those restrictions even in states permitting minors to get HIV testing and preventive medication without parental permission—and even though federal rules allow IRBs to waive parental consent in research settings (Mustanski & Fisher, 2016) 

IRBs also place counterproductive safety limits on suicide and self-harm research, watching for any sign that a participant might need to be removed from a clinical study and hospitalized. 

“The problem is we know that hospitalization is not the panacea,” Fisher said. “It stops suicidality for the moment, but actually the highest-risk period is 3 months after the first hospitalization for a suicide attempt. Some of the IRBs fail to consider that a non-hospitalization intervention that’s being tested is just as safe as hospitalization. It’s a difficult problem, and I don’t blame them. But if we have to take people out of a study as soon as they reach a certain level of suicidality, then we’ll never find effective treatment.” 

Communication gaps  

Supporters of the institutional review process say researchers tend to approach the IRB process too defensively, overlooking the board’s good intentions.  

“Obtaining clarification or requesting further materials serve to verify that protections are in place,” a team of institutional reviewers wrote in an editorial for  Psi Chi Journal of Psychological Research . “If researchers assume that IRBs are collaborators in the research process, then these requests can be seen as prompts rather than as admonitions” (Domenech Rodriguez et al., 2017). 

Fisher agrees that researchers’ attitudes play a considerable role in the conflicts that arise over ethics review. She recommends researchers develop each protocol with review-board questions in mind (see sidebar). 

“For many researchers, there’s a disdain for IRBs,” she said. “IRBs are trying their hardest. They don’t want to reject research. It’s just that they’re not informed. And sometimes if behavioral scientists or social scientists are disdainful of their IRBs, they’re not communicating with them.” 

Some researchers are building evidence to help IRBs understand the level of risk associated with certain types of psychological studies.  

• In a study involving more than 500 undergraduate students, for example, psychological scientists at the University of New Mexico found that the participants were less upset than expected by questionnaires about sex, trauma , and other sensitive topics. This finding, the researchers reported in  Psychological Science , challenges the usual IRB assumption about the stress that surveys on sex and trauma might inflict on participants (Yeater et al., 2012). 
• A study involving undergraduate women indicated that participants who had experienced child abuse , although more likely than their peers to report distress from recalling the past as part of a study, were also more likely to say that their involvement in the research helped them gain insight into themselves and hoped it would help others (Decker et al., 2011). 
• A multidisciplinary team, including APS Fellow R. Michael Furr of Wake Forest University, found that adolescent psychiatric patients showed a drop in suicide ideation after being questioned regularly about their suicidal thoughts over the course of 2 years. This countered concerns that asking about suicidal ideation would trigger an increase in such thinking (Mathias et al., 2012). 
• A meta-analysis of more than 70 participant samples—totaling nearly 74,000 individuals—indicated that people may experience only moderate distress when discussing past traumas in research studies. They also generally might find their participation to be a positive experience, according to the findings (Jaffe et al., 2015). 

The takeaways  

So, are the historians correct? Would any of these classic experiments survive IRB scrutiny today? 

Reexaminations of those studies make the question arguably moot. Recent revelations about some of these studies suggest that scientific integrity concerns may taint the legacy of those findings as much as their impact on participants did (Le Texier, 2019, Resnick, 2018; Perry, 2018).  

Also, not every aspect of the controversial classics is taboo in today’s regulatory environment. Scientists have won IRB approval to conceptually replicate both the Milgram and Stanford prison experiments (Burger, 2009; Reicher & Haslam, 2006). They simply modified the protocols to avert any potential harm to the participants. (Scholars, including Zimbardo himself, have questioned the robustness of those replication findings [Elms, 2009; Miller, 2009; Zimbardo, 2006].) 

Many scholars believe there are clear and valuable lessons from the classic experiments. Milgram’s work, for instance, can inject clarity into pressing societal issues such as political polarization and police brutality . Ethics training and monitoring simply need to include those lessons learned, they say. 

“We should absolutely be talking about what Milgram did right, what he did wrong,” Schrag said. “We can talk about what we can learn from that experience and how we might answer important questions while respecting the rights of volunteers who participate in psychological experiments.”  

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References   

Burger, J. M. (2009). Replicating Milgram: Would people still obey today? American Psychologist , 64 (1), 1–11. https://doi.org/10.1037/a0010932  

Ceci, S. J. & Bruck, M. (2009). Do IRBs pass the minimal harm test? Perspectives on Psychological Science , 4 (1), 28–29. https://doi.org/10.1111/j.1745-6924.2009.01084.x   

Decker, S. E., Naugle, A. E., Carter-Visscher, R., Bell, K., & Seifer, A. (2011). Ethical issues in research on sensitive topics: Participants’ experiences of stress and benefit . Journal of Empirical Research on Human Research Ethics: An International Journal , 6 (3), 55–64. https://doi.org/10.1525/jer.2011.6.3.55  

Domenech Rodriguez, M. M., Corralejo, S. M., Vouvalis, N., & Mirly, A. K. (2017). Institutional review board: Ally not adversary. Psi Chi Journal of Psychological Research , 22 (2), 76–84.  https://doi.org/10.24839/2325-7342.JN22.2.76  

Elms, A. C. (2009). Obedience lite. American Psychologist , 64 (1), 32–36.  https://doi.org/10.1037/a0014473

Fisher, C. B., True, G., Alexander, L., & Fried, A. L. (2009). Measures of mentoring, department climate, and graduate student preparedness in the responsible conduct of psychological research. Ethics & Behavior , 19 (3), 227–252. https://doi.org/10.1080/10508420902886726  

Jaffe, A. E., DiLillo, D., Hoffman, L., Haikalis, M., & Dykstra, R. E. (2015). Does it hurt to ask? A meta-analysis of participant reactions to trauma research. Clinical Psychology Review , 40 , 40–56. https://doi.org/10.1016/j.cpr.2015.05.004  

Le Texier, T. (2019). Debunking the Stanford Prison experiment. American Psychologist , 74 (7), 823–839. http://dx.doi.org/10.1037/amp0000401  

Mathias, C. W., Furr, R. M., Sheftall, A. H., Hill-Kapturczak, N., Crum, P., & Dougherty, D. M. (2012). What’s the harm in asking about suicide ideation? Suicide and Life-Threatening Behavior , 42 (3), 341–351. https://doi.org/10.1111/j.1943-278X.2012.0095.x  

Miller, A. G. (2009). Reflections on “Replicating Milgram” (Burger, 2009). American Psychologist , 64 (1), 20–27. https://doi.org/10.1037/a0014407  

Mustanski, B., & Fisher, C. B. (2016). HIV rates are increasing in gay/bisexual teens: IRB barriers to research must be resolved to bend the curve.  American Journal of Preventive Medicine ,  51 (2), 249–252. https://doi.org/10.1016/j.amepre.2016.02.026  

Perry, G. (2018). The lost boys: Inside Muzafer Sherif’s Robbers Cave experiment. Scribe Publications.  

Reicher, S. & Haslam, S. A. (2006). Rethinking the psychology of tyranny: The BBC prison study. British Journal of Social Psychology , 45 , 1–40. https://doi.org/10.1348/014466605X48998  

Resnick, B. (2018, June 13). The Stanford prison experiment was massively influential. We just learned it was a fraud. Vox. https://www.vox.com/2018/6/13/17449118/stanford-prison-experiment-fraud-psychology-replication  

Schrag, Z. M. (2010). Ethical imperialism: Institutional review boards and the social sciences, 1965–2009 . Johns Hopkins University Press. 

Tolich, M. (2014). What can Milgram and Zimbardo teach ethics committees and qualitative researchers about minimal harm? Research Ethics , 10 (2), 86–96. https://doi.org/10.1177/1747016114523771  

Yeater, E., Miller, G., Rinehart, J., & Nason, E. (2012). Trauma and sex surveys meet minimal risk standards: Implications for institutional review boards.  Psychological Science , 23 (7), 780–787. https://doi.org/10.1177/0956797611435131  

Zimbardo, P. G. (2006). On rethinking the psychology of tyranny: The BBC prison study. British Journal of Social Psychology , 45 , 47–53. https://doi.org/10.1348/014466605X81720  

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Top 10 Unethical Psychological Experiments

Psychology is a relatively new science which gained popularity in the early 20th century with Wilhelm Wundt. In the zeal to learn about the human thought process and behavior, many early psychiatrists went too far with their experimentations, leading to stringent ethics codes and standards. Though these are highly unethical experiments, it should be mentioned that they did pave the way to induct our current ethical standards of experiments, and that should be seen as a positive. There is some crossover on this list with the Top 10 Evil Human Experiments . Three items from that list are reproduced here (items 8, 9, and 10) for the sake of completeness.

The Monster Study was a stuttering experiment on 22 orphan children in Davenport, Iowa, in 1939 conducted by Wendell Johnson at the University of Iowa. Johnson chose one of his graduate students, Mary Tudor, to conduct the experiment and he supervised her research. After placing the children in control and experimental groups, Tudor gave positive speech therapy to half of the children, praising the fluency of their speech, and negative speech therapy to the other half, belittling the children for every speech imperfection and telling them they were stutterers. Many of the normal speaking orphan children who received negative therapy in the experiment suffered negative psychological effects and some retained speech problems during the course of their life. Dubbed “The Monster Study” by some of Johnson’s peers who were horrified that he would experiment on orphan children to prove a theory, the experiment was kept hidden for fear Johnson’s reputation would be tarnished in the wake of human experiments conducted by the Nazis during World War II. The University of Iowa publicly apologized for the Monster Study in 2001.

South Africa’s apartheid army forced white lesbian and gay soldiers to undergo ‘sex-change’ operations in the 1970’s and the 1980’s, and submitted many to chemical castration, electric shock, and other unethical medical experiments. Although the exact number is not known, former apartheid army surgeons estimate that as many as 900 forced ‘sexual reassignment’ operations may have been performed between 1971 and 1989 at military hospitals, as part of a top-secret program to root out homosexuality from the service.

Army psychiatrists aided by chaplains aggressively ferreted out suspected homosexuals from the armed forces, sending them discretely to military psychiatric units, chiefly ward 22 of 1 Military Hospital at Voortrekkerhoogte, near Pretoria. Those who could not be ‘cured’ with drugs, aversion shock therapy, hormone treatment, and other radical ‘psychiatric’ means were chemically castrated or given sex-change operations.

Although several cases of lesbian soldiers abused have been documented so far—including one botched sex-change operation—most of the victims appear to have been young, 16 to 24-year-old white males drafted into the apartheid army.

Dr. Aubrey Levin (the head of the study) is now Clinical Professor in the Department of Psychiatry (Forensic Division) at the University of Calgary’s Medical School. He is also in private practice, as a member in good standing of the College of Physicians and Surgeons of Alberta.

This study was not necessarily unethical, but the results were disastrous, and its sheer infamy puts it on this list. Famed psychologist Philip Zimbardo led this experiment to examine that behavior of individuals when placed into roles of either prisoner or guard and the norms these individuals were expected to display.

Prisoners were put into a situation purposely meant to cause disorientation, degradation, and depersonalization. Guards were not given any specific directions or training on how to carry out their roles. Though at first, the students were unsure of how to carry out their roles, eventually they had no problem. The second day of the experiment invited a rebellion by the prisoners, which brought a severe response from the guards. Things only went downhill from there.

Guards implemented a privilege system meant to break solidarity between prisoners and create distrust between them. The guards became paranoid about the prisoners, believing they were out to get them. This caused the privilege system to be controlled in every aspect, even in the prisoners’ bodily functions. Prisoners began to experience emotional disturbances, depression, and learned helplessness. During this time, prisoners were visited by a prison chaplain. They identified themselves as numbers rather than their names, and when asked how they planned to leave the prison, prisoners were confused. They had completely assimilated into their roles.

Dr. Zimbardo ended the experiment after five days, when he realized just how real the prison had become to the subjects. Though the experiment lasted only a short time, the results are very telling. How quickly someone can abuse their control when put into the right circumstances. The scandal at Abu Ghraib that shocked the U.S. in 2004 is prime example of Zimbardo’s experiment findings.

While animal experimentation can be incredibly helpful in understanding man, and developing life saving drugs, there have been experiments which go well beyond the realms of ethics. The monkey drug trials of 1969 were one such case. In this experiment, a large group of monkeys and rats were trained to inject themselves with an assortment of drugs, including morphine, alcohol, codeine, cocaine, and amphetamines. Once the animals were capable of self-injecting, they were left to their own devices with a large supply of each drug.

