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5 Unethical Medical Experiments Brought Out of the Shadows of History

Prisoners and other vulnerable populations often bore the brunt of unethical medical experimentation..

Most people are aware of some of the heinous medical experiments of the past that violated human rights. Participation in these studies was either forced or coerced under false pretenses. Some of the most notorious examples include the experiments by the Nazis, the Tuskegee syphilis study, the Stanford Prison Experiment, and the CIA’s LSD studies.

But there are many other lesser-known experiments on vulnerable populations that have flown under the radar. Study subjects often didn’t — or couldn’t — give consent. Sometimes they were lured into participating with a promise of improved health or a small amount of compensation. Other times, details about the experiment were disclosed but the extent of risks involved weren’t.

This perhaps isn’t surprising, as doctors who conducted these experiments were representative of prevailing attitudes at the time of their work. But unfortunately, even after informed consent was introduced in the 1950s , disregard for the rights of certain populations continued. Some of these researchers’ work did result in scientific advances — but they came at the expense of harmful and painful procedures on unknowing subjects.

Here are five medical experiments of the past that you probably haven’t heard about. They illustrate just how far the ethical and legal guidepost, which emphasizes respect for human dignity above all else, has moved.

The Prison Doctor Who Did Testicular Transplants

From 1913 to 1951, eugenicist Leo Stanley was the chief surgeon at San Quentin State Prison, California’s oldest correctional institution. After performing vasectomies on prisoners, whom he recruited through promises of improved health and vigor, Stanley turned his attention to the emerging field of endocrinology, which involves the study of certain glands and the hormones they regulate. He believed the effects of aging and decreased hormones contributed to criminality, weak morality, and poor physical attributes. Transplanting the testicles of younger men into those who were older would restore masculinity, he thought.  

Stanley began by using the testicles of executed prisoners — but he ran into a supply shortage. He solved this by using the testicles of animals, including goats and deer. At first, he physically implanted the testicles directly into the inmates. But that had complications, so he switched to a new plan: He ground up the animal testicles into a paste, which he injected into prisoners’ abdomens. By the end of his time at San Quentin, Stanley did an estimated 10,000 testicular procedures .

The Oncologist Who Injected Cancer Cells Into Patients and Prisoners

During the 1950s and 1960s, Sloan-Kettering Institute oncologist Chester Southam conducted research to learn how people’s immune systems would react when exposed to cancer cells. In order to find out, he injected live HeLa cancer cells into patients, generally without their permission. When patient consent was given, details around the true nature of the experiment were often kept secret. Southam first experimented on terminally ill cancer patients, to whom he had easy access. The result of the injection was the growth of cancerous nodules , which led to metastasis in one person.

Next, Southam experimented on healthy subjects , which he felt would yield more accurate results. He recruited prisoners, and, perhaps not surprisingly, their healthier immune systems responded better than those of cancer patients. Eventually, Southam returned to infecting the sick and arranged to have patients at the Jewish Chronic Disease Hospital in Brooklyn, NY, injected with HeLa cells. But this time, there was resistance. Three doctors who were asked to participate in the experiment refused, resigned, and went public.

The scandalous newspaper headlines shocked the public, and legal proceedings were initiated against Southern. Some in the scientific and medical community condemned his experiments, while others supported him. Initially, Southam’s medical license was suspended for one year, but it was then reduced to a probation. His career continued to be illustrious, and he was subsequently elected president of the American Association for Cancer Research.

The Aptly Named ‘Monster Study’

Pioneering speech pathologist Wendell Johnson suffered from severe stuttering that began early in his childhood. His own experience motivated his focus on finding the cause, and hopefully a cure, for stuttering. He theorized that stuttering in children could be impacted by external factors, such as negative reinforcement. In 1939, under Johnson’s supervision, graduate student Mary Tudor conducted a stuttering experiment, using 22 children at an Iowa orphanage. Half received positive reinforcement. But the other half were ridiculed and criticized for their speech, whether or not they actually stuttered. This resulted in a worsening of speech issues for the children who were given negative feedback.

The study was never published due to the multitude of ethical violations. According to The Washington Post , Tudor was remorseful about the damage caused by the experiment and returned to the orphanage to help the children with their speech. Despite his ethical mistakes, the Wendell Johnson Speech and Hearing Clinic at the University of Iowa bears Johnson's name and is a nod to his contributions to the field.

