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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:

The 10 Cruelest Human Experimentation Cases 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.

10 Outrageous Experiments Conducted on Humans

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Prisoners, the disabled, the physically and mentally sick, the poor -- these are all groups once considered fair game to use as subjects in your research experiments. And if you didn't want to get permission, you didn't have to, and many doctors and researchers conducted their experiments on people who were unwilling to participate or who were unknowingly participating.

Forty years ago the U.S. Congress changed the rules; informed consent is now required for any government-funded medical study involving human subjects. But before 1974 the ethics involved in using humans in research experiments was a little, let's say, loose. And the exploitation and abuse of human subjects was often alarming. We begin our list with one of the most famous instances of exploitation, a study that eventually helped change the public view about the lack of consent in the name of scientific advancements.

Tuskegee Syphilis Study
The Nazi Medical Experiments
Watson's 'Little Albert' Experiment
The Monster Study of 1939
Stateville Penitentiary Malaria Study
The Aversion Project in South Africa
Milgram Shock Experiments
CIA Mind-Control Experiments (Project MK-Ultra)
The Human Vivisections of Herophilus

10: Tuskegee Syphilis Study

Syphilis was a major public health problem in the 1920s, and in 1928 the Julius Rosenwald Fund, a charity organization, launched a public healthcare project for blacks in the American rural south. Sounds good, right? It was, until the Great Depression rocked the U.S. in 1929 and the project lost its funding. Changes were made to the program; instead of treating health problems in underserved areas, in 1932 poor black men living in Macon County, Alabama, were instead enrolled in a program to treat what they were told was their "bad blood" (a term that, at the time, was used in reference to everything from anemia to fatigue to syphilis). They were given free medical care, as well as food and other amenities such as burial insurance, for participating in the study. But they didn't know it was all a sham. The men in the study weren't told that they were recruited for the program because they were actually suffering from the sexually transmitted disease syphilis, nor were they told they were taking part in a government experiment studying untreated syphilis, the "Tuskegee Study of Untreated Syphilis in the Negro Male." That's right: untreated.

Despite thinking they were receiving medical care, subjects were never actually properly treated for the disease. This went on even after penicillin hit the scene and became the go-to treatment for the infection in 1945, and after Rapid Treatment Centers were established in 1947. Despite concerns raised about the ethics of the Tuskegee Syphilis Study as early as 1936, the study didn't actually end until 1972 after the media reported on the multi-decade experiment and there was subsequent public outrage.

9: The Nazi Medical Experiments

During WWII, the Nazis performed medical experiments on adults and children imprisoned in the Dachau, Auschwitz, Buchenwald and Sachsenhausen concentration camps. The accounts of abuse, mutilation, starvation, and torture reads like a grisly compilation of all nine circles of hell. Prisoners in these death camps were subjected to heinous crimes under the guise of military advancement, medical and pharmaceutical advancement, and racial and population advancement.

Jews were subjected to experiments intended to benefit the military, including hypothermia studies where prisoners were immersed in ice water in an effort to ascertain how long a downed pilot could survive in similar conditions. Some victims were only allowed sea water, a study of how long pilots could survive at sea; these subjects, not surprisingly, died of dehydration. Victims were also exposed to high altitude in decompression chambers -- often followed with brain dissection on the living -- to study high-altitude sickness and how pilots would be affected by atmospheric pressure changes.

Effectively treating war injuries was also a concern for the Nazis, and pharmaceutical testing went on in these camps. Sulfanilamide was tested as a new treatment for war wounds. Victims were inflicted with wounds that were then intentionally infected. Infections and poisonings were also studied on human subjects. Tuberculosis (TB) was injected into prisoners in an effort to better understand how to immunize against the infection. Experiments with poison, to determine how fast subjects would die, were also on the agenda.

The Nazis also performed genetic and racially-motivated sterilizations, artificial inseminations, and also conducted experiments on twins and people of short stature.

8: Watson's 'Little Albert' Experiment

In 1920 John Watson, along with graduate student Rosalie Rayner, conducted an emotional-conditioning experiment on a nine-month-old baby -- whom they nicknamed "Albert B" -- at Johns Hopkins University in an effort to prove their theory that we're all born as blank slates that can be shaped. The child's mother, a wet nurse who worked at the hospital, was paid one dollar for allowing her son to take part.

The "Little Albert" experiment went like this: Researchers first introduced the baby to a small, furry white rat, of which he initially had no fear . (According to reports, he didn't really show much interest at all). Then they re-introduced him to the rat while a loud sound rang out. Over and over, "Albert" was exposed to the rat and startling noises until he became frightened any time he saw any small, furry animal (rats, for sure, but also dogs and monkeys) regardless of noise.

Who exactly "Albert" was remained unknown until 2010, when his identity was revealed to be Douglas Merritte. Merritte, it turns out, wasn't a healthy subject: He showed signs of behavioral and neurological impairment, never learned to talk or walk, and only lived to age six, dying from hydrocephalus (water on the brain). He also suffered from a bacterial meningitis infection he may have acquired accidentally during treatments for his hydrocephalus, or, as some theorize, may have been -- horrifyingly -- intentionally infected as part of another experiment.

In the end, Merritte was never deconditioned, and because he died at such a young age no one knows if he continued to fear small furry things post-experiment.

7: The Monster Study of 1939

Today we understand that stuttering has many possible causes. It may run in some families, an inherited genetic quirk of the language center of the brain. It may also occur because of a brain injury, including stroke or other trauma. Some young children stutter when they're learning to talk, but outgrow the problem. In some rare instances, it may be a side effect of emotional trauma. But you know what it's not caused by? Criticism.

In 1939 Mary Tudor, a graduate student at the University of Iowa, and her faculty advisor, speech expert Wendell Johnson, set out to prove stuttering could be taught through negative reinforcement -- that it's learned behavior. Over four months, 22 orphaned children were told they would be receiving speech therapy, but in reality they became subjects in a stuttering experiment; only about half were actually stutterers, and none received speech therapy.

During the experiment the children were split into four groups:

Half of the stutterers were given negative feedback.
The other half of stutterers were given positive feedback.
Half of the non-stuttering group were all told they were beginning to stutterer and were criticized.
The other half of non-stutterers were praised.

The only significant impact the experiment had was on that third group; these kids, despite never actually developing a stutter, began to change their behavior, exhibiting low self-esteem and adopting the self-conscious behaviors associated with stutterers. And those who did stutter didn't cease doing so regardless of the feedback they received.

6: Stateville Penitentiary Malaria Study

It's estimated that between 60 to 65 percent of American soldiers stationed in the South Pacific during WWII suffered from a malarial infection at some point during their service. For some units the infection proved to be more deadly than the enemy forces were, so finding an effective treatment was a high priority [source: Army Heritage Center Foundation]. Safe anti-malarial drugs were seen as essential to winning the war.