The animals were so disturbed (as one would expect) that some tried so hard to escape that they broke their arms in the process. The monkeys taking cocaine suffered convulsions and in some cases tore off their own fingers (possible as a consequence of hallucinations), one monkey taking amphetamines tore all of the fur from his arm and abdomen, and in the case of cocaine and morphine combined, death would occur within 2 weeks.

The point of the experiment was simply to understand the effects of addiction and drug use; a point which, I think, most rational and ethical people would know did not require such horrendous treatment of animals.

In 1924, Carney Landis, a psychology graduate at the University of Minnesota developed an experiment to determine whether different emotions create facial expressions specific to that emotion. The aim of this experiment was to see if all people have a common expression when feeling disgust, shock, joy, and so on.

Most of the participants in the experiment were students. They were taken to a lab and their faces were painted with black lines, in order to study the movements of their facial muscles. They were then exposed to a variety of stimuli designed to create a strong reaction. As each person reacted, they were photographed by Landis. The subjects were made to smell ammonia, to look at pornography, and to put their hands into a bucket of frogs. But the controversy around this study was the final part of the test.

Participants were shown a live rat and given instructions to behead it. While all the participants were repelled by the idea, fully one third did it. The situation was made worse by the fact that most of the students had no idea how to perform this operation in a humane manner and the animals were forced to experience great suffering. For the one third who refused to perform the decapitation, Landis would pick up the knife and cut the animals head off for them.

The consequences of the study were actually more important for their evidence that people are willing to do almost anything when asked in a situation like this. The study did not prove that humans have a common set of unique facial expressions.

John Watson, father of behaviorism, was a psychologist who was apt to using orphans in his experiments. Watson wanted to test the idea of whether fear was innate or a conditioned response. Little Albert, the nickname given to the nine month old infant that Watson chose from a hospital, was exposed to a white rabbit, a white rat, a monkey, masks with and without hair, cotton wool, burning newspaper, and a miscellanea of other things for two months without any sort of conditioning. Then experiment began by placing Albert on a mattress in the middle of a room. A white laboratory rat was placed near Albert and he was allowed to play with it. At this point, the child showed no fear of the rat.

Then Watson would make a loud sound behind Albert’s back by striking a suspended steel bar with a hammer when the baby touched the rat. In these occasions, Little Albert cried and showed fear as he heard the noise. After this was done several times, Albert became very distressed when the rat was displayed. Albert had associated the white rat with the loud noise and was producing the fearful or emotional response of crying.

Little Albert started to generalize his fear response to anything fluffy or white (or both). The most unfortunate part of this experiment is that Little Albert was not desensitized to his fear. He left the hospital before Watson could do so.

In 1965, psychologists Mark Seligman and Steve Maier conducted an experiment in which three groups of dogs were placed in harnesses. Dogs from group one were released after a certain amount of time, with no harm done. Dogs from group two were paired up and leashed together, and one from each pair was given electrical shocks that could be ended by pressing a lever. Dogs from group three were also paired up and leashed together, one receiving shocks, but the shocks didn’t end when the lever was pressed. Shocks came randomly and seemed inevitable, which caused “learned helplessness,” the dogs assuming that nothing could be done about the shocks. The dogs in group three ended up displaying symptoms of clinical depression.

Later, group three dogs were placed in a box with by themselves. They were again shocked, but they could easily end the shocks by jumping out of the box. These dogs simply “gave up,” again displaying learned helplessness. The image above is a healthy pet dog in a science lab, not an animal used in experimentation.

The notorious Milgrim Study is one of the most well known of psychology experiments. Stanley Milgram, a social psychologist at Yale University, wanted to test obedience to authority. He set up an experiment with “teachers” who were the actual participants, and a “learner,” who was an actor. Both the teacher and the learner were told that the study was about memory and learning.

Both the learner and the teacher received slips that they were told were given to them randomly, when in fact, both had been given slips that read “teacher.” The actor claimed to receive a “learner” slip, so the teacher was deceived. Both were separated into separate rooms and could only hear each other. The teacher read a pair of words, following by four possible answers to the question. If the learner was incorrect with his answer, the teacher was to administer a shock with voltage that increased with every wrong answer. If correct, there would be no shock, and the teacher would advance to the next question.

In reality, no one was being shocked. A tape recorder with pre-recorded screams was hooked up to play each time the teacher administered a shock. When the shocks got to a higher voltage, the actor/learner would bang on the wall and ask the teacher to stop. Eventually all screams and banging would stop and silence would ensue. This was the point when many of the teachers exhibited extreme distress and would ask to stop the experiment. Some questioned the experiment, but many were encouraged to go on and told they would not be responsible for any results.

If at any time the subject indicated his desire to halt the experiment, he was told by the experimenter, Please continue. The experiment requires that you continue. It is absolutely essential that you continue. You have no other choice, you must go on. If after all four orders the teacher still wished to stop the experiment, it was ended. Only 14 out of 40 teachers halted the experiment before administering a 450 volt shock, though every participant questioned the experiment, and no teacher firmly refused to stop the shocks before 300 volts.

In 1981, Tom Peters and Robert H. Waterman Jr. wrote that the Milgram Experiment and the later Stanford prison experiment were frightening in their implications about the danger lurking in human nature’s dark side.

Dr. Harry Harlow was an unsympathetic person, using terms like the “rape rack” and “iron maiden” in his experiments. He is most well-known for the experiments he conducted on rhesus monkeys concerning social isolation. Dr. Harlow took infant rhesus monkeys who had already bonded with their mothers and placed them in a stainless steel vertical chamber device alone with no contact in order to sever those bonds. They were kept in the chambers for up to one year. Many of these monkeys came out of the chamber psychotic, and many did not recover. Dr. Harlow concluded that even a happy, normal childhood was no defense against depression, while science writer Deborah Blum called these, “common sense results.”

Gene Sackett of the University of Washington in Seattle, one of Harlow’s doctoral students, stated he believes the animal liberation movement in the U.S. was born as a result of Harlow’s experiments. William Mason, one of Harlow’s students, said that Harlow “kept this going to the point where it was clear to many people that the work was really violating ordinary sensibilities, that anybody with respect for life or people would find this offensive. It’s as if he sat down and said, ‘I’m only going to be around another ten years. What I’d like to do, then, is leave a great big mess behind.’ If that was his aim, he did a perfect job.”

In 1965, a baby boy was born in Canada named David Reimer. At eight months old, he was brought in for a standard procedure: circumcision. Unfortunately, during the process his penis was burned off. This was due to the physicians using an electrocautery needle instead of a standard scalpel. When the parents visited psychologist John Money, he suggested a simple solution to a very complicated problem: a sex change. His parents were distraught about the situation, but they eventually agreed to the procedure. They didn’t know that the doctor’s true intentions were to prove that nurture, not nature, determined gender identity. For his own selfish gain, he decided to use David as his own private case study.

David, now Brenda, had a constructed vagina and was given hormonal supplements. Dr. Money called the experiment a success, neglecting to report the negative effects of Brenda’s surgery. She acted very much like a stereotypical boy and had conflicting and confusing feelings about an array of topics. Worst of all, her parents did not inform her of the horrific accident as an infant. This caused a devastating tremor through the family. Brenda’s mother was suicidal, her father was alcoholic, and her brother was severely depressed.

Finally, Brenda’s parents gave her the news of her true gender when she was fourteen years old. Brenda decided to become David again, stopped taking estrogen, and had a penis reconstructed. Dr. Money reported no further results beyond insisting that the experiment had been a success, leaving out many details of David’s obvious struggle with gender identity. At the age of 38, David committed suicide.

This article is licensed under the GFDL because it contains quotations from Wikipedia.

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11+ most controversial psychological experiments in history

Here is a glimpse at some of the most controversial, unethical psychological experiments in history..

Kashyap Vyas

Scientific experimentation is a staple of human progress. Academic researchers are usually required to abide by rules and regulations governing the ethics of conducting studies. However, there has always been a very small number of researchers that have moved far beyond what many consider ethical. 

Today, there are strict rules that must be followed when conducting such psychological experiments. For example, the American Psychological Association (APA) has a binding Code of Conduct that must be followed when conducting any kind of experiment. Experimenters are bound to adhere to everything from consent to confidentiality of the experiments.

Moreover, there are review boards and panels that are in charge of reinforcing these strict ethics. Having said that, the norms were not always this stern. That is precisely how some of the following controversial psychological experiments came to be conducted. 

 1.  The Facebook experiment

hocus- focus/iStock

The Facebook Experiment of 2012 created quite an uproar amongst indignant users. Nearly 700,000 Facebook users were subjected to secret psychological tests to gauge the effects of different types of posts.

The details of the experiment came out in a scientific paper published in the Proceedings of the National Academy of Sciences . The paper revealed that, unbeknownst to users, Facebook had tampered with the news feeds of nearly 700,000 people, showing them an abnormally low number of either positive or negative posts. The experiment aimed to determine whether the company could alter the emotional state of its users.

The experiment was designed to determine whether the number of positive or negative comments in a Facebook newsfeed would have any effect on how the user updated their own page. 

News of the research led to outrage from people who felt they had been secretly manipulated by the company.

The researchers revealed that social media users were prone to “emotional contagion” in which they mimicked the type of content of others who posted on their feed. For example, those shown more negative comments posted more negative comments themselves.

Although the results were interesting, Facebook suffered a storm of criticism , with many referring to the social media platform as “terrifying” and “creepy.” The ethics of the experiment have since been debated heavily. 

 2. The O peration Midnight Climax

The US Military and CIA have an extensive history of conducting unusual psychological experiments.

One research project, dubbed Operation Midnight Climax, was conducted in the 1950s under the direction of Allen Dulles, the CIA Director at the time. It was a part of Project MKULTRA, the controversial series of experiments aimed at developing mind control techniques.

This operation was conducted with the motive of exploring the use of “mind-control” drugs and testing the effects of psychoactive drugs like LSD on individuals.

Unknowingly, clients were lured to CIA-run brothels by CIA-paid prostitutes, and psychoactive substances such as LSD were slipped into their drinks. These individuals were then monitored from behind a two-way mirror while they engaged in sexual activities.

The project’s activities expanded over the years to test other agents, such as stink bombs and heroin, on many unsuspecting people. The brothels were also popular with agents, who used them for “quickies.”

The agency shut down MKULTRA in the late 1960s after the CIA’s inspector general’s office  discovered the experiments . However, two related programs, MKSEARCH and Project OFTEN, continued until 1972 and 1973, respectively.

3.  The Aversion Project

The South African Aversion Project was yet another unethical psychology experiment that was conducted on people. Apartheid South Africa was an extremely dangerous place for homosexuals — both black and white. During that time, the government had strict anti-homosexual laws. Being gay was defined as abnormal and homosexuality was considered a mental illness. As a result, aversion therapies and techniques were applied to many South Africans to “cure” them of this illness.

Homosexuals were also often forced to join the military against their will. The Aversion Project mainly consisted of drugging lesbians and gay men, after which they were shown photos of same-sex erotica as they were subjected to electroconvulsive behavior therapy.

Thereafter, they were electrically shocked, and they were shown pictures of the opposite sex erotica. The technique obviously did not work, and the victims were then subjected to hormone therapy.

In some cases, this therapy also included chemical castration. Moreover, more than 900 men and women were forced to undergo a gender reassignment surgery to reorient them, without their consent, of course.

4.  Unnecessary sexual reassignment experiments

One tragic case came about as the result of poor decisions made after a surgical accident, when a seven-month-old Canadian boy was “accidentally castrated” while undergoing a routine circumcision.

After the penis of David Peter Reimer was accidentally maimed, a psychologist convinced his parents that the boy was more likely to successfully reach sexual maturation if he underwent sexual reassignment surgery as a female.

The psychologist, John Money, reported the reassignment was successful and used it as evidence that gender identity is primarily learned. However, as Reimer grew older, he came to realize that he was not a girl and at the age of 15, he transitioned to living as a male. Reimer eventually went public with his story to help discourage similar medical practices and the resulting furor changed medical practices in similar cases. Reimer killed himself at the age of 38, after suffering severe depression.

5.  The Milgram Experiments

A psychologist from Yale University named Stanley Milgram conducted one of the most notorious studies on obedience.

His psychological experiment consisted of analyzing the conflict between personal conscience and obedience to authority. In 1963, Milgram examined justifications that were offered by people accused of performing acts of genocide during World War II .

