10 Psychological Experiments That Ended Horribly Wrong

Psychology is both an applied and academic field that studies the human mind and behavior. Research in psychology seeks to understand and explain how we think, act and feel. Applications for psychology include mental health treatment, performance enhancement, self-help, ergonomics and many other areas affecting health and daily life.

Many psychological experiments have been valid and ethical, allowing researchers to make new treatments and therapies available, and giving other insights into our motivations and actions. Sadly, others have ended up backfiring horribly — ruining lives and shaming the profession.  Though these are highly unethical experiments, it should be mentioned that they did pave the way to induct our current ethical standards of experiments, and that should be seen as a positive. Here are ten psychological experiments that spiraled out of control.

10. Stanford Prison Experiment

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

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

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

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

9. The Monster Study

In this study, conducted in 1939, 22 orphaned children, 10 with stutters, were separated equally into two groups: one with a speech therapist who conducted “positive” therapy by praising the children’s progress and fluency of speech; the other with a speech therapist who openly chastised the children for the slightest mistake. The results showed that the children who had received negative responses were badly affected in terms of their psychological health. Yet more bad news was to come as it was later revealed that some of the children who had previously been unaffected developed speech problems following the experiment. In 2007, six of the orphan children were awarded $925,000 in compensation for emotional damage that the six-month-study had left them with.


The CIA performed many unethical experiments into mind control and psychology under the banner of project MK-ULTRA during the 50s and 60s. Theodore Kaczynski, otherwise known as the Unabomber, is reported to have been a test subject in the CIA’s disturbing experiments, which may have contributed to his mental instability. In another case, the administration of LSD to US Army biological weapons expert Frank Olson is thought to have sparked a crisis of conscience, inspiring him to tell the world about his research. Instead, Olson is said to have committed suicide, jumping from a thirteenth-story hotel room window, although there is strong evidence that he was murdered. This doesn’t even touch on the long-term psychological damage other test subjects are likely to have suffered.

7.  Monkey Drug Trials 1969

Lab Monkey

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

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

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

6. Milgram Experiment

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

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

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

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

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

5. Study on Schizophrenia at The University of California at Los Angeles

In the U.C.L.A. study, which began in 1983 and is still going on, 23 of 50 patients under treatment for schizophrenia suffered severe relapses after their medicine was stopped. Several of the patients had more than one severe relapse, including hallucinations and paranoia.

Researchers in the study, the U.C.L.A. schizophrenic disorders research project, say they are trying to find out if some schizophrenics might do better without medication.

All of the patients signed “informed consent” documents stating that they understood that in the experiment their conditions might “improve, worsen or remain unchanged.” But they were not told how severe their relapses might be — that they could suffer worsening symptoms with each recurrence, according to the Federal agency, the Office of Protection from Research Risks.

Families of two of the patients filed complaints about the experiment with the Federal Government. One patient, Antonio Lamadrid, a former U.C.L.A. student, committed suicide. The other, Gregory Aller, dropped out of college and threatened to kill his parents.

In its final report, the office on research risks, at the National Institutes of Health, said that the experiment had “failed to comply with the requirements of H.H.S. regulations” by not telling patients the extent of the risks they would be asked to take and not telling them that ordinary treatment would be safer for most of them. The report, which has not been released publicly, was obtained from a person involved in the inquiry.

4. Pit of Despair

The pit of despair was a name used by American comparative psychologist Harry Harlow for a device he designed, technically called a vertical chamber apparatus, that he used in experiments on rhesus macaque monkeys at the University of Wisconsin–Madison in the 1970s. Most of the monkeys placed inside it were at least three months old and had already bonded with others. The point of the experiment was to break those bonds in order to create the symptoms of depression. Harlow ignored the criticism of his colleagues, and is quoted as saying, “How could you love monkeys?” The last laugh was on him, however, as his horrific treatment of his subjects is acknowledged as being a driving force behind the development of the animal rights movement and the end of such cruel experiments.

3. The Third Wave

The Third Wave was an experiment to demonstrate that even democratic societies are not immune to the appeal of fascism. It was undertaken by history teacher Ron Jones with sophomore high school students attending his “Contemporary World” history class as part of a study of Nazi Germany. The experiment took place at Cubberley High School in Palo Alto, California, during the first week of April 1967.Jones, unable to explain to his students how the German population could claim ignorance of the extermination of the Jewish people, decided to show them instead. Jones started a movement called “The Third Wave” and told his students that the movement aimed to eliminate democracy. The idea that democracy emphasizes individuality was considered as a drawback of democracy, and Jones emphasized this main point of the movement in its motto: “Strength through discipline, strength through community, strength through action, strength through pride.”

The experiment took on a life of its own, with students from all over the school joining in: on the third day the class expanded from initial 30 students to 43 attendees. All of the students showed drastic improvement in their academic skills and tremendous motivation. All of the students were issued a member card and each of them received a special assignment (like designing a Third Wave Banner, stopping non-members from entering the class, etc.). Jones instructed the students on how to initiate new members, and by the end of the day the movement had over 200 participants. Jones was surprised that some of the students started reporting to him when other members of the movement failed to abide by the rules.

On Thursday, the fourth day of the experiment, Jones decided to terminate the movement because it was slipping out of his control. The students became increasingly involved in the project and their discipline and loyalty to the project was outstanding. He announced to the participants that this movement was a part of a nationwide movement and that on the next day a presidential candidate of the movement would publicly announce existence of the movement. Jones ordered students to attend a noon rally on Friday to witness the announcement.

Instead of a televised address of their leader, the students were presented with an empty channel. After a few minutes of waiting, Jones announced that they had been a part of an experiment in fascism and that they all willingly created a sense of superiority that German citizens had in the period of Nazi Germany. He then played them a film about the Nazi regime to conclude the experiment.

After the experiment ended, Jones was fired from the school.

2. Homosexual Aversion Therapy

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

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

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

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

1. David Reimer

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

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

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