Beginning in 1944 and spanning over the course of two years, more than 400 prisoners at the Stateville Penitentiary in Illinois were subjects in an experiment aimed at finding an effective drug against malaria . Prisoners taking part in the experiment were infected with malaria, and then treated with experimental anti-malarial treatments. The experiment didn't have a hidden agenda, and its unethical methodology didn't seem to bother the American public, who were united in winning WWII and eager to bring the troops home — safe and healthy. The intent of the experiments wasn't hidden from the subjects, who were at the time praised for their patriotism and in many instances given shorter prison sentences in return for their participation.

5: The Aversion Project in South Africa

If you were living during the apartheid era in South Africa, you lived under state-regulated racial segregation. If that itself wasn't difficult enough, the state also controlled your sexuality.

The South African government upheld strict anti-homosexual laws. If you were gay you were considered a deviant — and your homosexuality was also considered a disease that could be treated. Even after homosexuality ceased to be considered a mental illness and aversion therapy as a way to cure it debunked, psychiatrists and Army medical professionals in the South African Defense Force (SADF) continued to believe the outdated theories and treatments. In particular, aversion therapy techniques were used on prisoners and on South Africans who were forced to join the military under the conscription laws of the time.

At Ward 22 at 1 Military hospital in Voortrekkerhoogte, Pretoria, between 1969 and 1987 attempts were made to "cure" perceived deviants. Homosexuals, gay men and lesbians were drugged and subjected to electroconvulsive behavior therapy while shown aversion stimuli (same-sex erotic photos), followed by erotic photos of the opposite sex after the electric shock. When the technique didn't work (and it absolutely didn't), victims were then treated with hormone therapy, which in some cases included chemical castration. In addition, an estimated 900 men and women also underwent gender reassignment surgery when subsequent efforts to "reorient" them failed — most without consent, and some left unfinished [source: Kaplan ].

4: Milgram Shock Experiments

Ghostbuster Peter Venkman, who is seen in the fictional film conducting ESP/electro-shock experiments on college students, was likely inspired by social psychologist Stanley Milgram's famous series of shock experiments conducted in the early 1960s. During Milgram's experiments "teachers" — Americans recruited for a Yale study they thought was about memory and learning — were told to read lists of words to "learners" (actors, although the teachers didn't know that). Each person in the teacher role was instructed to press a lever that would deliver a shock to their "learner" every time he made a mistake on word-matching quizzes. Teachers believed the voltage of shocks increased with each mistake, and ranged from 15 to 450 possible volts; roughly two-thirds of teachers shocked learners to the highest voltage , continuing to deliver jolts at the instruction of the experimenter.

In reality, this wasn't an experiment about memory and learning; rather, it was about how obedient we are to authority. No shocks were actually given.

Today, Milgram's shock experiments continue to be controversial; while they're criticized for their lack of realism, others point to the results as important to how humans behave when under duress. In 2010 the results of Milgram's study were repeated — with about 70 percent of teachers obediently administering what they believed to be the highest voltage shocks to their learners.

3: CIA Mind-Control Experiments (Project MK-Ultra)

If you're familiar with "Men Who Stare at Goats" or "The Manchurian Candidate" then you know: There was a period in the CIA's history when they performed covert mind-control experiments. If you thought it was fiction, it wasn't.

During the Cold War the CIA started researching ways they could turn Americans into CIA-controlled "superagents," people who could carry out assassinations and who wouldn't be affected by enemy interrogations. Under what was known as the MK-ULTRA project, CIA researchers experimented on unsuspecting American (and Canadian) citizens by slipping them psychedelic drugs, including LSD , PCP and barbiturates, as well as additional — and additionally illegal — methods such as hypnosis, and, possibly, chemical, biological, and radiological agents. Universities participated, mostly as a delivery system, also without their knowledge. The U.S. Department of Veterans Affairs estimates 7,000 soldiers were also involved in the research, without their consent.

The project endured for more than 20 years, during which the agency spent about $20 million. There was one death tied to the project, although more were suspected; tin 1973 the CIA destroyed what records were kept.

2: Unit 731

Using biological warfare was banned by the Geneva Protocol in 1925, but Japan rejected the ban. If germ warfare was effective enough to be banned, it must work, military leaders believed. Unit 731 , a secret unit in a secret facility — publicly known as the Epidemic Prevention and Water Supply Unit — was established in Japanese-controlled Manchuria, where by the mid-1930s Japan began experimenting with pathogenic and chemical warfare and testing on human subjects. There, military physicians and officers intentionally exposed victims to infectious diseases including anthrax , bubonic plague, cholera, syphilis, typhus and other pathogens, in an effort to understand how they affected the body and how they could be used in bombs and attacks in WWII.

In addition to working with pathogens, Unit 731 conducted experiments on people, including — but certainly not limited to — dissections and vivisections on living humans, all without anesthesia (the experimenters believed using it would skew the results of the research).

Many of the subjects were Chinese civilians and prisoners of war, but also included Russian and American victims among others — basically, anyone who wasn't Japanese was a potential subject. Today it's estimated that about 100,000 people were victims within the facility, but when you include the germ warfare field experiments (such as reports of Japanese planes dropping plague-infected fleas over Chinese villages and poisoning wells with cholera) the death toll climbs to estimates closer to 250,000, maybe more.

Believe it or not, after WWII the U.S. granted immunity to those involved in these war crimes committed at Unit 731 as part of an information exchange agreement — and until the 1980s, the Japanese government refused to admit any of this even happened.

1: The Human Vivisections of Herophilus

Ancient physician Herophilus is considered the father of anatomy. And while he made significant discoveries during his practice, it's how he learned about internal workings of the human body that lands him on this list.

Herophilus practiced medicine in Alexandria, Egypt, and during the reign of the first two Ptolemaio Pharoahs was allowed, at least for about 30 to 40 years, to dissect human bodies, which he did, publicly, along with contemporary Greek physician and anatomist Erasistratus. Under Ptolemy I and Ptolemy II, criminals could be sentenced to dissection and vivisection as punishment, and it's said the father of anatomy not only dissected the dead but also performed vivisection on an estimated 600 living prisoners [source: Elhadi ].

Herophilus made great strides in the study of human anatomy — especially the brain , eyes, liver, circulatory system, nervous system and reproductive system, during a time in history when dissecting human cadavers was considered an act of desecration of the body (there were no autopsies conducted on the dead, although mummification was popular in Egypt at the time). And, like today, performing vivisection on living bodies was considered butchery.

Frequently Asked Questions

How have these experiments influenced current ethical standards in research, what protections are in place today to prevent similar unethical research on humans, lots more information, author's note.

There is no denying that involving living, breathing humans in medical studies have produced some invaluable results, but there's that one medical saying most of us know, even if we're not in a medical field: first do no harm (or, if you're fancy, primum non nocere).