The Dermatologist Who Used Prisoners As Guinea Pigs

One of the biggest breakthroughs in dermatology was the invention of Retin-A, a cream that can treat sun damage, wrinkles, and other skin conditions. Its success led to fortune and fame for co-inventor Albert Kligman, a dermatologist at the University of Pennsylvania . But Kligman is also known for his nefarious dermatology experiments on prisoners that began in 1951 and continued for around 20 years. He conducted his research on behalf of companies including DuPont and Johnson & Johnson.

Kligman’s work often left prisoners with pain and scars as he used them as study subjects in wound healing and exposed them to deodorants, foot powders, and more for chemical and cosmetic companies. Dow once enlisted Kligman to study the effects of dioxin, a chemical in Agent Orange, on 75 inmates at Pennsylvania's Holmesburg Prison. The prisoners were paid a small amount for their participation but were not told about the potential side effects.

In the University of Pennsylvania’s journal, Almanac , Kligman’s obituary focused on his medical advancements, awards, and philanthropy. There was no acknowledgement of his prison experiments. However, it did mention that as a “giant in the field,” he “also experienced his fair share of controversy.”

The Endocrinologist Who Irradiated Prisoners

When the Atomic Energy Commission wanted to know how radiation affected male reproductive function, they looked to endocrinologist Carl Heller . In a study involving Oregon State Penitentiary prisoners between 1963 and 1973, Heller designed a contraption that would radiate their testicles at varying amounts to see what effect it had, particularly on sperm production. The prisoners also were subjected to repeated biopsies and were required to undergo vasectomies once the experiments concluded.

Although study participants were paid, it raised ethical issues about the potential coercive nature of financial compensation to prison populations. The prisoners were informed about the risks of skin burns, but likely were not told about the possibility of significant pain, inflammation, and the small risk of testicular cancer.

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• 20 Most Unethical Experiments in Psychology

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

Emma Eckstein

Electroshock Therapy on Children

Operation Midnight Climax

The Monster Study

Project MKUltra

The Aversion Project

Unnecessary Sexual Reassignment

Stanford Prison Experiment

Milgram Experiment

The Monkey Drug Trials

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Facial expressions experiment.

Little Albert

Bobo Doll Experiment

The Pit of Despair

The Bystander Effect

Learned Helplessness Experiment

Racism Among Elementary School Students

UCLA Schizophrenia Experiments

The Good Samaritan Experiment

Robbers Cave Experiment

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10 Psychological Experiments That Could Never Happen Today

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

1. The Little Albert Experiment

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

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

2. Asch Conformity Experiments

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

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

3. The Bystander Effect

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

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

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

4. The Milgram Experiment

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

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

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

5. Harlow’s Monkey Experiments

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

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

6. Learned Helplessness

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

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

7. Robbers Cave Experiment

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

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

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

8. The Monster Study

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

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

9. Blue Eyed versus Brown Eyed Students

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

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

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

10. The Stanford Prison Experiment

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

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

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

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

Ugly past of U.S. human experiments uncovered

Shocking as it may seem, U.S. government doctors once thought it was fine to experiment on disabled people and prison inmates. Such experiments included giving hepatitis to mental patients in Connecticut, squirting a pandemic flu virus up the noses of prisoners in Maryland, and injecting cancer cells into chronically ill people at a New York hospital.

Much of this horrific history is 40 to 80 years old, but it is the backdrop for a meeting in Washington this week by a presidential bioethics commission. The meeting was triggered by the government's apology last fall for federal doctors infecting prisoners and mental patients in Guatemala with syphilis 65 years ago.

U.S. officials also acknowledged there had been dozens of similar experiments in the United States — studies that often involved making healthy people sick.

An exhaustive review by The Associated Press of medical journal reports and decades-old press clippings found more than 40 such studies. At best, these were a search for lifesaving treatments; at worst, some amounted to curiosity-satisfying experiments that hurt people but provided no useful results.

Inevitably, they will be compared to the well-known Tuskegee syphilis study. In that episode, U.S. health officials tracked 600 black men in Alabama who already had syphilis but didn't give them adequate treatment even after penicillin became available.

These studies were worse in at least one respect — they violated the concept of "first do no harm," a fundamental medical principle that stretches back centuries.

