Theories Social Psychology Controversial and Unethical Psychology Experiments By Kendra Cherry, MSEd Kendra Cherry, MSEd Kendra Cherry, MS, is a psychosocial rehabilitation specialist, psychology educator, and author of the "Everything Psychology Book." Learn about our editorial process Updated on December 05, 2023 Fact checked Verywell Mind content is rigorously reviewed by a team of qualified and experienced fact checkers. Fact checkers review articles for factual accuracy, relevance, and timeliness. We rely on the most current and reputable sources, which are cited in the text and listed at the bottom of each article. Content is fact checked after it has been edited and before publication. Learn more. by Shereen Lehman, MS Fact checked by Shereen Lehman, MS Shereen Lehman, MS, is a healthcare journalist and fact checker. She has co-authored two books for the popular Dummies Series (as Shereen Jegtvig). Learn about our editorial process Print Trending Videos Close this video player 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. 1 Harlow's Pit of Despair Martin Rogers / Getty Images 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. Variations 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. 2 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 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. 3 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 Experiment 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. The Results 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." 4 Watson and Rayner's Little Albert Experiment Shanelle Hulse / EyeEm / Getty Images If you have ever taken an Introduction to Psychology class, then you are probably at least a little familiar with Little Albert. The Experiment 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. 5 Seligman's Look Into Learned Helplessness Elena Pejchinova / Getty Images 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. The Experiment 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. The Results 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. The Process of Conducting Ethical Research in Psychology 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. The Most Famous Social Psychology Experiments Ever Performed 7 Sources Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. 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." See Our Editorial Process Meet Our Review Board Share Feedback Was this page helpful? Thanks for your feedback! What is your feedback? Helpful Report an Error Other Submit