More often than not, they offered a defense based on the notion of “obedience” and argued that they were merely following their superior’s orders. Therefore, Milgram wanted to examine whether the Germans were somehow naturally obedient, or if there was another reason behind the cruelty.

Based on this experiment, Milgram chose participants through newspaper advertising, urging them to participate in a study at Yale University.

Each participant was then paired with another participant. One was the “learner”, and the other was the “teacher”. In each case, the learner was actually a confederate of Milgram who was pretending to be an actual participant.

The learner was taken to one room and the teacher was taken to the other. The teacher’s room consisted of an electric shock device, along with a row of switches labeled from 15 volts to 450 volts.

The aim of the experiment was to research exactly how far people were willing to go in order to obey an instruction, even if that entailed harming another person. The teacher was instructed to “shock” the student with increasingly high voltages. However, unbeknownst to the teacher, the switches were not real and the learner was faking their reaction. The fake electric shocks gradually increased to levels that would have been fatal had they been real.

The experiment found, unexpectedly, that a very high proportion of subjects would fully obey the instructions, albeit reluctantly.

6. The Stanford Prison Experiment

Eric. E Castro/Wikimedia

The SPE experiment was conducted in 1971 at Stanford University. It was one of the most compelling psychological studies and has become particularly notorious.

In the study, participants were assigned as either guards or inmates in a mock prison at the university. 

The premise of the experiment was that when people are given a certain amount of power over others, they will eventually start to abuse that power. On the flip side, people who are put in a powerless situation will often be driven to submission or even madness.

The experiment found that people who were assigned the role of guards became progressively more cruel and even became willing to inflict psychological torture, while many of the “inmates” passively accepted psychological abuse and actively harassed other prisoners who tried to stop it.

The experiment was abandoned early and has been criticized for using an unscientific methodology, such as instructing the participants on how to behave. Its findings have been called into question, too.

7.  The Monster Study

The Monster Study experiment of 1939 was an admirable experiment on the part of Dr. Wendell Johnson, who was a speech pathologist. He wanted to understand the cause of stuttering. Therefore, he conducted an experiment on a group of children at an orphanage in Davenport Iowa. Johnson did not agree with the prevalent belief that stuttering was an inborn trait that therefore could not be corrected.

As a part of the study, Johnson experimented on 22 orphans and put them into two groups of stutterers and non-stutterers.

Only half of the kids in the stuttering group were actually stutterers. Throughout the experiment, the non-stutterers enjoyed heavy praise, thanks to their conventional speech patterns.

On the other hand, the stuttering group continually received negative reinforcement, and they were always put on edge as a reminder not to stutter. Johnson concluded afterward that the kids who did have stutters in the stuttering group were actually worse off than before and the ones in the stuttering group who hadn’t stuttered before the experiment started stuttering by the end of the experiment.

Johnson established that the problem of stuttering was developmental instead of an innate trait, but he left many children with a lifelong struggle.

 8. The 1969 Monkey Drug Trials

13160449/iStock

The Monkey Drug Trial in 1969 is another one of those psychological experiments that entirely crossed the line.

Despite this trial helping psychologists understand drug addiction better, the three researchers who conducted this experiment at the University of Michigan Medical School completely overstepped their mark, making it another psychological experiment gone wrong.

The researchers hooked Macaque monkeys on illegal substances by injecting the unwitting primates with drugs such as cocaine, morphine, amphetamines, and alcohol.

They did this to see if the monkeys would later actively administer doses of these substances to themselves.

Many monkeys did, and the researchers were able to establish a link between psychological dependence and drug abuse . However, the experiment had questionable scientific value, as the same results might not be reproducible in humans.

In addition to that, despite the establishment of a link, the method was definitely unethical as well as cruel because some of the monkeys died during the experiment.

9. The Robbers Cave Experiment

Cummings Center for the History of Psychology/YouTube

The Robbers Cave Experiment was organized by psychologist Muzafer Sherif in the Robbers Cave State Park, Oklahoma.

Sherif recruited boys of the age group of 11 and 12 for the experiment and split them into two groups. The boys developed an attachment to their groups throughout the first week of the camp by doing various activities together, such as hiking, swimming, etc.

The two groups then spent four days competing with each other in many games. During the competitions, Sherif manipulated the results of the game to bring the game scores exceptionally close. Prejudice between the groups began to become apparent.

Then followed a two-day cooling-off period, where the boys tended to characterize their own group in very favorable terms, and the other group in very unfavorable terms.

Sherif then attempted to reduce the prejudice or inter-group conflict. However, simply increasing the contact of the two groups only made the situation worse, whereas forcing the groups to work together to reach common goals, eased prejudice and tension among the groups.

The experiment confirmed Sherif’s realistic conflict theory (also called realistic group conflict theory) — the idea that group conflict can result from competition over resources.

This experiment is clearly controversial as it uses children as test subjects without their consent or even awareness.

 10. The  Brown-Eyed vs. Blue-Eyed Student Experiments

Jane Elliott was a third-grade teacher who became known for her brown eyes/blue eyes exercise. This experiment went on to demonstrate the impact of racism on education .

The morning after the assassination of Martin Luther King, Elliott told her class that the way in which things were done was going to change. She placed the blue-eyed children at the front of the classroom.

They were given  additional recess time , the pride of place in the front of the classroom, a second helping of food during lunch, and active participation in class discussions.

At the same time, the brown-eyed children had to sit at the back of the class; moreover, they were severely reprimanded for all those things that the blue-eyed kids usually got away with. Elliott even went through all the trouble of making up a scientific fact that supposedly stated blue-eyed people are more intelligent than brown-eyed ones, thanks to the presence of melanin.

The results of the study were stunning. The blue-eyed students performed much better in the assignments whereas those brown-eyed students who usually showed a much better performance in the class were found struggling.

The blue-eyed students also became vicious toward the brown-eyed ones. The next day, Elliott reversed the exercise, and the same results were found. However, the brown-eyed students were not as vicious with their taunts. At the end of the exercise, both groups of children hugged each other and cried. They had learned an essential lesson in racism, even though the process was completely unethical.

 11.  The Little Albert Experiment

John B Watson/Wikimedia

John Watson is a popular psychologist, and people know him as the “Father of Behaviorism.” He was known to use orphans in many of his experiments.

In one of these especially unethical and well-known experiments, Watson employed  Little Albert, a nine-month-old orphan.

In this experiment, Watson exposed Little Albert to many sights and sounds. This included monkeys, rabbits, different masks, and a burning newspaper. In the second part of the experiment, Little Albert was introduced to a white rat.

Much like the earlier things, Little Albert was not scared of the rat. But then, every time Albert touched the rat, Watson made loud noises with a bar made of steel.

This distressed Little Albert as he thought that the noise was coming from the rat. Over time, he showed fear of anything white and/or fluffy. This demonstrated Watson’s hypothesis that it was possible to condition the element of fear in people.

12. Project QKHILLTOP

Mike Mcclaughry

Project QKHILLTOP  was a CIA-developed experiment to study Chinese brainwashing techniques. This shocking psychological experiment was born out of the CIA’s desire to create more effective methods of interrogation. Led by Dr. Harold Wolff of Cornell University Medical School, the controversial experiments explored drugs, imprisonment, deprivation, humiliation, torture, brainwashing, and hypnoses on various subjects. 

13. University of Pennsylvania testing prison inmates 

In 1951, researchers from the University of Pennsylvania began experimenting on inmates at Philadelphia’s Holmesburg Prison. For 20 years, Dr. Albert M. Kligman tested toothpaste, deodorant, shampoo, skin creams, detergents, liquid diets, eye drops, foot powders, and hair dyes on inmates’ skin, to determine if they were safe to use. The tests required constant skin biopsies and painful procedures. 

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History has shown the cruelty of humans towards other human beings and species in their quest to find answers to some questions. In this quest, they forgot about ethics and morals which led to severe repercussions and in some cases, scarred adulthood where children are involved.

However, it is good that people have learned from history and now, researchers need to seek prior permission before conducting experiments with human subjects.

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7 famous psych studies with troubling backstories

By Eleanor Cummins

Posted on Aug 23, 2018 10:30 PM EDT

8 minute read

Psychology 101 textbooks typically include epic tales of the discipline’s history. They chronicle inventive experiments and dazzling results from days of old. But many of the things we think we know about human mind—like the depth of the parent-child bond, or our inclination to submit to authority even when it feels unethical—come from research that’s since been found flimsy, biased, or too unethical to be repeated today. Here are the troublesome backstories to seven classic psychological studies.

Little Albert

In the early 20th century, many American psychologists were under the influence of “behaviorism,” the belief that our behaviors aren’t so much a matter of free will, but of animal-like reflexes and learned responses guided by past experiences. Russian scientist Ivan Pavlov showed that dogs could be taught to salivate at the sound of a bell. But John B. Watson and his colleagues at Johns Hopkins University wanted to show they applied to humans, too.

To do this, they borrowed a 9-month-old baby they called “Albert” and tried to teach him a specific fear. Every time the baby touched a white rat, the researchers made a harsh sound with a hammer, causing him to cry. Eventually, the baby would cry at the sight of the white rat—or a rabbit, or a Santa Claus mask—alone.

At the time the results were published in February 1920, the study was well-regarded and it even appears to have inspired promising new psychologists to enter the field. But harsh criticism of the research, both ethical and practical in nature, has arisen over the intervening century. Albert could not give informed consent to such experimentation, and likely continued to fear certain stimuli long after the study was finished. At the same time, with just one participant and no control group, Watson’s data was effectively meaningless.

The Monster Study

Wendell Johnson was a life-long stutterer. A psychologist and preeminent speech pathologist at the University of Iowa in the 1930s, he set about researching the origins of his own condition. Like the Little Albert experimenters, Johnson harbored a belief that stuttering “begins not in the child’s mouth but in the parent’s ear.” In other words, it had nothing to do with atypical neurological or muscular patterns, it was learned.

Determined to test this hypothesis, Johnson and his collaborator, Mary Tudor, took a dozen children with normal speech patterns from a Davenport, Iowa orphanage and divided them into two groups. Kids in one group were told they had stutters. Kids in the other group weren’t. Tudor’s experiment had mixed results: two children improved their elocution, two didn’t change, and two lost fluency.

Sixty years later, as the New York Times reported , the orphans—now grown up—sued the state and the university, “citing among other things the infliction of emotional distress and fraudulent misrepresentation.” Needless to say, “the monster study,” as it quickly came to be known, could not be repeated today given its long-term consequences for young participants.

Project MKUltra

From 1953 to 1973, the CIA funded covert research on mind control at dozens of reputable institutions, including universities and hospitals. A source of inspiration to horror-fueled shows like Stranger Things and films like Conspiracy Theory, the covert project is today recognized as torture. In the hopes of revealing strategies by which the government could deprogram and reprogram spies or prisoners of wars, unwitting civilians were drugged, hypnotized, submitted to electroshock therapy, and shut away, sometimes for months, in sensory deprivation tanks and isolation chambers.

One of the proponents and practitioners of this research was psychiatrist Donald Ewen Cameron of McGill University’s Allan Memorial Institute. There, patients who entered with everyday conditions like mild anxiety would be submitted to the full bevy of “psychic driving” techniques, which left many of them amnesic, incontinent, child-like in their dependence, and deeply traumatized. His work led to dozens of lawsuits, new legislation, and large settlements to the victims. But at the time he was widely regarded, heading up the American, Canadian, and World psychiatric associations, and even participating in the Nuremberg doctors’ trial that censured experimentation and mass murder by Nazi physicians.

Of course, Cameron’s practices would never pass muster with an ethics review board today… but they probably wouldn’t have passed then, either.

Robbers Cave

The same year Lord of the Flies was published (1954), married psychologists Muzafer and Carolyn Wood Sherif took a group of 22 boys into the woods of Robbers Cave State Park in Oklahoma for a better look at realistic conflict theory.

Over the course of three weeks, the researchers planned to divide the children into two groups; ask them to compete at camp games with the secret hope of creating negativity between the groups; and then force them to come together and cooperate in a crisis. Along the way, the researchers manipulated the circumstances , encouraging the boys to fight and supplying them with tools to fuel their infighting.

The research made Muzafer Sherif a hero in his field, and the study remains important to conflict theorists. But a closer inspection suggests the results are unreliable (though not meaningless). Worse, the whole thing was unethical: Neither the boys nor, it seems, their parents, were informed about the true nature of the summer camp, according to Gina Perry, author of the new book The Lost Boys , which documents Sherif’s work.