"When you give somebody a disease — even by the standards of their time — you really cross the key ethical norm of the profession," said Arthur Caplan, director of the University of Pennsylvania's Center for Bioethics.

Attitude similar to Nazi experiments Some of these studies, mostly from the 1940s to the '60s, apparently were never covered by news media. Others were reported at the time, but the focus was on the promise of enduring new cures, while glossing over how test subjects were treated.

Attitudes about medical research were different then. Infectious diseases killed many more people years ago, and doctors worked urgently to invent and test cures. Many prominent researchers felt it was legitimate to experiment on people who did not have full rights in society — people like prisoners, mental patients, poor blacks. It was an attitude in some ways similar to that of Nazi doctors experimenting on Jews.

"There was definitely a sense — that we don't have today — that sacrifice for the nation was important," said Laura Stark, a Wesleyan University assistant professor of science in society, who is writing a book about past federal medical experiments.

The AP review of past research found:

• A federally funded study begun in 1942 injected experimental flu vaccine in male patients at a state insane asylum in Ypsilanti, Mich., then exposed them to flu several months later. It was co-authored by Dr. Jonas Salk, who a decade later would become famous as inventor of the polio vaccine.

Some of the men weren't able to describe their symptoms, raising serious questions about how well they understood what was being done to them. One newspaper account mentioned the test subjects were "senile and debilitated." Then it quickly moved on to the promising results.

• In federally funded studies in the 1940s, noted researcher Dr. W. Paul Havens Jr. exposed men to hepatitis in a series of experiments, including one using patients from mental institutions in Middletown and Norwich, Conn. Havens, a World Health Organization expert on viral diseases, was one of the first scientists to differentiate types of hepatitis and their causes.

A search of various news archives found no mention of the mental patients study, which made eight healthy men ill but broke no new ground in understanding the disease.

• Researchers in the mid-1940s studied the transmission of a deadly stomach bug by having young men swallow unfiltered stool suspension. The study was conducted at the New York State Vocational Institution, a reformatory prison in West Coxsackie. The point was to see how well the disease spread that way as compared to spraying the germs and having test subjects breathe it. Swallowing it was a more effective way to spread the disease, the researchers concluded. The study doesn't explain if the men were rewarded for this awful task.
• A University of Minnesota study in the late 1940s injected 11 public service employee volunteers with malaria, then starved them for five days. Some were also subjected to hard labor, and those men lost an average of 14 pounds. They were treated for malarial fevers with quinine sulfate. One of the authors was Ancel Keys, a noted dietary scientist who developed K-rations for the military and the Mediterranean diet for the public. But a search of various news archives found no mention of the study.
• For a study in 1957, when the Asian flu pandemic was spreading, federal researchers sprayed the virus in the noses of 23 inmates at Patuxent prison in Jessup, Md., to compare their reactions to those of 32 virus-exposed inmates who had been given a new vaccine.
• Government researchers in the 1950s tried to infect about two dozen volunteering prison inmates with gonorrhea using two different methods in an experiment at a federal penitentiary in Atlanta. The bacteria was pumped directly into the urinary tract through the penis, according to their paper.

The men quickly developed the disease, but the researchers noted this method wasn't comparable to how men normally got infected — by having sex with an infected partner. The men were later treated with antibiotics. The study was published in the Journal of the American Medical Association, but there was no mention of it in various news archives.

Though people in the studies were usually described as volunteers, historians and ethicists have questioned how well these people understood what was to be done to them and why, or whether they were coerced.

Victims for science Prisoners have long been victimized for the sake of science. In 1915, the U.S. government's Dr. Joseph Goldberger — today remembered as a public health hero — recruited Mississippi inmates to go on special rations to prove his theory that the painful illness pellagra was caused by a dietary deficiency. (The men were offered pardons for their participation.)

But studies using prisoners were uncommon in the first few decades of the 20th century, and usually performed by researchers considered eccentric even by the standards of the day. One was Dr. L.L. Stanley, resident physician at San Quentin prison in California, who around 1920 attempted to treat older, "devitalized men" by implanting in them testicles from livestock and from recently executed convicts.

Newspapers wrote about Stanley's experiments, but the lack of outrage is striking.

