--- title: "Harlow's Pit of Despair: Cruel, Shocking Psychological Research" description: "Ask his students, and he might have been a visionary. Ask his contemporaries, and he might have been a mad scientist. Ask the experts of today, and he might have been a monster. Of all of the myriad pioneers of psychological research, there are few with a reputation quite so extreme as Dr. Harry F. Harlow, whose work on dependency, social isolation, and maternal separation laid the groundwork for entire fields of modern study—but did so at a shocking cost to his subjects, and in so doing, was one of the primary reasons why ethics in psychology are regarded with such critical importance today.\n\nIn this article, we'll be digging into the demented scientific research of Harry Harlow: its cruel and unusual design, its critical revelations on the nature of interpersonal attachment, and the stunning degree to which Harlow's legacy has shaped the field of psychology today.\n\n## The Man; The Question\n\nTo understand the Harlow experiments, we've first got to understand the man who created them. Born Harry Frederick Israel in Fairfield, Iowa, in 1905, the boy who later became Harry Harlow is an enigma to modern-day biographers. Even today, we know little about his childhood years, except for excerpts from his own unfinished biography, suggesting a distant mother who modern theorists would describe—in part because of Harlow's own work—as avoidant or dismissive. Harlow also implied that he struggled with depression across his life, even in childhood. Although he was a smart boy, he was often bored by his surroundings, and even feared from a young age that he might eventually go insane. As a young adult, he made his way to Stanford University, gaining entry via a special aptitude test, but whatever his aptitude might have been, he struggled to express it in his early years as an English major. Beset with atrocious grades after just a semester, and clearly not showing a whole lot of promise in the field, Harlow was forced to look for other options. As his relief valve, he employed a tried-and-true tactic among struggling undergraduates of any generation: He became a psych major, and basically hoped for the best.\n\nOver the next six years, Harlow would earn first an undergraduate degree and then a doctorate at Stanford, spending most of his time studying directly under one Lewis Madison Terman. His mentor is remembered today for his drastic improvements on the Stanford-Binet Intelligence Scales—or, basically, the modern IQ test—and a long-term study he carried out, called the Genetic Studies of Genius, which was about…well, the genetic studies of genius. However, he was also very into eugenics at the same time that Harlow was studying under him. From what we can tell, Harlow didn't seem to adopt quite those same beliefs, but as we'll see shortly, there's more than one way to be a bit unhinged. Around this same time, he changed his name from Harry Israel to Harry Harlow; it was the early 1930s, and while Harlow himself wasn't Jewish, he feared that having a Jewish-sounding last name would bring on negative consequences in both his life and his career. The person behind that change, and the one who decided he was to be called Harlow? His mentor, Lewis Terman.\n\nFrom Stanford, Harlow made his way to the University of Wisconsin at Madison to become a professor. Without a laboratory on campus, and without any indication from the university that they intended to give him one, Harlow set up his own research space off-campus in what would later be named the Primate Laboratory. Harlow wasn't particularly interested in working with humans, and even though he was conducting his research in psychology's wild-west era when he probably could have gotten away with some pretty insane research designs, his particular research might have been a step too far for human-subjects research even before the introduction of modern research ethics. Harlow's early work at Madison was done via a local zoo, who supplied him with primates to engage with what he would eventually call the Wisconsin General Testing Apparatus. Basically a memory and cognition test, the Apparatus yielded some fairly interesting results for Harlow, but the most important one of all, wasn't actually one he had expected to find. Within a few tests of a given primate, Harlow realized that the primates were beginning to figure out strategies to get through the tests he was running.\n\nBut although Harlow spent a while trying to figure out how the monkeys were developing those strategies—or, 'learning to learn', as he called it—that line of questioning ultimately became a gateway into the one that would make Harlow's entire career. You see, during the time that Harlow was running his first large-scale primate experiments, he decided to put together a breeding colony of monkeys in his lab. The primates he chose were rhesus macaques, an Old World monkey from southeast Asia with complex social groups, internal familial relationships, and close anatomical and physiological similarities to humans. During the establishment of the breeding colony, Harlow and his students were able to witness first-hand how healthy relationships between baby rhesus monkeys and their mothers developed, and when Harlow decided he wanted to rear the infant monkeys in a nursery rather than dealing with their protective mothers whenever he wanted to use one in an experiment, he began to notice something else. The nursery-raised macaques were coming out different—not physically, but behaviorally—and Harlow wanted to know why.