Harlow’s monkeys

In the 1950s, University of Wisconsin psychologist Harry Harlow constructed a series of experiments to study the impact of isolation , separation, and neglect on children. To his credit, he didn’t use human babies (as some of his predecessors might have), but the effect on his long-established rhesus macaque colony is historically harrowing.

While his studies spanned decades and took many forms, his most famous experiment forced baby monkeys to choose between two fake surrogates. The “iron maiden” was made only of wire, but had bottles full of milk protruding from its metal chest. The other was covered in a soft cloth, but entirely devoid of food.

If Harlow’s behaviorist theories were right—that parents were there to provide resources, not comfort—the babies should have chosen the surrogate who offered them food over the surrogate who offered them nothing but comfort. But that theory quickly crumbled. The monkeys spent most of their time clinging to the cloth mother, crying out in pain. They visited the iron maiden only when they were too hungry to avoid her metallic frame any longer.

Harlow’s monkey studies were considered foundational to the field of parent-child research, but many contemporary psychologists argue such experiments should never be repeated—on humans or animals.

Milgram experiment

In the 1960s, Yale University psychologist Stanley Milgram devised a way to test the most pressing existential question of the era: Could obedience to authority be enough to persuade ostensibly good people to commit acts generally considered evil?

In the lab, Milgram assigned research participants the role of teacher, then asked them to administer ever-increasing electric shocks to their “student.” As the shocks escalated, the student—secretly a member of the research team and safe from any real harm—cried, yelled, and begged to be freed. Some of the “teachers” refused to continue. But roughly 65 percent administered the most intense voltage anyway.

Controversial since its conception, “the procedure created extreme levels of nervous tension,” Milgram wrote in his original 1963 study. “Profuse sweating, trembling, and stuttering were typical expressions of this emotional disturbance. One unexpected sign of tension—yet to be explained—was the regular occurrence of nervous laughter.” Whether they quit early, or made it to the finish line, participants were riled.

Despite the distress such studies clearly generate, the shock experiment continues to be replicated today, often with similar results. And new research is using Milgram-like methods to study human-robot relationships .

Stanford prison experiment

In 1971, Stanford psychology professor Philip Zimbardo put a group of college students in a fake makeshift jail, randomly assigned them to be guards or prisoners, and watched what unfolded. It appears many of the guards began to act in stereotypically authoritarian ways, though only after some poking and prodding from Zimbardo, the self-appointed prison superintendent. The prisoners, meanwhile, reportedly accepted much of this abuse, though some quit the experiments. Ultimately, the situation escalated to the point that Zimbardo abandoned the project after just six days.

The experiment remains legendary—the stuff of films, documentaries, and textbooks. But scrutiny of Zimbardo’s methodologies, conclusions, and ethics have grown to the point many professors now omit the experiment from their curriculum. “From the beginning, I have always said it’s a demonstration. The only thing that makes it an experiment is the random assignment to prisoners and guards, that’s the independent variable. There is no control group. There’s no comparison group. So it doesn’t fit the standards of what it means to be ‘an experiment,'” Zimbardo said in defense of his work . “It’s a very powerful demonstration of a psychological phenomenon, and it has had relevance.”

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Ethical Principles of Psychologists and Code of Conduct

Effective date June 1, 2003 with amendments effective June 1, 2010 and January 1, 2017. Copyright © 2017 American Psychological Association. All rights reserved.

The American Psychological Association's (APA) Ethical Principles of Psychologists and Code of Conduct (hereinafter referred to as the Ethics Code) consists of an Introduction, a Preamble , five General Principles  (A-E) and specific Ethical Standards . The Introduction discusses the intent, organization, procedural considerations, and scope of application of the Ethics Code. The Preamble and General Principles are aspirational goals to guide psychologists toward the highest ideals of psychology. Although the Preamble and General Principles are not themselves enforceable rules, they should be considered by psychologists in arriving at an ethical course of action. The Ethical Standards set forth enforceable rules for conduct as psychologists. Most of the Ethical Standards are written broadly, in order to apply to psychologists in varied roles, although the application of an Ethical Standard may vary depending on the context. The Ethical Standards are not exhaustive. The fact that a given conduct is not specifically addressed by an Ethical Standard does not mean that it is necessarily either ethical or unethical.

This Ethics Code applies only to psychologists' activities that are part of their scientific, educational, or professional roles as psychologists. Areas covered include but are not limited to the clinical, counseling, and school practice of psychology; research; teaching; supervision of trainees; public service; policy development; social intervention; development of assessment instruments; conducting assessments; educational counseling; organizational consulting; forensic activities; program design and evaluation; and administration. This Ethics Code applies to these activities across a variety of contexts, such as in person, postal, telephone, Internet, and other electronic transmissions. These activities shall be distinguished from the purely private conduct of psychologists, which is not within the purview of the Ethics Code.

Membership in the APA commits members and student affiliates to comply with the standards of the APA Ethics Code and to the rules and procedures used to enforce them. Lack of awareness or misunderstanding of an Ethical Standard is not itself a defense to a charge of unethical conduct.

The procedures for filing, investigating, and resolving complaints of unethical conduct are described in the current Rules and Procedures of the APA Ethics Committee . APA may impose sanctions on its members for violations of the standards of the Ethics Code, including termination of APA membership, and may notify other bodies and individuals of its actions. Actions that violate the standards of the Ethics Code may also lead to the imposition of sanctions on psychologists or students whether or not they are APA members by bodies other than APA, including state psychological associations, other professional groups, psychology boards, other state or federal agencies, and payors for health services. In addition, APA may take action against a member after his or her conviction of a felony, expulsion or suspension from an affiliated state psychological association, or suspension or loss of licensure. When the sanction to be imposed by APA is less than expulsion, the 2001 Rules and Procedures do not guarantee an opportunity for an in-person hearing, but generally provide that complaints will be resolved only on the basis of a submitted record.

The Ethics Code is intended to provide guidance for psychologists and standards of professional conduct that can be applied by the APA and by other bodies that choose to adopt them. The Ethics Code is not intended to be a basis of civil liability. Whether a psychologist has violated the Ethics Code standards does not by itself determine whether the psychologist is legally liable in a court action, whether a contract is enforceable, or whether other legal consequences occur.

The modifiers used in some of the standards of this Ethics Code (e.g., reasonably, appropriate, potentially) are included in the standards when they would (1) allow professional judgment on the part of psychologists, (2) eliminate injustice or inequality that would occur without the modifier, (3) ensure applicability across the broad range of activities conducted by psychologists, or (4) guard against a set of rigid rules that might be quickly outdated. As used in this Ethics Code, the term reasonable means the prevailing professional judgment of psychologists engaged in similar activities in similar circumstances, given the knowledge the psychologist had or should have had at the time.

In the process of making decisions regarding their professional behavior, psychologists must consider this Ethics Code in addition to applicable laws and psychology board regulations. In applying the Ethics Code to their professional work, psychologists may consider other materials and guidelines that have been adopted or endorsed by scientific and professional psychological organizations and the dictates of their own conscience, as well as consult with others within the field. If this Ethics Code establishes a higher standard of conduct than is required by law, psychologists must meet the higher ethical standard. If psychologists' ethical responsibilities conflict with law, regulations, or other governing legal authority, psychologists make known their commitment to this Ethics Code and take steps to resolve the conflict in a responsible manner in keeping with basic principles of human rights.

Psychologists are committed to increasing scientific and professional knowledge of behavior and people's understanding of themselves and others and to the use of such knowledge to improve the condition of individuals, organizations, and society. Psychologists respect and protect civil and human rights and the central importance of freedom of inquiry and expression in research, teaching, and publication. They strive to help the public in developing informed judgments and choices concerning human behavior. In doing so, they perform many roles, such as researcher, educator, diagnostician, therapist, supervisor, consultant, administrator, social interventionist, and expert witness. This Ethics Code provides a common set of principles and standards upon which psychologists build their professional and scientific work.

This Ethics Code is intended to provide specific standards to cover most situations encountered by psychologists. It has as its goals the welfare and protection of the individuals and groups with whom psychologists work and the education of members, students, and the public regarding ethical standards of the discipline.

The development of a dynamic set of ethical standards for psychologists' work-related conduct requires a personal commitment and lifelong effort to act ethically; to encourage ethical behavior by students, supervisees, employees, and colleagues; and to consult with others concerning ethical problems.

This section consists of General Principles. General Principles, as opposed to Ethical Standards, are aspirational in nature. Their intent is to guide and inspire psychologists toward the very highest ethical ideals of the profession. General Principles, in contrast to Ethical Standards, do not represent obligations and should not form the basis for imposing sanctions. Relying upon General Principles for either of these reasons distorts both their meaning and purpose.

Principle A: Beneficence and Nonmaleficence Psychologists strive to benefit those with whom they work and take care to do no harm. In their professional actions, psychologists seek to safeguard the welfare and rights of those with whom they interact professionally and other affected persons, and the welfare of animal subjects of research. When conflicts occur among psychologists' obligations or concerns, they attempt to resolve these conflicts in a responsible fashion that avoids or minimizes harm. Because psychologists' scientific and professional judgments and actions may affect the lives of others, they are alert to and guard against personal, financial, social, organizational, or political factors that might lead to misuse of their influence. Psychologists strive to be aware of the possible effect of their own physical and mental health on their ability to help those with whom they work.

Principle B: Fidelity and Responsibility Psychologists establish relationships of trust with those with whom they work. They are aware of their professional and scientific responsibilities to society and to the specific communities in which they work. Psychologists uphold professional standards of conduct, clarify their professional roles and obligations, accept appropriate responsibility for their behavior, and seek to manage conflicts of interest that could lead to exploitation or harm. Psychologists consult with, refer to, or cooperate with other professionals and institutions to the extent needed to serve the best interests of those with whom they work. They are concerned about the ethical compliance of their colleagues' scientific and professional conduct. Psychologists strive to contribute a portion of their professional time for little or no compensation or personal advantage.

Principle C: Integrity Psychologists seek to promote accuracy, honesty, and truthfulness in the science, teaching, and practice of psychology. In these activities psychologists do not steal, cheat or engage in fraud, subterfuge, or intentional misrepresentation of fact. Psychologists strive to keep their promises and to avoid unwise or unclear commitments. In situations in which deception may be ethically justifiable to maximize benefits and minimize harm, psychologists have a serious obligation to consider the need for, the possible consequences of, and their responsibility to correct any resulting mistrust or other harmful effects that arise from the use of such techniques.

Principle D: Justice Psychologists recognize that fairness and justice entitle all persons to access to and benefit from the contributions of psychology and to equal quality in the processes, procedures, and services being conducted by psychologists. Psychologists exercise reasonable judgment and take precautions to ensure that their potential biases, the boundaries of their competence, and the limitations of their expertise do not lead to or condone unjust practices.

Principle E: Respect for People's Rights and Dignity Psychologists respect the dignity and worth of all people, and the rights of individuals to privacy, confidentiality, and self-determination. Psychologists are aware that special safeguards may be necessary to protect the rights and welfare of persons or communities whose vulnerabilities impair autonomous decision making. Psychologists are aware of and respect cultural, individual, and role differences, including those based on age, gender, gender identity, race, ethnicity, culture, national origin, religion, sexual orientation, disability, language, and socioeconomic status, and consider these factors when working with members of such groups. Psychologists try to eliminate the effect on their work of biases based on those factors, and they do not knowingly participate in or condone activities of others based upon such prejudices.

1.01 Misuse of Psychologists' Work If psychologists learn of misuse or misrepresentation of their work, they take reasonable steps to correct or minimize the misuse or misrepresentation.

1.02 Conflicts Between Ethics and Law, Regulations, or Other Governing Legal Authority If psychologists’ ethical responsibilities conflict with law, regulations, or other governing legal authority, psychologists clarify the nature of the conflict, make known their commitment to the Ethics Code, and take reasonable steps to resolve the conflict consistent with the General Principles and Ethical Standards of the Ethics Code. Under no circumstances may this standard be used to justify or defend violating human rights.

1.03 Conflicts Between Ethics and Organizational Demands   If the demands of an organization with which psychologists are affiliated or for whom they are working are in conflict with this Ethics Code, psychologists clarify the nature of the conflict, make known their commitment to the Ethics Code, and take reasonable steps to resolve the conflict consistent with the General Principles and Ethical Standards of the Ethics Code. Under no circumstances may this standard be used to justify or defend violating human rights.