What will medicine consider unethical in 100 years?
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Milgram Experiment

The Monkey Drug Trials

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30 Most Unethical Psychology Human Experiments

Disturbing human experiments aren’t something the average person thinks too much about. Rather, the progress achieved in the last 150 years of human history is an accomplishment we’re reminded of almost daily. Achievements made in biomedicine and the f ield of psychology mean that we no longer need to worry about things like deadly diseases or masturbation as a form of insanity. For better or worse, we have developed more effective ways to gather information, treat skin abnormalities, and even kill each other. But what we are not constantly reminded of are the human lives that have been damaged or lost in the name of this progress. The following is a list of the 30 most disturbing human experiments in history.

30. The Tearoom Sex Study

Image Source Sociologist Laud Humphreys often wondered about the men who commit impersonal sexual acts with one another in public restrooms. He wondered why “tearoom sex” — fellatio in public restrooms — led to the majority of homosexual arrests in the United States. Humphreys decided to become a “watchqueen” (the person who keeps watch and coughs when a cop or stranger get near) for his Ph.D. dissertation at Washington University. Throughout his research, Humphreys observed hundreds of acts of fellatio and interviewed many of the participants. He found that 54% of his subjects were married, and 38% were very clearly neither bisexual or homosexual. Humphreys’ research shattered a number of stereotypes held by both the public and law enforcement.

29. Prison Inmates as Test Subjects

Image Source In 1951, Dr. Albert M. Kligman, a dermatologist at the University of Pennsylvania and future inventor of Retin-A, began experimenting on inmates at Philadelphia’s Holmesburg Prison. As Kligman later told a newspaper reporter, “All I saw before me were acres of skin. It was like a farmer seeing a field for the first time.” Over the next 20 years, inmates willingly allowed Kligman to use their bodies in experiments involving toothpaste, deodorant, shampoo, skin creams, detergents, liquid diets, eye drops, foot powders, and hair dyes. Though the tests required constant biopsies and painful procedures, none of the inmates experienced long-term harm.

28. Henrietta Lacks

Image Source In 1955, Henrietta Lacks, a poor, uneducated African-American woman from Baltimore, was the unwitting source of cells which where then cultured for the purpose of medical research. Though researchers had tried to grow cells before, Henrietta’s were the first successfully kept alive and cloned. Henrietta’s cells, known as HeLa cells, have been instrumental in the development of the polio vaccine, cancer research, AIDS research, gene mapping, and countless other scientific endeavors. Henrietta died penniless and was buried without a tombstone in a family cemetery. For decades, her husband and five children were left in the dark about their wife and mother’s amazing contribution to modern medicine.

27. Project QKHILLTOP

Image Source In 1954, the CIA developed an experiment called Project QKHILLTOP to study Chinese brainwashing techniques, which they then used to develop new methods of interrogation. Leading the research was Dr. Harold Wolff of Cornell University Medical School. After requesting that the CIA provide him with information on imprisonment, deprivation, humiliation, torture, brainwashing, hypnoses, and more, Wolff’s research team began to formulate a plan through which they would develop secret drugs and various brain damaging procedures. According to a letter he wrote, in order to fully test the effects of the harmful research, Wolff expected the CIA to “make available suitable subjects.”

26. Stateville Penitentiary Malaria Study

Image Source During World War II, malaria and other tropical diseases were impeding the efforts of American military in the Pacific. In order to get a grip, the Malaria Research Project was established at Stateville Penitentiary in Joliet, Illinois. Doctors from the University of Chicago exposed 441 volunteer inmates to bites from malaria-infected mosquitos. Though one inmate died of a heart attack, researchers insisted his death was unrelated to the study. The widely-praised experiment continued at Stateville for 29 years, and included the first human test of Primaquine, a medication still used in the treatment of malaria and Pneumocystis pneumonia.

25. Emma Eckstein and Sigmund Freud

Image Source Despite seeking the help of Sigmund Freud for vague symptoms like stomach ailments and slight depression, 27-year old Emma Eckstein was “treated” by the German doctor for hysteria and excessive masturbation, a habit then considered dangerous to mental health. Emma’s treatment included a disturbing experimental surgery in which she was anesthetized with only a local anesthetic and cocaine before the inside of her nose was cauterized. Not surprisingly, Emma’s surgery was a disaster. Whether Emma was a legitimate medical patient or a source of more amorous interest for Freud, as a recent movie suggests, Freud continued to treat Emma for three years.

24. Dr. William Beaumont and the Stomach

Image Source In 1822, a fur trader on Mackinac Island in Michigan was accidentally shot in the stomach and treated by Dr. William Beaumont. Despite dire predictions, the fur trader survived — but with a hole (fistula) in his stomach that never healed. Recognizing the unique opportunity to observe the digestive process, Beaumont began conducting experiments. Beaumont would tie food to a string, then insert it through the hole in the trader’s stomach. Every few hours, Beaumont would remove the food to observe how it had been digested. Though gruesome, Beaumont’s experiments led to the worldwide acceptance that digestion was a chemical, not a mechanical, process.

23. Electroshock Therapy on Children

Image Source In the 1960s, Dr. Lauretta Bender of New York’s Creedmoor Hospital began what she believed to be a revolutionary treatment for children with social issues — electroshock therapy. Bender’s methods included interviewing and analyzing a sensitive child in front of a large group, then applying a gentle amount of pressure to the child’s head. Supposedly, any child who moved with the pressure was showing early signs of schizophrenia. Herself the victim of a misunderstood childhood, Bender was said to be unsympathetic to the children in her care. By the time her treatments were shut down, Bender had used electroshock therapy on over 100 children, the youngest of whom was age three.

22. Project Artichoke

Image Source In the 1950s, the CIA’s Office of Scientific Intelligence ran a series of mind control projects in an attempt to answer the question “Can we get control of an individual to the point where he will do our bidding against his will and even against fundamental laws of nature?” One of these programs, Project Artichoke, studied hypnosis, forced morphine addiction, drug withdrawal, and the use of chemicals to incite amnesia in unwitting human subjects. Though the project was eventually shut down in the mid-1960s, the project opened the door to extensive research on the use of mind-control in field operations.

21. Hepatitis in Mentally Disabled Children

Image Source In the 1950s, Willowbrook State School, a New York state-run institution for mentally handicapped children, began experiencing outbreaks of hepatitis. Due to unsanitary conditions, it was virtually inevitable that these children would contract hepatitis. Dr. Saul Krugman, sent to investigate the outbreak, proposed an experiment that would assist in developing a vaccine. However, the experiment required deliberately infecting children with the disease. Though Krugman’s study was controversial from the start, critics were eventually silenced by the permission letters obtained from each child’s parents. In reality, offering one’s child to the experiment was oftentimes the only way to guarantee admittance into the overcrowded institution.

20. Operation Midnight Climax

Image Source Initially established in the 1950s as a sub-project of a CIA-sponsored, mind-control research program, Operation Midnight Climax sought to study the effects of LSD on individuals. In San Francisco and New York, unconsenting subjects were lured to safehouses by prostitutes on the CIA payroll, unknowingly given LSD and other mind-altering substances, and monitored from behind one-way glass. Though the safehouses were shut down in 1965, when it was discovered that the CIA was administering LSD to human subjects, Operation Midnight Climax was a theater for extensive research on sexual blackmail, surveillance technology, and the use of mind-altering drugs on field operations.