"Enter San Quentin penitentiary in the role of the Fountain of Youth — an institution where the years are made to roll back for men of failing mentality and vitality and where the spring is restored to the step, wit to the brain, vigor to the muscles and ambition to the spirit. All this has been done, is being done ... by a surgeon with a scalpel," began one rosy report published in November 1919 in The Washington Post.

Around the time of World War II, prisoners were enlisted to help the war effort by taking part in studies that could help the troops. For example, a series of malaria studies at Stateville Penitentiary in Illinois and two other prisons was designed to test antimalarial drugs that could help soldiers fighting in the Pacific.

It was at about this time that prosecution of Nazi doctors in 1947 led to the "Nuremberg Code," a set of international rules to protect human test subjects. Many U.S. doctors essentially ignored them, arguing that they applied to Nazi atrocities — not to American medicine.

The late 1940s and 1950s saw huge growth in the U.S. pharmaceutical and health care industries, accompanied by a boom in prisoner experiments funded by both the government and corporations. By the 1960s, at least half the states allowed prisoners to be used as medical guinea pigs.

But two studies in the 1960s proved to be turning points in the public's attitude toward the way test subjects were treated.

The first came to light in 1963. Researchers injected cancer cells into 19 old and debilitated patients at a Jewish Chronic Disease Hospital in the New York borough of Brooklyn to see if their bodies would reject them.

The hospital director said the patients were not told they were being injected with cancer cells because there was no need — the cells were deemed harmless. But the experiment upset a lawyer named William Hyman who sat on the hospital's board of directors. The state investigated, and the hospital ultimately said any such experiments would require the patient's written consent.

At nearby Staten Island, from 1963 to 1966, a controversial medical study was conducted at the Willowbrook State School for children with mental retardation. The children were intentionally given hepatitis orally and by injection to see if they could then be cured with gamma globulin.

Those two studies — along with the Tuskegee experiment revealed in 1972 — proved to be a "holy trinity" that sparked extensive and critical media coverage and public disgust, said Susan Reverby, the Wellesley College historian who first discovered records of the syphilis study in Guatemala.

'My back is on fire!' By the early 1970s, even experiments involving prisoners were considered scandalous. In widely covered congressional hearings in 1973, pharmaceutical industry officials acknowledged they were using prisoners for testing because they were cheaper than chimpanzees.

Holmesburg Prison in Philadelphia made extensive use of inmates for medical experiments. Some of the victims are still around to talk about it. Edward "Yusef" Anthony, featured in a book about the studies, says he agreed to have a layer of skin peeled off his back, which was coated with searing chemicals to test a drug. He did that for money to buy cigarettes in prison.

"I said 'Oh my God, my back is on fire! Take this ... off me!'" Anthony said in an interview with The Associated Press, as he recalled the beginning of weeks of intense itching and agonizing pain.

The government responded with reforms. Among them: The U.S. Bureau of Prisons in the mid-1970s effectively excluded all research by drug companies and other outside agencies within federal prisons.

As the supply of prisoners and mental patients dried up, researchers looked to other countries.

It made sense. Clinical trials could be done more cheaply and with fewer rules. And it was easy to find patients who were taking no medication, a factor that can complicate tests of other drugs.

Additional sets of ethical guidelines have been enacted, and few believe that another Guatemala study could happen today. "It's not that we're out infecting anybody with things," Caplan said.

Still, in the last 15 years, two international studies sparked outrage.

One was likened to Tuskegee. U.S.-funded doctors failed to give the AIDS drug AZT to all the HIV-infected pregnant women in a study in Uganda even though it would have protected their newborns. U.S. health officials argued the study would answer questions about AZT's use in the developing world.

The other study, by Pfizer Inc., gave an antibiotic named Trovan to children with meningitis in Nigeria, although there were doubts about its effectiveness for that disease. Critics blamed the experiment for the deaths of 11 children and the disabling of scores of others. Pfizer settled a lawsuit with Nigerian officials for $75 million but admitted no wrongdoing.

Last year, the U.S. Department of Health and Human Services' inspector general reported that between 40 and 65 percent of clinical studies of federally regulated medical products were done in other countries in 2008, and that proportion probably has grown. The report also noted that U.S. regulators inspected fewer than 1 percent of foreign clinical trial sites.