1.04 Informal Resolution of Ethical Violations When psychologists believe that there may have been an ethical violation by another psychologist, they attempt to resolve the issue by bringing it to the attention of that individual, if an informal resolution appears appropriate and the intervention does not violate any confidentiality rights that may be involved. (See also Standards 1.02, Conflicts Between Ethics and Law, Regulations, or Other Governing Legal Authority , and 1.03, Conflicts Between Ethics and Organizational Demands .)

1.05 Reporting Ethical Violations If an apparent ethical violation has substantially harmed or is likely to substantially harm a person or organization and is not appropriate for informal resolution under Standard 1.04, Informal Resolution of Ethical Violations , or is not resolved properly in that fashion, psychologists take further action appropriate to the situation. Such action might include referral to state or national committees on professional ethics, to state licensing boards, or to the appropriate institutional authorities. This standard does not apply when an intervention would violate confidentiality rights or when psychologists have been retained to review the work of another psychologist whose professional conduct is in question. (See also Standard 1.02, Conflicts Between Ethics and Law, Regulations, or Other Governing Legal Authority .)

1.06 Cooperating with Ethics Committees Psychologists cooperate in ethics investigations, proceedings, and resulting requirements of the APA or any affiliated state psychological association to which they belong. In doing so, they address any confidentiality issues. Failure to cooperate is itself an ethics violation. However, making a request for deferment of adjudication of an ethics complaint pending the outcome of litigation does not alone constitute noncooperation.

1.07 Improper Complaints Psychologists do not file or encourage the filing of ethics complaints that are made with reckless disregard for or willful ignorance of facts that would disprove the allegation.

1.08 Unfair Discrimination Against Complainants and Respondents Psychologists do not deny persons employment, advancement, admissions to academic or other programs, tenure, or promotion, based solely upon their having made or their being the subject of an ethics complaint. This does not preclude taking action based upon the outcome of such proceedings or considering other appropriate information.

2.01 Boundaries of Competence (a) Psychologists provide services, teach, and conduct research with populations and in areas only within the boundaries of their competence, based on their education, training, supervised experience, consultation, study, or professional experience.

(b) Where scientific or professional knowledge in the discipline of psychology establishes that an understanding of factors associated with age, gender, gender identity, race, ethnicity, culture, national origin, religion, sexual orientation, disability, language, or socioeconomic status is essential for effective implementation of their services or research, psychologists have or obtain the training, experience, consultation, or supervision necessary to ensure the competence of their services, or they make appropriate referrals, except as provided in Standard 2.02, Providing Services in Emergencies .

(c) Psychologists planning to provide services, teach, or conduct research involving populations, areas, techniques, or technologies new to them undertake relevant education, training, supervised experience, consultation, or study.

(d) When psychologists are asked to provide services to individuals for whom appropriate mental health services are not available and for which psychologists have not obtained the competence necessary, psychologists with closely related prior training or experience may provide such services in order to ensure that services are not denied if they make a reasonable effort to obtain the competence required by using relevant research, training, consultation, or study.

(e) In those emerging areas in which generally recognized standards for preparatory training do not yet exist, psychologists nevertheless take reasonable steps to ensure the competence of their work and to protect clients/patients, students, supervisees, research participants, organizational clients, and others from harm.

(f) When assuming forensic roles, psychologists are or become reasonably familiar with the judicial or administrative rules governing their roles.

2.02 Providing Services in Emergencies In emergencies, when psychologists provide services to individuals for whom other mental health services are not available and for which psychologists have not obtained the necessary training, psychologists may provide such services in order to ensure that services are not denied. The services are discontinued as soon as the emergency has ended or appropriate services are available.

2.03 Maintaining Competence Psychologists undertake ongoing efforts to develop and maintain their competence.

2.04 Bases for Scientific and Professional Judgments Psychologists' work is based upon established scientific and professional knowledge of the discipline. (See also Standards 2.01e, Boundaries of Competence , and 10.01b, Informed Consent to Therapy .)

2.05 Delegation of Work to Others Psychologists who delegate work to employees, supervisees, or research or teaching assistants or who use the services of others, such as interpreters, take reasonable steps to (1) avoid delegating such work to persons who have a multiple relationship with those being served that would likely lead to exploitation or loss of objectivity; (2) authorize only those responsibilities that such persons can be expected to perform competently on the basis of their education, training, or experience, either independently or with the level of supervision being provided; and (3) see that such persons perform these services competently. (See also Standards 2.02, Providing Services in Emergencies ; 3.05, Multiple Relationships ; 4.01, Maintaining Confidentiality ; 9.01, Bases for Assessments ; 9.02, Use of Assessments ; 9.03, Informed Consent in Assessments ; and 9.07, Assessment by Unqualified Persons .)

2.06 Personal Problems and Conflicts (a) Psychologists refrain from initiating an activity when they know or should know that there is a substantial likelihood that their personal problems will prevent them from performing their work-related activities in a competent manner.

(b) When psychologists become aware of personal problems that may interfere with their performing work-related duties adequately, they take appropriate measures, such as obtaining professional consultation or assistance, and determine whether they should limit, suspend, or terminate their work-related duties. (See also Standard 10.10, Terminating Therapy .)

3.01 Unfair Discrimination In their work-related activities, psychologists do not engage in unfair discrimination based on age, gender, gender identity, race, ethnicity, culture, national origin, religion, sexual orientation, disability, socioeconomic status, or any basis proscribed by law.

3.02 Sexual Harassment Psychologists do not engage in sexual harassment. Sexual harassment is sexual solicitation, physical advances, or verbal or nonverbal conduct that is sexual in nature, that occurs in connection with the psychologist's activities or roles as a psychologist, and that either (1) is unwelcome, is offensive, or creates a hostile workplace or educational environment, and the psychologist knows or is told this or (2) is sufficiently severe or intense to be abusive to a reasonable person in the context. Sexual harassment can consist of a single intense or severe act or of multiple persistent or pervasive acts. (See also Standard 1.08, Unfair Discrimination Against Complainants and Respondents .)

3.03 Other Harassment Psychologists do not knowingly engage in behavior that is harassing or demeaning to persons with whom they interact in their work based on factors such as those persons' age, gender, gender identity, race, ethnicity, culture, national origin, religion, sexual orientation, disability, language, or socioeconomic status.

3.04 Avoiding Harm (a) Psychologists take reasonable steps to avoid harming their clients/patients, students, supervisees, research participants, organizational clients, and others with whom they work, and to minimize harm where it is foreseeable and unavoidable. 

(b) Psychologists do not participate in, facilitate, assist, or otherwise engage in torture, defined as any act by which severe pain or suffering, whether physical or mental, is intentionally inflicted on a person, or in any other cruel, inhuman, or degrading behavior that violates 3.04(a).

3.05 Multiple Relationships 

(a) A multiple relationship occurs when a psychologist is in a professional role with a person and (1) at the same time is in another role with the same person, (2) at the same time is in a relationship with a person closely associated with or related to the person with whom the psychologist has the professional relationship, or (3) promises to enter into another relationship in the future with the person or a person closely associated with or related to the person.

A psychologist refrains from entering into a multiple relationship if the multiple relationship could reasonably be expected to impair the psychologist's objectivity, competence, or effectiveness in performing his or her functions as a psychologist, or otherwise risks exploitation or harm to the person with whom the professional relationship exists.

Multiple relationships that would not reasonably be expected to cause impairment or risk exploitation or harm are not unethical.

(b) If a psychologist finds that, due to unforeseen factors, a potentially harmful multiple relationship has arisen, the psychologist takes reasonable steps to resolve it with due regard for the best interests of the affected person and maximal compliance with the Ethics Code.

(c) When psychologists are required by law, institutional policy, or extraordinary circumstances to serve in more than one role in judicial or administrative proceedings, at the outset they clarify role expectations and the extent of confidentiality and thereafter as changes occur. (See also Standards 3.04, Avoiding Harm , and 3.07, Third-Party Requests for Services .)

3.06 Conflict of Interest Psychologists refrain from taking on a professional role when personal, scientific, professional, legal, financial, or other interests or relationships could reasonably be expected to (1) impair their objectivity, competence, or effectiveness in performing their functions as psychologists or (2) expose the person or organization with whom the professional relationship exists to harm or exploitation.

3.07 Third-Party Requests for Services When psychologists agree to provide services to a person or entity at the request of a third party, psychologists attempt to clarify at the outset of the service the nature of the relationship with all individuals or organizations involved. This clarification includes the role of the psychologist (e.g., therapist, consultant, diagnostician, or expert witness), an identification of who is the client, the probable uses of the services provided or the information obtained, and the fact that there may be limits to confidentiality. (See also Standards 3.05, Multiple relationships , and 4.02, Discussing the Limits of Confidentiality.)

3.08 Exploitative Relationships Psychologists do not exploit persons over whom they have supervisory, evaluative or other authority such as clients/patients, students, supervisees, research participants, and employees. (See also Standards 3.05, Multiple Relationships ; 6.04, Fees and Financial Arrangements ; 6.05, Barter with Clients/Patients ; 7.07, Sexual Relationships with Students and Supervisees ; 10.05, Sexual Intimacies with Current Therapy Clients/Patients ; 10.06, Sexual Intimacies with Relatives or Significant Others of Current Therapy Clients/Patients ; 10.07, Therapy with Former Sexual Partners ; and 10.08, Sexual Intimacies with Former Therapy Clients/Patients .)

3.09 Cooperation with Other Professionals When indicated and professionally appropriate, psychologists cooperate with other professionals in order to serve their clients/patients effectively and appropriately. (See also Standard 4.05, Disclosures .)

3.10 Informed Consent (a) When psychologists conduct research or provide assessment, therapy, counseling, or consulting services in person or via electronic transmission or other forms of communication, they obtain the informed consent of the individual or individuals using language that is reasonably understandable to that person or persons except when conducting such activities without consent is mandated by law or governmental regulation or as otherwise provided in this Ethics Code. (See also Standards 8.02, Informed Consent to Research ; 9.03, Informed Consent in Assessments ; and 10.01, Informed Consent to Therapy .)

(b) For persons who are legally incapable of giving informed consent, psychologists nevertheless (1) provide an appropriate explanation, (2) seek the individual's assent, (3) consider such persons' preferences and best interests, and (4) obtain appropriate permission from a legally authorized person, if such substitute consent is permitted or required by law. When consent by a legally authorized person is not permitted or required by law, psychologists take reasonable steps to protect the individual's rights and welfare.

(c) When psychological services are court ordered or otherwise mandated, psychologists inform the individual of the nature of the anticipated services, including whether the services are court ordered or mandated and any limits of confidentiality, before proceeding.

(d) Psychologists appropriately document written or oral consent, permission, and assent. (See also Standards 8.02, Informed Consent to Research ; 9.03, Informed Consent in Assessments ; and 10.01, Informed Consent to Therapy .)

3.11 Psychological Services Delivered to or Through Organizations (a) Psychologists delivering services to or through organizations provide information beforehand to clients and when appropriate those directly affected by the services about (1) the nature and objectives of the services, (2) the intended recipients, (3) which of the individuals are clients, (4) the relationship the psychologist will have with each person and the organization, (5) the probable uses of services provided and information obtained, (6) who will have access to the information, and (7) limits of confidentiality. As soon as feasible, they provide information about the results and conclusions of such services to appropriate persons.

(b) If psychologists will be precluded by law or by organizational roles from providing such information to particular individuals or groups, they so inform those individuals or groups at the outset of the service.

3.12 Interruption of Psychological Services Unless otherwise covered by contract, psychologists make reasonable efforts to plan for facilitating services in the event that psychological services are interrupted by factors such as the psychologist's illness, death, unavailability, relocation, or retirement or by the client's/patient's relocation or financial limitations. (See also Standard 6.02c, Maintenance, Dissemination, and Disposal of Confidential Records of Professional and Scientific Work .)

4.01 Maintaining Confidentiality Psychologists have a primary obligation and take reasonable precautions to protect confidential information obtained through or stored in any medium, recognizing that the extent and limits of confidentiality may be regulated by law or established by institutional rules or professional or scientific relationship. (See also Standard 2.05, Delegation of Work to Others .)

4.02 Discussing the Limits of Confidentiality (a) Psychologists discuss with persons (including, to the extent feasible, persons who are legally incapable of giving informed consent and their legal representatives) and organizations with whom they establish a scientific or professional relationship (1) the relevant limits of confidentiality and (2) the foreseeable uses of the information generated through their psychological activities. (See also Standard 3.10, Informed Consent .)