19. Study of Humans Accidentally Exposed to Fallout Radiation

Image Source The 1954 “Study of Response of Human Beings exposed to Significant Beta and Gamma Radiation due to Fall-out from High-Yield Weapons,” known better as Project 4.1, was a medical study conducted by the U.S. of residents of the Marshall Islands. When the Castle Bravo nuclear test resulted in a yield larger than originally expected, the government instituted a top secret study to “evaluate the severity of radiation injury” to those accidentally exposed. Though most sources agree the exposure was unintentional, many Marshallese believed Project 4.1 was planned before the Castle Bravo test. In all, 239 Marshallese were exposed to significant levels of radiation.

18. The Monster Study

Image Source In 1939, University of Iowa researchers Wendell Johnson and Mary Tudor conducted a stuttering experiment on 22 orphan children in Davenport, Iowa. The children were separated into two groups, the first of which received positive speech therapy where children were praised for speech fluency. In the second group, children received negative speech therapy and were belittled for every speech imperfection. Normal-speaking children in the second group developed speech problems which they then retained for the rest of their lives. Terrified by the news of human experiments conducted by the Nazis, Johnson and Tudor never published the results of their “Monster Study.”

17. Project MKUltra

Image Source Project MKUltra is the code name of a CIA-sponsored research operation that experimented in human behavioral engineering. From 1953 to 1973, the program employed various methodologies to manipulate the mental states of American and Canadian citizens. These unwitting human test subjects were plied with LSD and other mind-altering drugs, hypnosis, sensory deprivation, isolation, verbal and sexual abuse, and various forms of torture. Research occurred at universities, hospitals, prisons, and pharmaceutical companies. Though the project sought to develop “chemical […] materials capable of employment in clandestine operations,” Project MKUltra was ended by a Congress-commissioned investigation into CIA activities within the U.S.

16. Experiments on Newborns

Image Source In the 1960s, researchers at the University of California began an experiment to study changes in blood pressure and blood flow. The researchers used 113 newborns ranging in age from one hour to three days old as test subjects. In one experiment, a catheter was inserted through the umbilical arteries and into the aorta. The newborn’s feet were then immersed in ice water for the purpose of testing aortic pressure. In another experiment, up to 50 newborns were individually strapped onto a circumcision board, then tilted so that their blood rushed to their head and their blood pressure could be monitored.

15. The Aversion Project

Image Source In 1969, during South Africa’s detestable Apartheid era, thousands of homosexuals were handed over to the care of Dr. Aubrey Levin, an army colonel and psychologist convinced he could “cure” homosexuals. At the Voortrekkerhoogte military hospital near Pretoria, Levin used electroconvulsive aversion therapy to “reorientate” his patients. Electrodes were strapped to a patient’s upper arm with wires running to a dial calibrated from 1 to 10. Homosexual men were shown pictures of a naked man and encouraged to fantasize, at which point the patient was subjected to severe shocks. When Levin was warned that he would be named an abuser of human rights, he emigrated to Canada where he currently works at a teaching hospital.

14. Medical Experiments on Prison Inmates

Image Source Perhaps one benefit of being an inmate at California’s San Quentin prison is the easy access to acclaimed Bay Area doctors. But if that’s the case, then a downside is that these doctors also have easy access to inmates. From 1913 to 1951, Dr. Leo Stanley, chief surgeon at San Quentin, used prisoners as test subjects in a variety of bizarre medical experiments. Stanley’s experiments included sterilization and potential treatments for the Spanish Flu. In one particularly disturbing experiment, Stanley performed testicle transplants on living prisoners using testicles from executed prisoners and, in some cases, from goats and boars.

13. Sexual Reassignment

Image Source In 1965, Canadian David Peter Reimer was born biologically male. But at seven months old, his penis was accidentally destroyed during an unconventional circumcision by cauterization. John Money, a psychologist and proponent of the idea that gender is learned, convinced the Reimers that their son would be more likely to achieve a successful, functional sexual maturation as a girl. Though Money continued to report only success over the years, David’s own account insisted that he had never identified as female. He spent his childhood teased, ostracized, and seriously depressed. At age 38, David committed suicide by shooting himself in the head.

12. Effect of Radiation on Testicles

Image Source Between 1963 and 1973, dozens of Washington and Oregon prison inmates were used as test subjects in an experiment designed to test the effects of radiation on testicles. Bribed with cash and the suggestion of parole, 130 inmates willingly agreed to participate in the experiments conducted by the University of Washington on behalf of the U.S. government. In most cases, subjects were zapped with over 400 rads of radiation (the equivalent of 2,400 chest x-rays) in 10 minute intervals. However, it was much later that the inmates learned the experiments were far more dangerous than they had been told. In 2000, the former participants settled a $2.4 million class-action settlement from the University.

11. Stanford Prison Experiment

Image Source Conducted at Stanford University from August 14-20, 1971, the Stanford Prison Experiment was an investigation into the causes of conflict between military guards and prisoners. Twenty-four male students were chosen and randomly assigned roles of prisoners and guards. They were then situated in a specially-designed mock prison in the basement of the Stanford psychology building. Those subjects assigned to be guards enforced authoritarian measures and subjected the prisoners to psychological torture. Surprisingly, many of the prisoners accepted the abuses. Though the experiment exceeded the expectations of all of the researchers, it was abruptly ended after only six days.

10. Syphilis Experiments in Guatemala

Image Source From 1946 to 1948, the United States government, Guatemalan president Juan José Arévalo, and some Guatemalan health ministries, cooperated in a disturbing human experiment on unwitting Guatemalan citizens. Doctors deliberately infected soldiers, prostitutes, prisoners, and mental patients with syphilis and other sexually transmitted diseases in an attempt to track their untreated natural progression. Treated only with antibiotics, the experiment resulted in at least 30 documented deaths. In 2010, the United States made a formal apology to Guatemala for their involvement in these experiments.

9. Tuskegee Syphilis Study

Image Source In 1932, the U.S. Public Health Service began working with the Tuskegee Institute to track the natural progression of untreated syphilis. Six hundred poor, illiterate, male sharecroppers were found and hired in Macon County, Alabama. Of the 600 men, only 399 had previously contracted syphilis, and none were told they had a life threatening disease. Instead, they were told they were receiving free healthcare, meals, and burial insurance in exchange for participating. Even after Penicillin was proven an effective cure for syphilis in 1947, the study continued until 1972. In addition to the original subjects, victims of the study included wives who contracted the disease, and children born with congenital syphilis. In 1997, President Bill Clinton formally apologized to those affected by what is often called the “most infamous biomedical experiment in U.S. history.”