Monitoring research is complicated, and rules that are too rigid could slow new drug development. But it's often hard to get information on international trials, sometimes because of missing records and a paucity of audits, said Dr. Kevin Schulman, a Duke University professor of medicine who has written on the ethics of international studies.

Syphilis study These issues were still being debated when, last October, the Guatemala study came to light.

In the 1946-48 study, American scientists infected prisoners and patients in a mental hospital in Guatemala with syphilis, apparently to test whether penicillin could prevent some sexually transmitted disease. The study came up with no useful information and was hidden for decades.

Story: U.S. apologizes for Guatemala syphilis experiments

The Guatemala study nauseated ethicists on multiple levels. Beyond infecting patients with a terrible illness, it was clear that people in the study did not understand what was being done to them or were not able to give their consent. Indeed, though it happened at a time when scientists were quick to publish research that showed frank disinterest in the rights of study participants, this study was buried in file drawers.

"It was unusually unethical, even at the time," said Stark, the Wesleyan researcher.

"When the president was briefed on the details of the Guatemalan episode, one of his first questions was whether this sort of thing could still happen today," said Rick Weiss, a spokesman for the White House Office of Science and Technology Policy.

That it occurred overseas was an opening for the Obama administration to have the bioethics panel seek a new evaluation of international medical studies. The president also asked the Institute of Medicine to further probe the Guatemala study, but the IOM relinquished the assignment in November, after reporting its own conflict of interest: In the 1940s, five members of one of the IOM's sister organizations played prominent roles in federal syphilis research and had links to the Guatemala study.

So the bioethics commission gets both tasks. To focus on federally funded international studies, the commission has formed an international panel of about a dozen experts in ethics, science and clinical research. Regarding the look at the Guatemala study, the commission has hired 15 staff investigators and is working with additional historians and other consulting experts.

The panel is to send a report to Obama by September. Any further steps would be up to the administration.

Some experts say that given such a tight deadline, it would be a surprise if the commission produced substantive new information about past studies. "They face a really tough challenge," Caplan said.

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Three Psychology Experiments That Pushed the Limit of Ethics

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

The ultimate isolation: Hebb’s “pathological boredom”

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

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

How malleable is our willpower?

The facebook study: how contagious are emotions.

Credit: Pixabay

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

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Understanding the Milgram Experiment in Psychology

A closer look at Milgram's controversial studies of obedience

Isabelle Adam (CC BY-NC-ND 2.0) via Flickr

Factors That Influence Obedience

• Ethical Concerns
• Replications

How far do you think people would go to obey an authority figure? Would they refuse to obey if the order went against their values or social expectations? Those questions were at the heart of an infamous and controversial study known as the Milgram obedience experiments.

Yale University  psychologist   Stanley Milgram  conducted these experiments during the 1960s. They explored the effects of authority on obedience. In the experiments, an authority figure ordered participants to deliver what they believed were dangerous electrical shocks to another person. These results suggested that people are highly influenced by authority and highly obedient . More recent investigations cast doubt on some of the implications of Milgram's findings and even the results and procedures themselves. Despite its problems, the study has, without question, made a significant impact on psychology .

At a Glance

Milgram's experiments posed the question: Would people obey orders, even if they believed doing so would harm another person? Milgram's findings suggested the answer was yes, they would. The experiments have long been controversial, both because of the startling findings and the ethical problems with the research. More recently, experts have re-examined the studies, suggesting that participants were often coerced into obeying and that at least some participants recognized that the other person was just pretending to be shocked. Such findings call into question the study's validity and authenticity, but some replications suggest that people are surprisingly prone to obeying authority.

History of the Milgram Experiments

Milgram started his experiments in 1961, shortly after the trial of the World War II criminal Adolf Eichmann had begun. Eichmann’s defense that he was merely following instructions when he ordered the deaths of millions of Jews roused Milgram’s interest.

In his 1974 book "Obedience to Authority," Milgram posed the question, "Could it be that Eichmann and his million accomplices in the Holocaust were just following orders? Could we call them all accomplices?"

Procedure in the Milgram Experiment

The participants in the most famous variation of the Milgram experiment were 40 men recruited using newspaper ads. In exchange for their participation, each person was paid $4.50.

Milgram developed an intimidating shock generator, with shock levels starting at 15 volts and increasing in 15-volt increments all the way up to 450 volts. The many switches were labeled with terms including "slight shock," "moderate shock," and "danger: severe shock." The final three switches were labeled simply with an ominous "XXX."