(b) Unless it is not feasible or is contraindicated, the discussion of confidentiality occurs at the outset of the relationship and thereafter as new circumstances may warrant.

(c) Psychologists who offer services, products, or information via electronic transmission inform clients/patients of the risks to privacy and limits of confidentiality.

4.03 Recording Before recording the voices or images of individuals to whom they provide services, psychologists obtain permission from all such persons or their legal representatives. (See also Standards 8.03, Informed Consent for Recording Voices and Images in Research ; 8.05, Dispensing with Informed Consent for Research ; and 8.07, Deception in Research .)

4.04 Minimizing Intrusions on Privacy (a) Psychologists include in written and oral reports and consultations, only information germane to the purpose for which the communication is made.

(b) Psychologists discuss confidential information obtained in their work only for appropriate scientific or professional purposes and only with persons clearly concerned with such matters.

4.05 Disclosures (a) Psychologists may disclose confidential information with the appropriate consent of the organizational client, the individual client/patient, or another legally authorized person on behalf of the client/patient unless prohibited by law.

(b) Psychologists disclose confidential information without the consent of the individual only as mandated by law, or where permitted by law for a valid purpose such as to (1) provide needed professional services; (2) obtain appropriate professional consultations; (3) protect the client/patient, psychologist, or others from harm; or (4) obtain payment for services from a client/patient, in which instance disclosure is limited to the minimum that is necessary to achieve the purpose. (See also Standard 6.04e, Fees and Financial Arrangements .)

4.06 Consultations When consulting with colleagues, (1) psychologists do not disclose confidential information that reasonably could lead to the identification of a client/patient, research participant, or other person or organization with whom they have a confidential relationship unless they have obtained the prior consent of the person or organization or the disclosure cannot be avoided, and (2) they disclose information only to the extent necessary to achieve the purposes of the consultation. (See also Standard 4.01, Maintaining Confidentiality .)

4.07 Use of Confidential Information for Didactic or Other Purposes Psychologists do not disclose in their writings, lectures, or other public media, confidential, personally identifiable information concerning their clients/patients, students, research participants, organizational clients, or other recipients of their services that they obtained during the course of their work, unless (1) they take reasonable steps to disguise the person or organization, (2) the person or organization has consented in writing, or (3) there is legal authorization for doing so.

5.01 Avoidance of False or Deceptive Statements (a) Public statements include but are not limited to paid or unpaid advertising, product endorsements, grant applications, licensing applications, other credentialing applications, brochures, printed matter, directory listings, personal resumes or curricula vitae, or comments for use in media such as print or electronic transmission, statements in legal proceedings, lectures and public oral presentations, and published materials. Psychologists do not knowingly make public statements that are false, deceptive, or fraudulent concerning their research, practice, or other work activities or those of persons or organizations with which they are affiliated.

(b) Psychologists do not make false, deceptive, or fraudulent statements concerning (1) their training, experience, or competence; (2) their academic degrees; (3) their credentials; (4) their institutional or association affiliations; (5) their services; (6) the scientific or clinical basis for, or results or degree of success of, their services; (7) their fees; or (8) their publications or research findings.

(c) Psychologists claim degrees as credentials for their health services only if those degrees (1) were earned from a regionally accredited educational institution or (2) were the basis for psychology licensure by the state in which they practice.

5.02 Statements by Others (a) Psychologists who engage others to create or place public statements that promote their professional practice, products, or activities retain professional responsibility for such statements.

(b) Psychologists do not compensate employees of press, radio, television, or other communication media in return for publicity in a news item. (See also Standard 1.01, Misuse of Psychologists' Work .)

(c) A paid advertisement relating to psychologists' activities must be identified or clearly recognizable as such.

5.03 Descriptions of Workshops and Non-Degree-Granting Educational Programs To the degree to which they exercise control, psychologists responsible for announcements, catalogs, brochures, or advertisements describing workshops, seminars, or other non-degree-granting educational programs ensure that they accurately describe the audience for which the program is intended, the educational objectives, the presenters, and the fees involved.

5.04 Media Presentations When psychologists provide public advice or comment via print, Internet, or other electronic transmission, they take precautions to ensure that statements (1) are based on their professional knowledge, training, or experience in accord with appropriate psychological literature and practice; (2) are otherwise consistent with this Ethics Code; and (3) do not indicate that a professional relationship has been established with the recipient. (See also Standard 2.04, Bases for Scientific and Professional Judgments .)

5.05 Testimonials Psychologists do not solicit testimonials from current therapy clients/patients or other persons who because of their particular circumstances are vulnerable to undue influence.

5.06 In-Person Solicitation Psychologists do not engage, directly or through agents, in uninvited in-person solicitation of business from actual or potential therapy clients/patients or other persons who because of their particular circumstances are vulnerable to undue influence. However, this prohibition does not preclude (1) attempting to implement appropriate collateral contacts for the purpose of benefiting an already engaged therapy client/patient or (2) providing disaster or community outreach services.

6.01 Documentation of Professional and Scientific Work and Maintenance of Records Psychologists create, and to the extent the records are under their control, maintain, disseminate, store, retain, and dispose of records and data relating to their professional and scientific work in order to (1) facilitate provision of services later by them or by other professionals, (2) allow for replication of research design and analyses, (3) meet institutional requirements, (4) ensure accuracy of billing and payments, and (5) ensure compliance with law. (See also Standard 4.01, Maintaining Confidentiality .)

6.02 Maintenance, Dissemination, and Disposal of Confidential Records of Professional and Scientific Work (a) Psychologists maintain confidentiality in creating, storing, accessing, transferring, and disposing of records under their control, whether these are written, automated, or in any other medium. (See also Standards 4.01, Maintaining Confidentiality , and 6.01, Documentation of Professional and Scientific Work and Maintenance of Records .)

(b) If confidential information concerning recipients of psychological services is entered into databases or systems of records available to persons whose access has not been consented to by the recipient, psychologists use coding or other techniques to avoid the inclusion of personal identifiers.

(c) Psychologists make plans in advance to facilitate the appropriate transfer and to protect the confidentiality of records and data in the event of psychologists' withdrawal from positions or practice. (See also Standards 3.12, Interruption of Psychological Services , and 10.09, Interruption of Therapy .)

6.03 Withholding Records for Nonpayment Psychologists may not withhold records under their control that are requested and needed for a client's/patient's emergency treatment solely because payment has not been received.

6.04 Fees and Financial Arrangements (a) As early as is feasible in a professional or scientific relationship, psychologists and recipients of psychological services reach an agreement specifying compensation and billing arrangements.

(b) Psychologists' fee practices are consistent with law.

(c) Psychologists do not misrepresent their fees.

(d) If limitations to services can be anticipated because of limitations in financing, this is discussed with the recipient of services as early as is feasible. (See also Standards 10.09, Interruption of Therapy , and 10.10, Terminating Therapy .)

(e) If the recipient of services does not pay for services as agreed, and if psychologists intend to use collection agencies or legal measures to collect the fees, psychologists first inform the person that such measures will be taken and provide that person an opportunity to make prompt payment. (See also Standards 4.05, Disclosures ; 6.03, Withholding Records for Nonpayment ; and 10.01, Informed Consent to Therapy .)

6.05 Barter with Clients/Patients Barter is the acceptance of goods, services, or other nonmonetary remuneration from clients/patients in return for psychological services. Psychologists may barter only if (1) it is not clinically contraindicated, and (2) the resulting arrangement is not exploitative. (See also Standards 3.05, Multiple Relationships , and 6.04, Fees and Financial Arrangements .)

6.06 Accuracy in Reports to Payors and Funding Sources In their reports to payors for services or sources of research funding, psychologists take reasonable steps to ensure the accurate reporting of the nature of the service provided or research conducted, the fees, charges, or payments, and where applicable, the identity of the provider, the findings, and the diagnosis. (See also Standards 4.01, Maintaining Confidentiality ; 4.04, Minimizing Intrusions on Privacy ; and 4.05, Disclosures .)

6.07 Referrals and Fees When psychologists pay, receive payment from, or divide fees with another professional, other than in an employer-employee relationship, the payment to each is based on the services provided (clinical, consultative, administrative, or other) and is not based on the referral itself. (See also Standard 3.09, Cooperation with Other Professionals .)

7.01 Design of Education and Training Programs Psychologists responsible for education and training programs take reasonable steps to ensure that the programs are designed to provide the appropriate knowledge and proper experiences, and to meet the requirements for licensure, certification, or other goals for which claims are made by the program. (See also Standard 5.03, Descriptions of Workshops and Non-Degree-Granting Educational Programs .)

7.02 Descriptions of Education and Training Programs Psychologists responsible for education and training programs take reasonable steps to ensure that there is a current and accurate description of the program content (including participation in required course- or program-related counseling, psychotherapy, experiential groups, consulting projects, or community service), training goals and objectives, stipends and benefits, and requirements that must be met for satisfactory completion of the program. This information must be made readily available to all interested parties.

7.03 Accuracy in Teaching (a) Psychologists take reasonable steps to ensure that course syllabi are accurate regarding the subject matter to be covered, bases for evaluating progress, and the nature of course experiences. This standard does not preclude an instructor from modifying course content or requirements when the instructor considers it pedagogically necessary or desirable, so long as students are made aware of these modifications in a manner that enables them to fulfill course requirements. (See also Standard 5.01, Avoidance of False or Deceptive Statements .)

(b) When engaged in teaching or training, psychologists present psychological information accurately. (See also Standard 2.03, Maintaining Competence .)

7.04 Student Disclosure of Personal Information Psychologists do not require students or supervisees to disclose personal information in course- or program-related activities, either orally or in writing, regarding sexual history, history of abuse and neglect, psychological treatment, and relationships with parents, peers, and spouses or significant others except if (1) the program or training facility has clearly identified this requirement in its admissions and program materials or (2) the information is necessary to evaluate or obtain assistance for students whose personal problems could reasonably be judged to be preventing them from performing their training- or professionally related activities in a competent manner or posing a threat to the students or others.

7.05 Mandatory Individual or Group Therapy (a) When individual or group therapy is a program or course requirement, psychologists responsible for that program allow students in undergraduate and graduate programs the option of selecting such therapy from practitioners unaffiliated with the program. (See also Standard 7.02, Descriptions of Education and Training Programs .)

(b) Faculty who are or are likely to be responsible for evaluating students' academic performance do not themselves provide that therapy. (See also Standard 3.05, Multiple Relationships .)

7.06 Assessing Student and Supervisee Performance (a) In academic and supervisory relationships, psychologists establish a timely and specific process for providing feedback to students and supervisees. Information regarding the process is provided to the student at the beginning of supervision.

(b) Psychologists evaluate students and supervisees on the basis of their actual performance on relevant and established program requirements.

7.07 Sexual Relationships with Students and Supervisees Psychologists do not engage in sexual relationships with students or supervisees who are in their department, agency, or training center or over whom psychologists have or are likely to have evaluative authority. (See also Standard 3.05, Multiple Relationships .)

8.01 Institutional Approval When institutional approval is required, psychologists provide accurate information about their research proposals and obtain approval prior to conducting the research. They conduct the research in accordance with the approved research protocol.

8.02 Informed Consent to Research (a) When obtaining informed consent as required in Standard 3.10, Informed Consent, psychologists inform participants about (1) the purpose of the research, expected duration, and procedures; (2) their right to decline to participate and to withdraw from the research once participation has begun; (3) the foreseeable consequences of declining or withdrawing; (4) reasonably foreseeable factors that may be expected to influence their willingness to participate such as potential risks, discomfort, or adverse effects; (5) any prospective research benefits; (6) limits of confidentiality; (7) incentives for participation; and (8) whom to contact for questions about the research and research participants' rights. They provide opportunity for the prospective participants to ask questions and receive answers. (See also Standards 8.03, Informed Consent for Recording Voices and Images in Research ; 8.05, Dispensing with Informed Consent for Research ; and 8.07, Deception in Research .)

(b) Psychologists conducting intervention research involving the use of experimental treatments clarify to participants at the outset of the research (1) the experimental nature of the treatment; (2) the services that will or will not be available to the control group(s) if appropriate; (3) the means by which assignment to treatment and control groups will be made; (4) available treatment alternatives if an individual does not wish to participate in the research or wishes to withdraw once a study has begun; and (5) compensation for or monetary costs of participating including, if appropriate, whether reimbursement from the participant or a third-party payor will be sought. (See also Standard 8.02a, Informed Consent to Research .)