8. Milgram Experiment

In 1961, Stanley Milgram, a psychologist at Yale University, began a series of social psychology experiments that measured the willingness of test subjects to obey an authority figure. Conducted only three months after the start of the trial of German Nazi war criminal Adolf Eichmann, Milgram’s experiment sought to answer the question, “Could it be that Eichmann and his million accomplices in the Holocaust were just following orders?” In the experiment, two participants (one secretly an actor and one an unwitting test subject) were separated into two rooms where they could hear, but not see, each other. The test subject would then read a series of questions to the actor, punishing each wrong answer with an electric shock. Though many people would indicate their desire to stop the experiment, almost all subjects continued when they were told they would not be held responsible, or that there would not be any permanent damage.

7. Infected Mosquitos in Towns

In 1956 and 1957, the United States Army conducted a number of biological warfare experiments on the cities of Savannah, Georgia and Avon Park, Florida. In one such experiment, millions of infected mosquitos were released into the two cities, in order to see if the insects could spread yellow fever and dengue fever. Not surprisingly, hundreds of researchers contracted illnesses that included fevers, respiratory problems, stillbirths, encephalitis, and typhoid. In order to photograph the results of their experiments, Army researchers pretended to be public health workers. Several people died as a result of the research.

6. Human Experimentation in the Soviet Union

Beginning in 1921 and continuing for most of the 21st century, the Soviet Union employed poison laboratories known as Laboratory 1, Laboratory 12, and Kamera as covert research facilities of the secret police agencies. Prisoners from the Gulags were exposed to a number of deadly poisons, the purpose of which was to find a tasteless, odorless chemical that could not be detected post mortem. Tested poisons included mustard gas, ricin, digitoxin, and curare, among others. Men and women of varying ages and physical conditions were brought to the laboratories and given the poisons as “medication,” or part of a meal or drink.

5. Human Experimentation in North Korea

Image Source Several North Korean defectors have described witnessing disturbing cases of human experimentation. In one alleged experiment, 50 healthy women prisoners were given poisoned cabbage leaves — all 50 women were dead within 20 minutes. Other described experiments include the practice of surgery on prisoners without anesthesia, purposeful starvation, beating prisoners over the head before using the zombie-like victims for target practice, and chambers in which whole families are murdered with suffocation gas. It is said that each month, a black van known as “the crow” collects 40-50 people from a camp and takes them to an known location for experiments.

4. Nazi Human Experimentation

Image Source Over the course of the Third Reich and the Holocaust, Nazi Germany conducted a series of medical experiments on Jews, POWs, Romani, and other persecuted groups. The experiments were conducted in concentration camps, and in most cases resulted in death, disfigurement, or permanent disability. Especially disturbing experiments included attempts to genetically manipulate twins; bone, muscle, and nerve transplantation; exposure to diseases and chemical gasses; sterilization, and anything else the infamous Nazi doctors could think up. After the war, these crimes were tried as part of the Nuremberg Trial and ultimately led to the development of the Nuremberg Code of medical ethics.

3. Unit 731

Image Source From 1937 to 1945, the imperial Japanese Army developed a covert biological and chemical warfare research experiment called Unit 731. Based in the large city of Harbin, Unit 731 was responsible for some of the most atrocious war crimes in history. Chinese and Russian subjects — men, women, children, infants, the elderly, and pregnant women — were subjected to experiments which included the removal of organs from a live body, amputation for the study of blood loss, germ warfare attacks, and weapons testing. Some prisoners even had their stomachs surgically removed and their esophagus reattached to the intestines. Many of the scientists involved in Unit 731 rose to prominent careers in politics, academia, business, and medicine.

2. Radioactive Materials in Pregnant Women

Image Source Shortly after World War II, with the impending Cold War forefront on the minds of Americans, many medical researchers were preoccupied with the idea of radioactivity and chemical warfare. In an experiment at Vanderbilt University, 829 pregnant women were given “vitamin drinks” they were told would improve the health of their unborn babies. Instead, the drinks contained radioactive iron and the researchers were studying how quickly the radioisotope crossed into the placenta. At least seven of the babies later died from cancers and leukemia, and the women themselves experienced rashes, bruises, anemia, loss of hair and tooth, and cancer.

1. Mustard Gas Tested on American Military

Image Source In 1943, the U.S. Navy exposed its own sailors to mustard gas. Officially, the Navy was testing the effectiveness of new clothing and gas masks against the deadly gas that had proven so terrifying in the first World War. The worst of the experiments occurred at the Naval Research Laboratory in Washington. Seventeen and 18-year old boys were approached after eight weeks of boot camp and asked if they wanted to participate in an experiment that would help shorten the war. Only when the boys reached the Research Laboratory were they told the experiment involved mustard gas. The participants, almost all of whom suffered severe external and internal burns, were ignored by the Navy and, in some cases, threatened with the Espionage Act. In 1991, the reports were finally declassified and taken before Congress.

28. Prison Inmates as Test Subjects Henrietta Lacks 26. Project QKHILLTOP 25. Stateville Penitentiary Malaria Study Stateville Penitentiary Malaria Study: Primaquine 24. Emma Eckstein 23. Dr. William Beaumont Dr. William Beaumont 21. Electroshock Therapy on Children 21. Project Artichoke 20. Operation Midnight Climax 19. Study of Humans Accidentally Exposed to Fallout Radiation 18. The Monster Experiment 17. Project MKUltra 16. Experiments on Newborns 15. The Aversion Project 14. Medical Experiments on Prison Inmates 13. Sexual Reassignment 12. Effect of Radiation on Testicles 11. Stanford Prison Experiment 10. Syphilis Experiment in Guatemala 9. Tuskegee Syphilis Study 8. Milgram Experiment 7. Infected Mosquitos in Towns 6. Human Experimentation in the Soviet Union 5. Human Experimentation in North Korea 4. Nazi Human Experimentation 3. Unit 731 2. Radioactive Materials in Pregnant Women 1. Mustard Gas Tested on American Military

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Unethical Psychological Experiments: Dark Chapters in the History of Science

Throughout history, the pursuit of scientific knowledge has sometimes led researchers down dark paths, where the lines between ethical and unethical practices have been blurred or even completely disregarded. The field of psychology, with its focus on understanding human behavior and cognition, has not been immune to these ethical transgressions. In fact, some of the most notorious and controversial experiments in scientific history have emerged from psychological research.

When we talk about unethical experiments in psychology, we’re referring to studies that violate fundamental ethical principles. These principles include respect for human dignity, informed consent, and the protection of participants from harm. Such experiments often prioritize scientific discovery over the well-being of their subjects, leading to lasting psychological and sometimes physical damage.

The history of ethical guidelines in psychological research is relatively recent. It wasn’t until the mid-20th century that formal ethical codes began to emerge in response to egregious violations of human rights in the name of science. The Nuremberg Code of 1947, established after the horrific Nazi experiments during World War II, was one of the first attempts to codify ethical standards for human research. However, it took several more decades and numerous controversial studies for the field of psychology to fully embrace comprehensive ethical guidelines.