\n\nHarlow and his contemporaries were living at a time in which infant attachment to their parents, especially their mothers, was not well-understood. Opinions on the impact of infant separation from a mother ran the gamut; some theorists postulated it had to do with a dependent, feeding relationship with a mother, purely transactional at first, while others contended that it barely mattered at all. Still others claimed that humans only organized into familial structures, and engaged with society, to gain steady access to sexual contact. Many famous or well-regarded psychologists of the era advised mothers and fathers not to even hold their children if it wasn't necessary, let alone to indulge their cries, for fear of spoiling them. As behaviorist John Watson once wrote, apparently without a hint of irony: \"Do not overindulge them. Do not kiss them goodnight. Rather, give a brief bow and shake their hand before turning off the light.\" The American standard for nurseries at the time was to intentionally make them cold, distant, and inhospitable to positive attachment.\n\nBut Harlow, along with a handful of other psychologists at the time, took a different tack. Depending on your perspective, you might say Harlow had a hunch. Or, you might say that he had more experience than most on the subject, after struggling to make sense of his own mother's behavior toward him as a boy. After all, that's the nature of every Freudian slip in psychology: saying one thing, and meaning your mother. But regardless, Harlow contended that an infant's bond with its mother mattered very, very much, and that it would have a profound impact on a child not just in infancy, but during the longer course of development as well.\n\n## The Nature of Love\n\nHarlow's first really consequential experiment came over twenty years after he first began working at the University of Wisconsin, in 1957. By then, he had noticed the strangeness of some of his rhesus monkeys when they were raised away from their mothers, and he decided to run a longer and more organized study. He and his research team began separating infant monkeys from their mothers at birth, and raising them in what was essentially complete isolation other than their interactions with researchers. It seems obvious now, but at the time, it was a surprise for Harlow to learn that this impacted the monkeys severely. Left alone and deprived of stimulus, the monkeys learned to cope in all manner of ways: zoning out so hard they appeared to be doing what we now know to be dissociating, or pacing incessantly inside their cages, or even harming themselves. They proved incapable of interacting with other monkeys when they were eventually given the opportunity to do so, and some were so shaken by the experience that they stopped eating entirely, and starved to death.\n\nThat was already a stunning finding, considering how starkly it ran contrary to the wisdom of the time. But Harlow had also picked up on one other detail: specifically, that the monkeys had shown a common behavior in clinging onto the diapers the research team had given them. Those diapers were made of cloth, they were soft, and the infant monkeys seemed to be taking comfort in them. That led Harlow toward the question of comfort in a maternal relationship—and the way he went about examining the nature of maternal comfort, would write his name into the history books.\n\nHarlow's next experiment exposed a new generation of infant monkeys to a pair of surrogate mothers…but not living ones. Each monkey involved in this study would be raised in an enclosure with two dummies, one made of cold, inflexible wire, and one made of soft cloth. In order to directly challenge his peers' contention that a mother-child relationship was all about accessing food, Harlow ensured that some monkeys would have their milk bottle stored in the cloth mother, while others had it stored in the wire mother. In all cases, no matter which of the surrogate mothers the monkeys had to use to get their milk, they nonetheless spent the vast majority of their time with the cloth mother. Monkeys that had a milk-giving wire mother would interact with it only minimally, and usually to feed; those that had a milk-giving cloth mother, ignored the wire mother entirely. But the real stunner came when those same monkeys were exposed to new environments, with new stimuli. When they were placed into those environments with the companionship of the cloth mother, they were curious, interactive, and at times even brave. When they were feeling less brave, they'd retreat back to the cloth mother or even the wire mother for safety. But when they were taken away from their surrogate mothers and placed into the same situations, they broke down, trying to hide, crying, and howling to return to safety.