8.03 Informed Consent for Recording Voices and Images in Research Psychologists obtain informed consent from research participants prior to recording their voices or images for data collection unless (1) the research consists solely of naturalistic observations in public places, and it is not anticipated that the recording will be used in a manner that could cause personal identification or harm, or (2) the research design includes deception, and consent for the use of the recording is obtained during debriefing. (See also Standard 8.07, Deception in Research .)

8.04 Client/Patient, Student, and Subordinate Research Participants (a) When psychologists conduct research with clients/patients, students, or subordinates as participants, psychologists take steps to protect the prospective participants from adverse consequences of declining or withdrawing from participation.

(b) When research participation is a course requirement or an opportunity for extra credit, the prospective participant is given the choice of equitable alternative activities.

8.05 Dispensing with Informed Consent for Research Psychologists may dispense with informed consent only (1) where research would not reasonably be assumed to create distress or harm and involves (a) the study of normal educational practices, curricula, or classroom management methods conducted in educational settings; (b) only anonymous questionnaires, naturalistic observations, or archival research for which disclosure of responses would not place participants at risk of criminal or civil liability or damage their financial standing, employability, or reputation, and confidentiality is protected; or (c) the study of factors related to job or organization effectiveness conducted in organizational settings for which there is no risk to participants' employability, and confidentiality is protected or (2) where otherwise permitted by law or federal or institutional regulations.

8.06 Offering Inducements for Research Participation (a) Psychologists make reasonable efforts to avoid offering excessive or inappropriate financial or other inducements for research participation when such inducements are likely to coerce participation.

(b) When offering professional services as an inducement for research participation, psychologists clarify the nature of the services, as well as the risks, obligations, and limitations. (See also Standard 6.05, Barter with Clients/Patients .)

8.07 Deception in Research (a) Psychologists do not conduct a study involving deception unless they have determined that the use of deceptive techniques is justified by the study's significant prospective scientific, educational, or applied value and that effective nondeceptive alternative procedures are not feasible.

(b) Psychologists do not deceive prospective participants about research that is reasonably expected to cause physical pain or severe emotional distress.

(c) Psychologists explain any deception that is an integral feature of the design and conduct of an experiment to participants as early as is feasible, preferably at the conclusion of their participation, but no later than at the conclusion of the data collection, and permit participants to withdraw their data. (See also Standard 8.08, Debriefing .)

8.08 Debriefing (a) Psychologists provide a prompt opportunity for participants to obtain appropriate information about the nature, results, and conclusions of the research, and they take reasonable steps to correct any misconceptions that participants may have of which the psychologists are aware.

(b) If scientific or humane values justify delaying or withholding this information, psychologists take reasonable measures to reduce the risk of harm.

(c) When psychologists become aware that research procedures have harmed a participant, they take reasonable steps to minimize the harm.

8.09 Humane Care and Use of Animals in Research (a) Psychologists acquire, care for, use, and dispose of animals in compliance with current federal, state, and local laws and regulations, and with professional standards.

(b) Psychologists trained in research methods and experienced in the care of laboratory animals supervise all procedures involving animals and are responsible for ensuring appropriate consideration of their comfort, health, and humane treatment.

(c) Psychologists ensure that all individuals under their supervision who are using animals have received instruction in research methods and in the care, maintenance, and handling of the species being used, to the extent appropriate to their role. (See also Standard 2.05, Delegation of Work to Others .)

(d) Psychologists make reasonable efforts to minimize the discomfort, infection, illness, and pain of animal subjects.

(e) Psychologists use a procedure subjecting animals to pain, stress, or privation only when an alternative procedure is unavailable and the goal is justified by its prospective scientific, educational, or applied value.

(f) Psychologists perform surgical procedures under appropriate anesthesia and follow techniques to avoid infection and minimize pain during and after surgery.

(g) When it is appropriate that an animal's life be terminated, psychologists proceed rapidly, with an effort to minimize pain and in accordance with accepted procedures.

8.10 Reporting Research Results (a) Psychologists do not fabricate data. (See also Standard 5.01a, Avoidance of False or Deceptive Statements .)

(b) If psychologists discover significant errors in their published data, they take reasonable steps to correct such errors in a correction, retraction, erratum, or other appropriate publication means.

8.11 Plagiarism Psychologists do not present portions of another's work or data as their own, even if the other work or data source is cited occasionally.

8.12 Publication Credit (a) Psychologists take responsibility and credit, including authorship credit, only for work they have actually performed or to which they have substantially contributed. (See also Standard 8.12b, Publication Credit .)

(b) Principal authorship and other publication credits accurately reflect the relative scientific or professional contributions of the individuals involved, regardless of their relative status. Mere possession of an institutional position, such as department chair, does not justify authorship credit. Minor contributions to the research or to the writing for publications are acknowledged appropriately, such as in footnotes or in an introductory statement.

(c) Except under exceptional circumstances, a student is listed as principal author on any multiple-authored article that is substantially based on the student's doctoral dissertation. Faculty advisors discuss publication credit with students as early as feasible and throughout the research and publication process as appropriate. (See also Standard 8.12b, Publication Credit .)

8.13 Duplicate Publication of Data Psychologists do not publish, as original data, data that have been previously published. This does not preclude republishing data when they are accompanied by proper acknowledgment.

8.14 Sharing Research Data for Verification (a) After research results are published, psychologists do not withhold the data on which their conclusions are based from other competent professionals who seek to verify the substantive claims through reanalysis and who intend to use such data only for that purpose, provided that the confidentiality of the participants can be protected and unless legal rights concerning proprietary data preclude their release. This does not preclude psychologists from requiring that such individuals or groups be responsible for costs associated with the provision of such information.

(b) Psychologists who request data from other psychologists to verify the substantive claims through reanalysis may use shared data only for the declared purpose. Requesting psychologists obtain prior written agreement for all other uses of the data.

8.15 Reviewers Psychologists who review material submitted for presentation, publication, grant, or research proposal review respect the confidentiality of and the proprietary rights in such information of those who submitted it.

9.01 Bases for Assessments (a) Psychologists base the opinions contained in their recommendations, reports, and diagnostic or evaluative statements, including forensic testimony, on information and techniques sufficient to substantiate their findings. (See also Standard 2.04, Bases for Scientific and Professional Judgments .)

(b) Except as noted in 9.01c , psychologists provide opinions of the psychological characteristics of individuals only after they have conducted an examination of the individuals adequate to support their statements or conclusions. When, despite reasonable efforts, such an examination is not practical, psychologists document the efforts they made and the result of those efforts, clarify the probable impact of their limited information on the reliability and validity of their opinions, and appropriately limit the nature and extent of their conclusions or recommendations. (See also Standards 2.01, Boundaries of Competence , and 9.06, Interpreting Assessment Results .)

(c) When psychologists conduct a record review or provide consultation or supervision and an individual examination is not warranted or necessary for the opinion, psychologists explain this and the sources of information on which they based their conclusions and recommendations.

9.02 Use of Assessments (a) Psychologists administer, adapt, score, interpret, or use assessment techniques, interviews, tests, or instruments in a manner and for purposes that are appropriate in light of the research on or evidence of the usefulness and proper application of the techniques.

(b) Psychologists use assessment instruments whose validity and reliability have been established for use with members of the population tested. When such validity or reliability has not been established, psychologists describe the strengths and limitations of test results and interpretation.

(c) Psychologists use assessment methods that are appropriate to an individual's language preference and competence, unless the use of an alternative language is relevant to the assessment issues.

9.03 Informed Consent in Assessments (a) Psychologists obtain informed consent for assessments, evaluations, or diagnostic services, as described in Standard 3.10, Informed Consent, except when (1) testing is mandated by law or governmental regulations; (2) informed consent is implied because testing is conducted as a routine educational, institutional, or organizational activity (e.g., when participants voluntarily agree to assessment when applying for a job); or (3) one purpose of the testing is to evaluate decisional capacity. Informed consent includes an explanation of the nature and purpose of the assessment, fees, involvement of third parties, and limits of confidentiality and sufficient opportunity for the client/patient to ask questions and receive answers.

(b) Psychologists inform persons with questionable capacity to consent or for whom testing is mandated by law or governmental regulations about the nature and purpose of the proposed assessment services, using language that is reasonably understandable to the person being assessed.

(c) Psychologists using the services of an interpreter obtain informed consent from the client/patient to use that interpreter, ensure that confidentiality of test results and test security are maintained, and include in their recommendations, reports, and diagnostic or evaluative statements, including forensic testimony, discussion of any limitations on the data obtained. (See also Standards 2.05, Delegation of Work to Others ; 4.01, Maintaining Confidentiality ; 9.01, Bases for Assessments ; 9.06, Interpreting Assessment Results ; and 9.07, Assessment by Unqualified Persons .)

9.04 Release of Test Data (a) The term test data refers to raw and scaled scores, client/patient responses to test questions or stimuli, and psychologists' notes and recordings concerning client/patient statements and behavior during an examination. Those portions of test materials that include client/patient responses are included in the definition of test data . Pursuant to a client/patient release, psychologists provide test data to the client/patient or other persons identified in the release. Psychologists may refrain from releasing test data to protect a client/patient or others from substantial harm or misuse or misrepresentation of the data or the test, recognizing that in many instances release of confidential information under these circumstances is regulated by law. (See also Standard 9.11, Maintaining Test Security .)

(b) In the absence of a client/patient release, psychologists provide test data only as required by law or court order.

9.05 Test Construction Psychologists who develop tests and other assessment techniques use appropriate psychometric procedures and current scientific or professional knowledge for test design, standardization, validation, reduction or elimination of bias, and recommendations for use.

9.06 Interpreting Assessment Results When interpreting assessment results, including automated interpretations, psychologists take into account the purpose of the assessment as well as the various test factors, test-taking abilities, and other characteristics of the person being assessed, such as situational, personal, linguistic, and cultural differences, that might affect psychologists' judgments or reduce the accuracy of their interpretations. They indicate any significant limitations of their interpretations. (See also Standards 2.01b and c, Boundaries of Competence , and 3.01, Unfair Discrimination .)

9.07 Assessment by Unqualified Persons Psychologists do not promote the use of psychological assessment techniques by unqualified persons, except when such use is conducted for training purposes with appropriate supervision. (See also Standard 2.05, Delegation of Work to Others .)

9.08 Obsolete Tests and Outdated Test Results (a) Psychologists do not base their assessment or intervention decisions or recommendations on data or test results that are outdated for the current purpose.

(b) Psychologists do not base such decisions or recommendations on tests and measures that are obsolete and not useful for the current purpose.

9.09 Test Scoring and Interpretation Services (a) Psychologists who offer assessment or scoring services to other professionals accurately describe the purpose, norms, validity, reliability, and applications of the procedures and any special qualifications applicable to their use.

(b) Psychologists select scoring and interpretation services (including automated services) on the basis of evidence of the validity of the program and procedures as well as on other appropriate considerations. (See also Standard 2.01b and c, Boundaries of Competence .)

(c) Psychologists retain responsibility for the appropriate application, interpretation, and use of assessment instruments, whether they score and interpret such tests themselves or use automated or other services.

9.10 Explaining Assessment Results Regardless of whether the scoring and interpretation are done by psychologists, by employees or assistants, or by automated or other outside services, psychologists take reasonable steps to ensure that explanations of results are given to the individual or designated representative unless the nature of the relationship precludes provision of an explanation of results (such as in some organizational consulting, preemployment or security screenings, and forensic evaluations), and this fact has been clearly explained to the person being assessed in advance.

9.11 Maintaining Test Security The term test materials refers to manuals, instruments, protocols, and test questions or stimuli and does not include test data as defined in Standard 9.04, Release of Test Data . Psychologists make reasonable efforts to maintain the integrity and security of test materials and other assessment techniques consistent with law and contractual obligations, and in a manner that permits adherence to this Ethics Code.

10.01 Informed Consent to Therapy (a) When obtaining informed consent to therapy as required in Standard 3.10, Informed Consent , psychologists inform clients/patients as early as is feasible in the therapeutic relationship about the nature and anticipated course of therapy, fees, involvement of third parties, and limits of confidentiality and provide sufficient opportunity for the client/patient to ask questions and receive answers. (See also Standards 4.02, Discussing the Limits of Confidentiality , and 6.04, Fees and Financial Arrangements .)