Understanding past unethical practices in psychology is crucial for several reasons. First, it serves as a stark reminder of the potential for harm when scientific curiosity is unchecked by moral considerations. Second, it helps us appreciate the importance of current ethical standards and the need for continued vigilance. Finally, examining these dark chapters in scientific history can provide valuable insights into human nature and the complex dynamics of power and obedience.

The Stanford Prison Experiment: A Descent into Darkness

One of the most infamous psychological experiments of all time is the Stanford Prison Experiment, conducted by Philip Zimbardo in 1971. The study aimed to investigate the psychological effects of perceived power in a simulated prison environment. Zimbardo recruited 24 male college students and randomly assigned them roles as either prisoners or guards in a mock prison set up in the basement of Stanford University.

The experiment was initially planned to last two weeks but was terminated after just six days due to the alarming behavior that emerged. The “guards” quickly began to abuse their power, subjecting the “prisoners” to increasingly cruel and degrading treatment. Meanwhile, the “prisoners” showed signs of severe emotional distress, with some even experiencing nervous breakdowns.

The ethical concerns raised by the Stanford Prison Experiment are numerous and profound. Participants were not fully informed about the nature of the study or the potential psychological risks involved. The lack of proper oversight allowed the situation to spiral out of control, with Zimbardo himself becoming too deeply involved as the “prison superintendent.” Perhaps most disturbingly, the experiment continued even after it became clear that participants were suffering significant psychological harm.

The long-term impact of the Stanford Prison Experiment on its participants has been a subject of ongoing debate. Some reported lasting trauma and nightmares, while others claimed the experience was ultimately positive, leading to personal growth and self-reflection. Regardless of individual outcomes, the study has had a profound influence on psychological research and our understanding of situational influences on human behavior.

The Milgram Obedience Experiment: Testing the Limits of Authority

Another landmark study that pushed ethical boundaries was the Milgram Obedience Experiment , conducted by Stanley Milgram in the early 1960s. Inspired by the Holocaust and the defense of Nazi war criminals that they were “just following orders,” Milgram sought to investigate the extent to which ordinary people would obey authority figures, even when asked to perform morally questionable acts.

The experimental design was deceptively simple yet deeply unsettling. Participants were told they were taking part in a study on learning and memory. They were instructed to administer electric shocks to a “learner” (actually an actor) whenever the learner gave incorrect answers to a series of questions. The voltage of the shocks increased with each wrong answer, eventually reaching levels marked as dangerous and even potentially fatal.

The results were shocking, both figuratively and literally. A staggering 65% of participants continued to administer shocks up to the maximum voltage, despite hearing the learner’s increasingly distressed cries and pleas to stop. Milgram’s findings suggested that ordinary people could be compelled to act against their moral judgments when pressured by authority figures.

The ethical issues raised by Milgram’s study were numerous. Participants were deceived about the true nature of the experiment and subjected to severe psychological stress. Many experienced intense anxiety and guilt, believing they had seriously harmed or even killed another person. The study also raised questions about the long-term psychological effects on participants who discovered they were capable of such obedience to authority.

Despite these ethical concerns, the Milgram Obedience Experiment has had a profound influence on our understanding of authority, obedience, and moral decision-making. It has been widely cited in discussions of historical atrocities and continues to inform debates about personal responsibility in hierarchical systems.

The Little Albert Experiment: Fear and Ethics in Infant Research

Moving back in time to the early days of behaviorism, we encounter the Little Albert Experiment , conducted by John B. Watson and Rosalie Rayner in 1920. This controversial study aimed to demonstrate that emotional reactions could be classically conditioned in humans, using a 9-month-old infant known as “Little Albert” as the subject.

Watson and Rayner began by presenting Little Albert with various stimuli, including a white rat, a rabbit, a monkey, masks, and burning newspapers. Initially, Albert showed no fear of these objects. The researchers then paired the presentation of the rat with a loud, frightening noise. After several such pairings, Albert began to cry and show fear when the rat was presented alone. This fear response then generalized to other similar objects, such as a rabbit and a dog.

The ethical violations in this study are glaring by modern standards. Experimenting on an infant who could not provide consent, deliberately causing fear and distress, and potentially creating long-lasting phobias are all clear breaches of ethical research practices. Moreover, there was no attempt to decondition Little Albert’s fear response at the end of the study.

The long-term consequences for Little Albert have been a subject of much speculation and investigation. Some researchers have attempted to identify the real identity of Little Albert and trace his life after the experiment. While these efforts have yielded conflicting results, they highlight the enduring ethical debates surrounding this infamous study.

The Monster Study: When Research Becomes Monstrous

Perhaps one of the most egregious examples of unethical psychological research is The Monster Study , conducted by Dr. Wendell Johnson and his team at the University of Iowa in 1939. This experiment, which remained hidden from public knowledge for decades, aimed to investigate the effect of negative speech therapy on children’s fluency.

The study involved 22 orphaned children, half of whom were placed in a control group and received positive speech therapy. The other half, however, were subjected to constant criticism of their speech, being told they were beginning to stutter even when they spoke normally. The researchers hypothesized that this negative reinforcement would lead to the development of stuttering in children who previously had no speech problems.

The ethical breaches in this study are numerous and severe. Experimenting on vulnerable orphaned children, deliberately attempting to induce a speech disorder, and potentially causing lasting psychological harm are all clear violations of ethical research standards. The fact that the study was kept secret for so long only adds to its troubling nature.

The lasting effects on the participants were profound. Many of the children in the negative reinforcement group developed lasting speech problems and suffered from low self-esteem and other psychological issues well into adulthood. When the study finally came to light in 2001, it sparked public outrage and led to a lawsuit against the state of Iowa, which was eventually settled for $925,000.

Modern Ethical Guidelines in Psychological Research

The dark history of unethical psychological experiments has played a crucial role in the development of modern ethical standards in research. Organizations like the American Psychological Association (APA) have established comprehensive ethical guidelines that all researchers must follow. These guidelines are regularly updated to address new ethical challenges that arise with advances in research methods and technology.

Key principles of ethical psychological research now include:

1. Informed consent: Participants must be fully informed about the nature of the study and any potential risks before agreeing to participate.

2. Minimization of harm: Researchers must take all possible steps to protect participants from physical or psychological harm.

3. Right to withdraw: Participants must be informed that they can leave the study at any time without penalty.

4. Confidentiality: Researchers must protect the privacy and personal information of participants.

5. Debriefing: After the study, participants must be fully informed about the true nature of the research and any deception used.

One of the most important safeguards against unethical research practices is the Institutional Review Board (IRB) . These committees, composed of experts in various fields, review research proposals to ensure they meet ethical standards before allowing them to proceed. IRBs play a crucial role in preventing unethical studies and protecting the rights and well-being of research participants.