\n\nOf all the ways Harlow's experiment could have gone, there were few conceivable outcomes that might have screamed the conclusions at him any more conclusively. Harlow had also run experiments on infant monkeys that had grown up only with their mothers, and no peer exposure, and when those monkeys showed fear and aggressiveness when exposed to same-age peers, Harlow's takeaways grew stronger still in their conviction. The infant-mother relationship wasn't only about food, and in fact, it didn't even need food as a central component. Instead, it was all about comfort, safety, and security, feelings in which physical contact with the mother seemed to be absolutely critical. The implications for parents of that time were horrifying; after following the advice of the best psychologists of the day, they'd taken steps to raise their children in a way that, Harlow had now shown, was going to leave their children emotionally and developmentally stunted for the long term. His findings were confirmation to other theorists who'd been struggling to make the same point to the general public, and the idea of comfort as a cornerstone in child development really began to take on. It seems ridiculous to imagine now, but these were, at the time, truly groundbreaking ideas, and ones that shook the entire field of psychology to its core.\n\n## Isolation and Deprivation\n\nWith his grand thesis on the centrality of comfort now firmly interjected into American public consciousness, Harlow turned his attention back to his flock of rhesus monkeys. Now, the question at hand would be isolation. We've already mentioned the results of isolation that Harlow had observed in early experiments; that is, that infant monkeys raised without their mothers and without interaction with any other monkeys proved to be behaviorally strange compared to monkeys with normal upbringings. They would stare off into space for hours, harm themselves, and display all other manner of odd impulses in order to cope with their situation, and they proved utterly incapable of interacting with other monkeys after living in isolation for so long. Faced with those early results, Harlow did what any psychologist of the mid-20th century would have done: he looked at the situation he had created for his subjects, and endeavored to make it so much worse.\n\nIn his subsequent studies, Harlow would expose infant monkeys to one of two conditions: partial social isolation, and complete social isolation. In the partial option, the monkeys would be barred from interacting with each other, kept in individual, bare wire cages set apart from each other, with no means to receive any level of physical comfort. But as it turns out, those monkeys had it easy. The total-deprivation group were raised in isolation chambers, from basically the moment of birth, for periods as long as a total of fifteen years in some cases, well over half of the average captive rhesus monkey's entire lifespan.\n\nThe results were exactly what you might expect. In the totally isolated monkeys, the pacing came back, the dissociation came back, and the withdrawn, curled-up thumb-sucking behaviors, reported by Harlow as non-nutritional sucking, came back too. They became hostile toward any outside stimulus, including researchers, and showed hostility toward their own bodies as well. But the behaviors were at their worst, when these totally isolated monkeys were exposed to others for the first time. For this, we'll quote directly from Harlow, published in 1965: \"No monkey has died during isolation. When initially removed from total social isolation, however, they usually go into a state of emotional shock, characterized by […] autistic self-clutching and rocking [….] One of six monkeys isolated for 3 months refused to eat after release and died 5 day later. The autopsy report attributed death to emotional anorexia. A second animal in the same group also refused to eat and probably would have died had we not been prepared to resort to forced feeding.\"\n\nIn one particularly interesting detail, the emotional anorexia Harlow described appeared most strongly in infants that were isolated for just three months before being exposed to other monkeys. Infants who were isolated for longer periods, and matured a bit more in their solitude, certainly didn't enjoy their initial exposure to other monkeys, but the results were far less destructive. Harlow also noticed that when the monkeys, particularly the three-month isolates, were given the chance to spend more time with other monkeys around their age, they were able to come out of their shells and even rehabilitate themselves cognitively and socially. Said Harlow: \"In human terms they are the children salvaged from the orphanage or inadequate home within the first year of life\". The monkeys who'd been isolated for longer, however, showed severely impaired recovery, and were totally averse to contact play, or roughhousing, that would be common among normal macaques of the same age. In Harlow's writing: \"The effects of 6 months of total social isolation were so devastating and debilitating that we had assumed initially that 12 months of isolation would not produce any additional decrement. This assumption proved to be false; 12 months of isolation almost obliterated the animals socially [….]