Each participant took the role of a "teacher" who would then deliver a shock to the "student" in a neighboring room whenever an incorrect answer was given. While participants believed that they were delivering real shocks to the student, the “student” was a confederate in the experiment who was only pretending to be shocked.

As the experiment progressed, the participant would hear the learner plead to be released or even complain about a heart condition. Once they reached the 300-volt level, the learner would bang on the wall and demand to be released.

Beyond this point, the learner became completely silent and refused to answer any more questions. The experimenter then instructed the participant to treat this silence as an incorrect response and deliver a further shock.

Most participants asked the experimenter whether they should continue. The experimenter then responded with a series of commands to prod the participant along:

• "Please continue."
• "The experiment requires that you continue."
• "It is absolutely essential that you continue."
• "You have no other choice; you must go on."

Results of the Milgram Experiment

In the Milgram experiment, obedience was measured by the level of shock that the participant was willing to deliver. While many of the subjects became extremely agitated, distraught, and angry at the experimenter, they nevertheless continued to follow orders all the way to the end.

Milgram's results showed that 65% of the participants in the study delivered the maximum shocks. Of the 40 participants in the study, 26 delivered the maximum shocks, while 14 stopped before reaching the highest levels.

Why did so many of the participants in this experiment perform a seemingly brutal act when instructed by an authority figure? According to Milgram, there are some situational factors that can explain such high levels of obedience:

• The physical presence of an authority figure dramatically increased compliance .
• The fact that Yale (a trusted and authoritative academic institution) sponsored the study led many participants to believe that the experiment must be safe.
• The selection of teacher and learner status seemed random.
• Participants assumed that the experimenter was a competent expert.
• The shocks were said to be painful, not dangerous.

Later experiments conducted by Milgram indicated that the presence of rebellious peers dramatically reduced obedience levels. When other people refused to go along with the experimenter's orders, 36 out of 40 participants refused to deliver the maximum shocks.

More recent work by researchers suggests that while people do tend to obey authority figures, the process is not necessarily as cut-and-dried as Milgram depicted it.

In a 2012 essay published in PLoS Biology , researchers suggested that the degree to which people are willing to obey the questionable orders of an authority figure depends largely on two key factors:

• How much the individual agrees with the orders
• How much they identify with the person giving the orders

While it is clear that people are often far more susceptible to influence, persuasion , and obedience than they would often like to be, they are far from mindless machines just taking orders. 

Another study that analyzed Milgram's results concluded that eight factors influenced the likelihood that people would progress up to the 450-volt shock:

• The experimenter's directiveness
• Legitimacy and consistency
• Group pressure to disobey
• Indirectness of proximity
• Intimacy of the relation between the teacher and learner
• Distance between the teacher and learner

Ethical Concerns in the Milgram Experiment

Milgram's experiments have long been the source of considerable criticism and controversy. From the get-go, the ethics of his experiments were highly dubious. Participants were subjected to significant psychological and emotional distress.

Some of the major ethical issues in the experiment were related to:

• The use of deception
• The lack of protection for the participants who were involved
• Pressure from the experimenter to continue even after asking to stop, interfering with participants' right to withdraw

Due to concerns about the amount of anxiety experienced by many of the participants, everyone was supposedly debriefed at the end of the experiment. The researchers reported that they explained the procedures and the use of deception.

Critics of the study have argued that many of the participants were still confused about the exact nature of the experiment, and recent findings suggest that many participants were not debriefed at all.

Replications of the Milgram Experiment

While Milgram’s research raised serious ethical questions about the use of human subjects in psychology experiments , his results have also been consistently replicated in further experiments. One review further research on obedience and found that Milgram’s findings hold true in other experiments. In one study, researchers conducted a study designed to replicate Milgram's classic obedience experiment. The researchers made several alterations to Milgram's experiment.

• The maximum shock level was 150 volts as opposed to the original 450 volts.
• Participants were also carefully screened to eliminate those who might experience adverse reactions to the experiment.

The results of the new experiment revealed that participants obeyed at roughly the same rate that they did when Milgram conducted his original study more than 40 years ago.