The Belmont Report , published in 1979, has been particularly influential in shaping ethical guidelines for human research. It outlines three fundamental principles: respect for persons, beneficence, and justice. These principles continue to guide ethical decision-making in psychological research today.

As we reflect on the dark chapters of psychological research history, several important lessons emerge. First and foremost, we are reminded of the paramount importance of ethical considerations in scientific inquiry. The pursuit of knowledge, no matter how potentially valuable, can never justify the violation of human rights or the infliction of lasting harm on research participants.

Secondly, these unethical experiments highlight the power dynamics inherent in research settings and the potential for abuse when proper safeguards are not in place. The banality of evil , a concept often associated with these studies, reminds us that ordinary people can commit harmful acts when placed in positions of authority or when following orders.

Finally, these studies underscore the complexity of human behavior and the sometimes unexpected outcomes of psychological manipulation. While the methods used in these experiments were deeply unethical, the insights gained have contributed to our understanding of human psychology and have informed practices in fields ranging from education to law enforcement.

In contemporary research, balancing scientific progress with participant well-being and rights remains an ongoing challenge. As new technologies emerge, such as brain imaging and genetic testing, novel ethical dilemmas arise. Researchers must continually reassess and update ethical guidelines to address these new challenges.

It’s worth noting that not all controversial psychological studies are necessarily unethical. Some studies that push ethical boundaries may be justified if they have significant potential benefits and incorporate robust safeguards to protect participants. The key is to carefully weigh the potential risks against the expected benefits and to always prioritize the well-being of research participants.

In conclusion, the history of unethical psychological experiments serves as a sobering reminder of the potential for harm when scientific curiosity is unchecked by moral considerations. It underscores the critical importance of ethical guidelines and oversight in research. As we continue to push the boundaries of psychological knowledge, we must remain vigilant in our commitment to ethical practices, ensuring that the pursuit of scientific understanding never comes at the cost of human dignity and well-being.

By learning from these dark chapters in our scientific history, we can strive to conduct research that not only advances our understanding of the human mind but also respects and protects the individuals who make that research possible. After all, true scientific progress is not just about what we discover, but how we discover it.

References:

1. Zimbardo, P. G. (1973). On the ethics of intervention in human psychological research: With special reference to the Stanford Prison Experiment. Cognition, 2(2), 243-256.

2. Milgram, S. (1963). Behavioral study of obedience. The Journal of Abnormal and Social Psychology, 67(4), 371-378.

3. Watson, J. B., & Rayner, R. (1920). Conditioned emotional reactions. Journal of Experimental Psychology, 3(1), 1-14.

4. Ambrose, N. G., & Yairi, E. (2002). The Tudor study: Data and ethics. American Journal of Speech-Language Pathology, 11(2), 190-203.

5. American Psychological Association. (2017). Ethical principles of psychologists and code of conduct. https://www.apa.org/ethics/code

6. National Commission for the Protection of Human Subjects of Biomedical and Behavioral Research. (1979). The Belmont Report: Ethical principles and guidelines for the protection of human subjects of research. https://www.hhs.gov/ohrp/regulations-and-policy/belmont-report/index.html

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Controversial and Unethical Psychology Experiments

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

Shereen Lehman, MS, is a healthcare journalist and fact checker. She has co-authored two books for the popular Dummies Series (as Shereen Jegtvig).

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."

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10 Psychological Experiments That Went Way Too Far

What is and isn’t regarded as ethical is a complicated and heated topic for debate. One area, in particular, is whether it is ethical to harm someone to help others. Many will draw a hard line in the sand and state that it is never justifiable. Others might have certain tolerances, such as, if one can significantly help a large enough group of people, then some amount of isolated harm may be acceptable.

Scientific experiments can often find themselves at the heart of these debates. A key breakthrough could save the lives of millions for generations to come, yet every experiment needs a subject. With this in mind, let’s take a look at 10 of the most controversial psychological experiments of all time. All have been heavily criticized for overstepping ethical boundaries, and many of them have been accused of being outright sadistic.

The Milgram Experiment

In Stanley Milgram ‘s infamous experiment, participants were asked to administer an electric shock to a learner each time they got an answer wrong. They then had to increase the voltage before asking another question. While the participants thought they were part of a study exploring learning methods, they were actually the subjects of another experiment. Some participants were actors ― and the shocks were not really administered. The real study explored how much someone would be willing to cause pain to another as a result of being told to do so by an authority figure. The study showed that the majority of participants administered the maximum level of what they believed to be 450 volts, despite the “earners” crying out in pain. While the actors actually didn’t receive any real harm, the participants who administered the electric shocks were under severe stress during the experiment and were deeply affected long afterwards.

The Stanford Prison Experiment

In 1971, Professor Philip Zimbardo, a professor emeritus at Stanford University, enlisted 24 male volunteers to explore the psychology of prisoner ill-treatment. The participants were split into two groups, prisoners and guards. Zimbardo, playing the role of superintendent, created a convincing simulated prison, complete with barred doors, prison cells and guards. Those assigned the role of prisoner were arrested at their homes and taken to the local police station. They were then fingerprinted and photographed before being blindfolded and dropped off at the “prison.” Once there, the prisoners were stripped of their personal items and dressed in prison clothes. Some of the guards were strongly affected by their role and within hours, abuse began. The guards verbally harassed the prisoners with insults, woke them up with whistles and forced them to complete pointless tasks. They sprayed them with a fire extinguisher and forced them to strip naked. The guards also removed the prisoners’ beds, therefore forcing them to sleep on the concrete floor. After five days, Zimbardo had to prematurely end the experiment. Although it didn’t even last a week, many of the prisoners suffered intense emotional trauma.

The experiment inspired a movie, a book ― “ The Lucifer Effect: Understanding How Good People Turn Evil ” ― and a documentary.

The Bobo Doll Experiment

In the early 1960s, Professor Albert Bandura, a professor emeritus at Stanford University, often called one of the most influential psychologists of the 20 th century, conducted a study to explore if violent behavior could be learned through observation. In his experiment, nursery-aged children watched an adult physically and verbally attack an inflatable doll. Bandura then observed how the children would treat the doll when left alone without supervision. Shockingly, the children quickly adopted the observed behavior and attacked the doll both verbally and physically with great intensity, even hitting it with a mallet. The experiment came under scrutiny as the children were essentially trained to become angry and attack without reason. What’s more, the experimenters were unsure of the potential long-term implications.

The Little Albert Experiment

In 1920, renowned behaviorist John Watson carried out an experiment exploring if a baby could be conditioned to experience illogical fear . In the experiment , eight-month-old Albert was introduced to a white rat and it was observed that he showed no sign of fear. In an attempt to make little Albert fear the rat, Watson would repeatedly reintroduce it while creating a loud, sudden noise at the same time (aggressively banging an iron rod). Once Watson had thoroughly anchored the association, little Albert would burst into floods of tears at even a brief sighting of the rat, with or without the addition of the loud noise. It didn’t stop there. Watson also proved his hypothesis by successfully transferring the learned fear by rendering Albert afraid of rabbits, dogs and even Father Christmas. Watson never revealed who Albert was before his death, but researchers tracked down several different candidates, including one who had despised dogs.