\". So stunted was the 12-month group's social growth that when it came time to have them interact with normally raised monkeys from a control group, quote, \"the controls became increasingly aggressive toward the helpless isolate animals and might have killed them had we continued social testing\".\n\nBy the end of this run of studies, Harlow had concluded not only that a lack of social interaction could nearly entirely destroy an infant's capacity to function either at the present age or later in life, but that there was only a narrow, critical window for much of the damage to be undone. A three-month-old monkey could be taken out of isolation, placed into Harlow's rough equivalent of a nursery, and shown by their peers how to act, but the same couldn't be said for six-month-old or twelve-month-old monkeys. By Harlow's extrapolations, those were roughly the same developmental markers as a two-year-old child and a four-year-old child, respectively. And when those monkeys were left to interact only with peers that had also experienced the same isolation, they were able to interact only minimally, using the crude mechanisms they basically invented themselves. Those that eventually had children of their own were sometimes capable of not killing their own infants, but struggled to do anything more than that. But that news did come with one critical caveat: six-month-old monkeys who were placed into recovery groups not with normal six-month-old peers, but normal three-month-old peers, had a far better chance at a complete social recovery.\n\n## The Pit of Despair\n\nNow, do you remember when we said earlier that Harlow, when faced by real and fascinating results on attachment, decided to do the mid-20th-century-psychologist thing and make life even more of a living hell for his subjects? Well, it was at this point in the final years of Harlow's career that he decided to repeat the cycle one more time. Harlow had always had a soft spot for choosing rather unconventional, or even sensationalist names for his own projects, including some that we're not going to mention because we'd rather not have this article taken down. But the one we do need to discuss, is a series of isolation chambers that Harlow referred to as the Pit of Despair.\n\nHarlow's intent with this round of studies was to attempt to build a model for understanding depression in animals, and if Harlow was going to do that, then he was going to need some depressed animals. To make that happen, he and his research partner at that time, Stephen Suomi, designed a stainless-steel trough that they technically termed a vertical chamber apparatus. Basically, it was a steel pit with a wire-mesh floor, a food box, and a water-bottle holder, with a top designed so that the monkeys inside couldn't use it to hang or entertain themselves. The sides of it were made to be slippery, sloping down to a narrow point where the monkey inside would barely have room to move. And this time, Harlow's subjects weren't infant monkeys removed from their mothers at birth. They were monkeys of an age at least three months old, who had already formed bonds with their mothers and their nursery playmates. Harlow's express intention was to shatter those bonds, and keep the monkeys in complete isolation and complete darkness for months.\n\nThe result, of course, was precisely what you might expect. After a day or two spent attempting to escape, the monkeys inside would give up, descend to the bottom of the apparatus, curl up into a ball, and, by all outward appearances, languish in their despair with no opportunity to do anything else. As Harlow's collaborator Suomi wrote it later, no monkey was able to guard against the psychological anguish they seemed to experience inside the cage, and none of them emerged without sustaining serious psychological damage for the rest of their lives. After thirty days in the pit, monkeys who were released would refuse to interact with other monkeys, engage with any external stimuli, or even move of their own volition. For the most part, they would remain huddled and attempting to self-soothe by clutching at their own bodies. Those behaviors would persist for months in most cases, and they only got worse the longer a monkey had spent in the pit before release. Then, Harlow and his students would attempt to rehabilitate them, in efforts that were basically unsuccessful across the world. Harlow would insist in his later years that the studies had provided data that had major implications for the study of depression, but decades later, those same studies have been only minimally referenced in any work related to treatment.\n\n## Controversies and Breakthroughs\n\nHarlow would die in Tucson, Arizona, at the age of 76 in 1981, by which time much of the public reaction to his work had already become firmly entrenched. With Harlow's publications, and the slow evolution of his work from the genuinely groundbreaking to the increasingly macabre, his name had become the source of powerful controversies within the scientific community, and controversies that would only grow more and more intense after the end of his life.