Some psychologists suggested that in spite of the changes made in the replication, the study still had merit and could be used to further explore some of the situational factors that also influenced the results of Milgram's study. But other psychologists suggested that the replication was too dissimilar to Milgram's original study to draw any meaningful comparisons.

One study examined people's beliefs about how they would do compared to the participants in Milgram's experiments. They found that most people believed they would stop sooner than the average participants. These findings applied to both those who had never heard of Milgram's experiments and those who were familiar with them. In fact, those who knew about Milgram's experiments actually believed that they would stop even sooner than other people.

Another novel replication involved recruiting participants in pairs and having them take turns acting as either an 'agent' or 'victim.' Agents then received orders to shock the victim. The results suggest that only around 3.3% disobeyed the experimenter's orders.

Recent Criticisms and New Findings

Psychologist Gina Perry suggests that much of what we think we know about Milgram's famous experiments is only part of the story. While researching an article on the topic, she stumbled across hundreds of audiotapes found in Yale archives that documented numerous variations of Milgram's shock experiments.

Participants Were Often Coerced

While Milgram's reports of his process report methodical and uniform procedures, the audiotapes reveal something different. During the experimental sessions, the experimenters often went off-script and coerced the subjects into continuing the shocks.

"The slavish obedience to authority we have come to associate with Milgram’s experiments comes to sound much more like bullying and coercion when you listen to these recordings," Perry suggested in an article for Discover Magazine .

Few Participants Were Really Debriefed

Milgram suggested that the subjects were "de-hoaxed" after the experiments. He claimed he later surveyed the participants and found that 84% were glad to have participated, while only 1% regretted their involvement.

However, Perry's findings revealed that of the 700 or so people who took part in different variations of his studies between 1961 and 1962, very few were truly debriefed.

A true debriefing would have involved explaining that the shocks weren't real and that the other person was not injured. Instead, Milgram's sessions were mainly focused on calming the subjects down before sending them on their way.

Many participants left the experiment in a state of considerable distress. While the truth was revealed to some months or even years later, many were simply never told a thing.

Variations Led to Differing Results

Another problem is that the version of the study presented by Milgram and the one that's most often retold does not tell the whole story. The statistic that 65% of people obeyed orders applied only to one variation of the experiment, in which 26 out of 40 subjects obeyed.

In other variations, far fewer people were willing to follow the experimenters' orders, and in some versions of the study, not a single participant obeyed.

Participants Guessed the Learner Was Faking

Perry even tracked down some of the people who took part in the experiments, as well as Milgram's research assistants. What she discovered is that many of his subjects had deduced what Milgram's intent was and knew that the "learner" was merely pretending.

Such findings cast Milgram's results in a new light. It suggests that not only did Milgram intentionally engage in some hefty misdirection to obtain the results he wanted but that many of his participants were simply playing along.

An analysis of an unpublished study by Milgram's assistant, Taketo Murata, found that participants who believed they were really delivering a shock were less likely to obey, while those who did not believe they were actually inflicting pain were more willing to obey. In other words, the perception of pain increased defiance, while skepticism of pain increased obedience.

A review of Milgram's research materials suggests that the experiments exerted more pressure to obey than the original results suggested. Other variations of the experiment revealed much lower rates of obedience, and many of the participants actually altered their behavior when they guessed the true nature of the experiment.

Impact of the Milgram Experiment

Since there is no way to truly replicate the experiment due to its serious ethical and moral problems, determining whether Milgram's experiment really tells us anything about the power of obedience is impossible to determine.

So why does Milgram's experiment maintain such a powerful hold on our imaginations, even decades after the fact? Perry believes that despite all its ethical issues and the problem of never truly being able to replicate Milgram's procedures, the study has taken on the role of what she calls a "powerful parable."

Milgram's work might not hold the answers to what makes people obey or even the degree to which they truly obey. It has, however, inspired other researchers to explore what makes people follow orders and, perhaps more importantly, what leads them to question authority.

Recent findings undermine the scientific validity of the study. Milgram's work is also not truly replicable due to its ethical problems. However, the study has led to additional research on how situational factors can affect obedience to authority.

Milgram’s experiment has become a classic in psychology , demonstrating the dangers of obedience. The research suggests that situational variables have a stronger sway than personality factors in determining whether people will obey an authority figure. However, other psychologists argue that both external and internal factors heavily influence obedience, such as personal beliefs and overall temperament.

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