The Monkey Drug Trials

While it might seem that humans can get the short end of the stick in the name of science, it’s nothing compared to the treatment of other animals. In the late 1960s, researchers at the University of Michigan carried out a series of studies exploring illegal substance addiction. As part of the experiment , they injected primates with large quantities of various drugs. They then observed if the monkeys would eventually freely administer the drugs themselves. Many of the monkeys developed strong addictions and administered the drugs until they died. The study continues to receive criticism as it is unsure how much the results could relate to human behavior, particularly as the monkeys were taken out of their natural habitat and kept in a confined and foreign environment.

The Pit of Despair

Psychologist Harry Harlow wanted to explore the relationship between maternal-separation and clinical depression. In his experiment at the University of Wisconsin-Madison, he separated baby monkeys from their mothers and kept them in small, isolated chambers. The baby monkeys quickly became severely depressed. They stopped playing, stopped communicating, and in some cases, starved themselves to death. The experiment received a lot of criticism with regards to ethics, especially as it was well understood that baby monkeys develop incredibly strong bonds with their mothers and stay with them much longer than most mammals. Not only was the experiment viewed as inhumane, but to many the conclusion of depression was also widely viewed as inevitable. It did, however, prove the importance of mother-child bonding and interaction.

“Curing” Homosexuality

Looking back through history we can find many attitudes, perceptions and beliefs that the vast majority of us would be disgusted by today. One particularly cruel yet common belief was that homosexuality was unnatural and that it ought to be cured. Many attempted to develop treatments, some of which were well-documented, including one that was published in the British Medical Journal. In the late 1960s, researchers in England tried to “treat” a group of homosexual men. In the experiment, the men were shown suggestive pictures of both men and women. When images of women were displayed, the participants were encouraged to look freely without punishment. However, when images of men were displayed, the participants were administered an electric shock.

Unsolicited Gender Reassignment

Harvard-educated psychologist Dr. John Money , who worked at Johns Hopkins University, is known for defining the concepts of gender role and identity. In the mid-‘60s, after infant David Reimer’s penis was badly maimed during circumcision, Money convinced Reimer’s parents that the child should undergo sex reassignment surgery and be raised as a female. This stemmed from Money’s belief that gender was learned socially. Although Money reported that the reassignment was nothing but a huge success, Reimer stated otherwise. Reimer said he was never able to identify as a female and began living as a male. He suffered from extreme depression, which eventually led him to commit suicide at age 38.

The Schizophrenia Medication Experiment

In the early ‘80s, scientists from UCLA began to study schizophrenia. In particular, they explored why people might relapse back to the disorder. To find suitable patients they took those who previously had schizophrenia off their medication. Their experiment was criticized for a number of reasons, including their lack of attention to the safety of the participants involved. A tragic example was the suicide of Tony Lamadrid , who jumped off a building after being taken off his medication.

The Monster Study

In the late ‘30s, University of Iowa Professor Wendell Johnson and his master’s student, Mary Tudor, explored whether speech difficulties could be improved depending on what children were told. However, they also explored the reverse, wanting to see if they could create speech difficulties. To achieve this, they lied to children with healthy speech by telling them that they were developing speech problems. After giving children this false diagnosis, they told them that they must correct their “poor” speech and refrain from speaking unless they felt they could do it correctly. While the scientists were largely unable to improve speech, they were highly successful at negatively impacting healthy speech. Those who were told that they were developing speech problems became very self-conscious, spoke far less often and grew incredibly frustrated. Some became fearful of certain letters and words while others completely refused to speak. Others also developed behavioral tics such as snapping their fingers, covering their eyes with their hands and shuffling their feet. Many of them suffered lifelong psychological damage as their symptoms were unable to be reversed.

Can We Learn From These Events?

While we may not agree with the methods used in the aforementioned studies, they still provide valuable insight into the psychological consequences of extreme situations. While they demonstrate some of the worst capabilities of the human mind, they also highlight the importance of how we should treat others. It is also important to consider the era in which these experiments were created, for they not only reflect the mindset of the scientists but the perceptions of the time. Therefore, while we may judge the decisions of those before us, it is wise to reflect upon how future generations will critique our actions. Are there perspectives today that we assume are harmless that might one day be considered grossly unethical?

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About the author.

Chris Macdonald

Chris Macdonald is a scientist and author. His latest book, Operation Sustainable Human, is now available on Amazon. To keep up to date with Chris’s latest projects, you can follow him on Instagram: @ChrisMacdonaldOfficial

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The 10 Cruelest Human Experimentation Cases in History

Dr. Shiro Ishii and Unit 731

“The Little Albert Experiment”

The “Monster” Study

The Stanford Prison Experiment

The South African ‘Aversion Project’

Project 4.1

The Tuskegee Experiments

Project MK-Ultra

Guatemalan Syphilis Experiment

Mengele’s Twins

10 Outrageous Experiments Conducted on Humans

10: Tuskegee Syphilis Study

9: The Nazi Medical Experiments

8: Watson's 'Little Albert' Experiment

7: The Monster Study of 1939

6: Stateville Penitentiary Malaria Study

5: The Aversion Project in South Africa

4: Milgram Shock Experiments

3: CIA Mind-Control Experiments (Project MK-Ultra)

2: Unit 731

1: The Human Vivisections of Herophilus

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Milgram Experiment

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Little Albert

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30. The Tearoom Sex Study

29. Prison Inmates as Test Subjects

28. Henrietta Lacks

27. Project QKHILLTOP

26. Stateville Penitentiary Malaria Study

25. Emma Eckstein and Sigmund Freud

24. Dr. William Beaumont and the Stomach

23. Electroshock Therapy on Children

22. Project Artichoke

21. Hepatitis in Mentally Disabled Children

20. Operation Midnight Climax

19. Study of Humans Accidentally Exposed to Fallout Radiation

18. The Monster Study

17. Project MKUltra

16. Experiments on Newborns

15. The Aversion Project

14. Medical Experiments on Prison Inmates

13. Sexual Reassignment

12. Effect of Radiation on Testicles

11. Stanford Prison Experiment

10. Syphilis Experiments in Guatemala

9. Tuskegee Syphilis Study

8. Milgram Experiment

7. Infected Mosquitos in Towns

6. Human Experimentation in the Soviet Union

5. Human Experimentation in North Korea

4. Nazi Human Experimentation

3. Unit 731

2. Radioactive Materials in Pregnant Women

1. Mustard Gas Tested on American Military

Unethical Psychological Experiments: Dark Chapters in the History of Science

The Stanford Prison Experiment: A Descent into Darkness

The Milgram Obedience Experiment: Testing the Limits of Authority

The Little Albert Experiment: Fear and Ethics in Infant Research