(b) When obtaining informed consent for treatment for which generally recognized techniques and procedures have not been established, psychologists inform their clients/patients of the developing nature of the treatment, the potential risks involved, alternative treatments that may be available, and the voluntary nature of their participation. (See also Standards 2.01e, Boundaries of Competence , and 3.10, Informed Consent .)

(c) When the therapist is a trainee and the legal responsibility for the treatment provided resides with the supervisor, the client/patient, as part of the informed consent procedure, is informed that the therapist is in training and is being supervised and is given the name of the supervisor.

10.02 Therapy Involving Couples or Families (a) When psychologists agree to provide services to several persons who have a relationship (such as spouses, significant others, or parents and children), they take reasonable steps to clarify at the outset (1) which of the individuals are clients/patients and (2) the relationship the psychologist will have with each person. This clarification includes the psychologist's role and the probable uses of the services provided or the information obtained. (See also Standard 4.02, Discussing the Limits of Confidentiality .)

(b) If it becomes apparent that psychologists may be called on to perform potentially conflicting roles (such as family therapist and then witness for one party in divorce proceedings), psychologists take reasonable steps to clarify and modify, or withdraw from, roles appropriately. (See also Standard 3.05c, Multiple Relationships .)

10.03 Group Therapy When psychologists provide services to several persons in a group setting, they describe at the outset the roles and responsibilities of all parties and the limits of confidentiality.

10.04 Providing Therapy to Those Served by Others In deciding whether to offer or provide services to those already receiving mental health services elsewhere, psychologists carefully consider the treatment issues and the potential client's/patient's welfare. Psychologists discuss these issues with the client/patient or another legally authorized person on behalf of the client/patient in order to minimize the risk of confusion and conflict, consult with the other service providers when appropriate, and proceed with caution and sensitivity to the therapeutic issues.

10.05 Sexual Intimacies with Current Therapy Clients/Patients Psychologists do not engage in sexual intimacies with current therapy clients/patients.

10.06 Sexual Intimacies with Relatives or Significant Others of Current Therapy Clients/Patients Psychologists do not engage in sexual intimacies with individuals they know to be close relatives, guardians, or significant others of current clients/patients. Psychologists do not terminate therapy to circumvent this standard.

10.07 Therapy with Former Sexual Partners Psychologists do not accept as therapy clients/patients persons with whom they have engaged in sexual intimacies.

10.08 Sexual Intimacies with Former Therapy Clients/Patients (a) Psychologists do not engage in sexual intimacies with former clients/patients for at least two years after cessation or termination of therapy.

(b) Psychologists do not engage in sexual intimacies with former clients/patients even after a two-year interval except in the most unusual circumstances. Psychologists who engage in such activity after the two years following cessation or termination of therapy and of having no sexual contact with the former client/patient bear the burden of demonstrating that there has been no exploitation, in light of all relevant factors, including (1) the amount of time that has passed since therapy terminated; (2) the nature, duration, and intensity of the therapy; (3) the circumstances of termination; (4) the client's/patient's personal history; (5) the client's/patient's current mental status; (6) the likelihood of adverse impact on the client/patient; and (7) any statements or actions made by the therapist during the course of therapy suggesting or inviting the possibility of a posttermination sexual or romantic relationship with the client/patient. (See also Standard 3.05, Multiple Relationships .)

10.09 Interruption of Therapy When entering into employment or contractual relationships, psychologists make reasonable efforts to provide for orderly and appropriate resolution of responsibility for client/patient care in the event that the employment or contractual relationship ends, with paramount consideration given to the welfare of the client/patient. (See also Standard 3.12, Interruption of Psychological Services .)

10.10 Terminating Therapy (a) Psychologists terminate therapy when it becomes reasonably clear that the client/patient no longer needs the service, is not likely to benefit, or is being harmed by continued service.

(b) Psychologists may terminate therapy when threatened or otherwise endangered by the client/patient or another person with whom the client/patient has a relationship.

(c) Except where precluded by the actions of clients/patients or third-party payors, prior to termination psychologists provide pretermination counseling and suggest alternative service providers as appropriate.

The American Psychological Association’s  Council of Representatives  adopted this version of the APA Ethics Code during its meeting on Aug. 21, 2002. The Code became effective on June 1, 2003. The Council of Representatives amended this version of the Ethics Code on Feb. 20, 2010, effective June 1, 2010, and on Aug. 3, 2016, effective Jan. 1, 2017.  Inquiries concerning the substance or interpretation of the APA Ethics Code should be addressed to the Director, Office of Ethics, American Psychological Association, 750 First St. NE, Washington, DC 20002-4242. The standards in this Ethics Code will be used to adjudicate complaints brought concerning alleged conduct occurring on or after the effective date. Complaints will be adjudicated on the basis of the version of the Ethics Code that was in effect at the time the conduct occurred.

The APA has previously published its Ethics Code as follows:

American Psychological Association. (1953). Ethical standards of psychologists . Washington, DC: Author.

American Psychological Association. (1959). Ethical standards of psychologists. American Psychologist , 14 , 279-282.

American Psychological Association. (1963). Ethical standards of psychologists. American Psychologist , 18 , 56-60.

American Psychological Association. (1968). Ethical standards of psychologists. American Psychologist , 23 , 357-361.

American Psychological Association. (1977, March). Ethical standards of psychologists. APA Monitor , 22-23.

American Psychological Association. (1979). Ethical standards of psychologists . Washington, DC: Author.

American Psychological Association. (1981). Ethical principles of psychologists. American Psychologist , 36 , 633-638.

American Psychological Association. (1990). Ethical principles of psychologists (Amended June 2, 1989). American Psychologist , 45 , 390-395.

American Psychological Association. (1992). Ethical principles of psychologists and code of conduct. American Psychologist , 47 , 1597-1611.

American Psychological Association. (2002). Ethical principles of psychologists and code of conduct. American Psychologist , 57 , 1060-1073.

American Psychological Association. (2010). 2010 amendments to the 2002 “ Ethical Principles of Psychologists and Code of Conduct. ” American Psychologist , 65 , 493.

American Psychological Association. (2016). Revision of ethical standard 3.04 of the “ Ethical Principles of Psychologists and Code of Conduct ” (2002, as amended 2010). American Psychologist , 71 , 900.

Request copies of the APA's Ethical Principles of Psychologists and Code of Conduct from the APA Order Department, 750 First St. NE, Washington, DC 20002-4242, or phone (202) 336-5510.

2010 Amendments

Introduction and Applicability If psychologists’ ethical responsibilities conflict with law, regulations, or other governing legal authority, psychologists make known their commitment to this Ethics Code and take steps to resolve the conflict in a responsible manner . If the conflict is unresolvable via such means, psychologists may adhere to the requirements of the law, regulations, or other governing authority in keeping with basic principles of human rights.

1.02 Conflicts Between Ethics and Law, Regulations, or Other Governing Legal Authority If psychologists’ ethical responsibilities conflict with law, regulations, or other governing legal authority, psychologists clarify the nature of the conflict , make known their commitment to the Ethics Code, and take reasonable steps to resolve the conflict consistent with the General Principles and Ethical Standards of the Ethics Code . If the conflict is unresolvable via such means, psychologists may adhere to the requirements of the law, regulations, or other governing legal authority. Under no circumstances may this standard be used to justify or defend violating human rights .

1.03 Conflicts Between Ethics and Organizational Demands If the demands of an organization with which psychologists are affiliated or for whom they are working are in conflict with this Ethics Code, psychologists clarify the nature of the conflict, make known their commitment to the Ethics Code, and to the extent feasible, resolve the conflict in a way that permits adherence to the Ethics Code. take reasonable steps to resolve the conflict consistent with the General Principles and Ethical Standards of the Ethics Code. Under no circumstances may this standard be used to justify or defend violating human rights .

2016 Amendment

3.04 Avoiding Harm (a) Psychologists take reasonable steps to avoid harming their clients/patients, students, supervisees, research participants, organizational clients, and others with whom they work, and to minimize harm where it is foreseeable and unavoidable. 

Additional Resources

2018 APA Ethics Committee Rules and Procedures (PDF, 197KB)

Revision of Ethics Code Standard 3.04 (Avoiding Harm) 

APA Ethical Principles of Psychologists and Code of Conduct (2017) (PDF, 272KB)

2016 APA Ethics Committee Rules and Procedures

Revision of Ethical Standard 3.04 of the “Ethical Principles of Psychologists and Code of Conduct” (2002, as Amended 2010) (PDF, 26KB)

2010 Amendments to the 2002 "Ethical Principles of Psychologists and Code of Conduct" (PDF, 39KB)

Compare the 1992 and 2002 Ethics Codes

Contact APA Ethics Office

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Understanding Science

How science REALLY works...

• Understanding Science 101
• Misconceptions

Scientific ideas can be tested through both experiments and other sorts of studies. Both provide important sources of evidence.

Misconception:  Experiments are a necessary part of the scientific process. Without an experiment, a study is not rigorous or scientific.

Correction:  Scientific testing involves more than just experiments. There are many valid ways to test scientific ideas and the appropriate method depends on many factors.  Read more about it.

Tactics for testing ideas

Experiments are one way to test some sorts of ideas, but science doesn’t live on experiment alone. There are many other ways to scientifically test ideas too…

What are experiments?

An experiment is a test that involves manipulating some factor in a system in order to see how that affects the outcome. Ideally, experiments also involve controlling as many other factors as possible in order to isolate the cause of the experimental results. Experiments can be simple tests set up in a lab, like rolling a ball down different inclines to see how the angle affects the rolling time. But large-scale experiments can also be performed out in the real world. For example, classic experiments in ecology involved removing a species of barnacles from intertidal rocks on the Scottish coast to see how that would affect other barnacle species over time. But whether they are large- or small-scale, performed in the lab or in the field, and require years or mere milliseconds to complete, experiments are distinguished from other sorts of tests by their reliance on the intentional manipulation of some factors and, ideally, the control of others.

Beyond experiments: Observational studies and natural experiments

Some aspects of the natural world aren’t manipulable, and hence can’t be studied with direct experiments. We simply can’t go back in time and introduce finches to three separate island groups to see how they evolve. We can’t move the planets around to see how their orbits would be altered by a new configuration. And we can’t cause volcanoes to erupt in order to investigate how they affect the ecosystems that surround them. Other times, it would be unethical to perform an experiment – for example, to investigate the effect of maternal alcohol consumption on babies.

In such cases, we can still figure out what expectations a hypothesis generates and make observations to test the idea. For example, we can’t actually experiment on distant stars in order to test ideas about which nuclear reactions occur within them, but we can test those ideas by building sensors that allow us to observe what forms of radiation the stars emit. Similarly, we can’t perform experiments to test ideas about what T. rex ate, but we can test those ideas by making detailed observations of their fossilized teeth and comparing those to the teeth of modern organisms that eat different foods. And of course, many ideas can be tested by both experiment and through straightforward observation. For example, we can test ideas about how chlorofluorocarbons interact with the ozone layer by performing chemical experiments in a lab and through observational studies of the atmosphere.

In some cases, we get lucky and are able to take advantage of a natural experiment . Natural experiments occur when the universe, in a sense, performs an experiment for us — that is, the relevant experimental set-up already exists, and all we have to do is observe the results. For example, researchers in England wanted to know if a program to improve the health and well-being of young children and their families was effective. Enrolling some children in the program and randomly excluding others to create a controlled experiment would be unethical. However, for other reasons, the program was rolled out in some geographic areas, but not in others. This set up a natural experiment that the researchers could take advantage of by comparing outcomes in families who received the program with outcomes in similar families who did not receive the program. Analyzing the results of this natural experiment suggested that the program helped children develop socially, encouraged families to build better learning environments for their kids, and discouraged poor parenting.

• Take a sidetrip

To learn how a natural experiment provides support for the  theory  of general relativity, take an advanced side trip to  Illuminating relativity: Experimenting with the stars .

• Science in action

What happens when you can’t do an experiment? There are plenty of other ways to test scientific ideas. To see how observational studies factor into the process of science, check out these stories:

• Asteroids and dinosaurs
• Cells within cells: An extraordinary claim with extraordinary evidence
• Here, we’ve talked about the different ways to test scientific ideas with evidence, but what makes a fair test? To learn more, take an advanced side trip to  Fair tests: A do-it-yourself guide .
• Visit the Visionlearning website for  advanced material on experimentation  and other methods of testing scientific ideas, like  description ,  comparison , and  modeling .

The logic of scientific arguments

Digging into data

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