\n\nNow, before we get into the many, many, many negatives of Harlow's work, we do need to take a moment and acknowledge the real value of what he achieved. Harlow's work on the importance of maternal attachment came at a time when it was desperately needed, and when conventional wisdom suggested that children were best left stranded in social and parental isolation. Harlow's work clearly demonstrated, and later studies have since confirmed, that such treatment of children—whether monkey or human—would seriously stunt a child's ability to grow, erase critical social skills, and have an impact that would echo throughout the rest of their lives. For his work, Harlow won national acclaim in the United States, and he was even named president of the APA, or American Psychological Association, which governs academics across the entire field of psychological research.\n\nBut Harlow's work also made him one of a few members of one of modern psychology's most exclusive clubs: the researchers whose work inspired the creation of ethical standards in human and animal psychological research, not because of the lessons Harlow's research taught anybody, but to ensure that research like it could never take place again. One of Harlow's own former students, University of Washington professor Gene Sackett, has since explained how Harlow's experiments basically kicked off the animal liberation movement in the US, and forced America to reckon with the treatment of animals in laboratory settings. Today, the use of lab animals is tightly regulated by the APA and other governing bodies, who refuse to sponsor, endorse, or even allow the use of research institutions for human or animal experimentation that is deemed to have too great of a risk of harm to its subjects.\n\nWhen it comes to educating the next generation of psychologists, Harlow's example, and the sheer visceral horror it evokes in people who learn about it, have made it a flagship case of what not to do. Ask a first-year undergraduate psychology student at any American university, fresh off an introductory class, and they may or may not be able to explain the mechanisms of interpersonal attachment or the models that guide our understanding of human or animal depression. But they sure as hell know Harlow's monkeys, and can probably recount a detailed explanation from their professors or teaching assistants on just why research like that is such a bad idea.\n\nHarlow's personal reputation hasn't survived, either, and it's not as if he helped his own case in trying to preserve it. In his later years, he would reveal to interviewers and students his disdain for the monkeys he'd used as subjects, including with this gem of a quote from 1974: \"The only thing I care about is whether the monkeys will turn out a property I can publish. I don't have any love for them. Never have. I really don't like animals. I despise cats, I hate dogs. How could you like a monkey?\" Routinely, Harlow would attempt to frame any disputes around the welfare of his animals as a matter of public relations or perception, and would dismiss any genuine care for the animals shown by his many critics, as either being misguided or fabricating their concern outright. As another of his former students said later in life, despite himself continuing deprivation experiments with animal subjects, quote, \"it's as if he sat down and said, 'I'm only going to be around another ten years. What I'd like to do, then, is leave a great big mess behind.' If that was his aim, he did a perfect job.\"\n\nNot only that, but Harlow's own motivations for conducting some of his most questionable studies has been repeatedly called into question. As we alluded to before, this was a man who devoted his life to studying mother-child attachment, and often ripping away that attachment from his subjects, after having been deprived of such attachment himself. There were side experiments we didn't even mention before, including the use of a surrogate-mother machine that attacked baby monkeys with spikes or cold air to simulate real-life abuse. The results, by the way, showed that those baby monkeys were still unable to bring themselves to stop seeking comfort from the evil, but cloth-covered abusive surrogates. Harlow's later Pit of Despair experiments came at a time in his life when Harlow himself entered a well of despair, following the death of his second wife after a long battle with cancer. With his own personal depression came disinterest in attachment, and far more of an interest in the isolation of his subjects. When asked by another faculty member at the University of Wisconsin why on Earth Harlow was using these demented pits for his research, Harlow reportedly responded, \"Because that's how it feels when you're depressed.\" One of his former doctoral students he'd worked with during the Pit of Despair years has since explained that he had to be talked out of an even more descriptive name, the Dungeon of Despair, for fears of how the university and Harlow's own peers might react. Other critics pointed out that the Pit of Despair research was generating results that might have been shocking in the 1950s—for example, the idea that living organisms might experience negative effects because of social deprivation—but were well-understood by the time those later experiments actually took place. Said writer Wayne Booth, \"Harry Harlow and his colleagues go on torturing their nonhuman primates decade after decade, invariably proving what we all knew in advance—that social creatures can be destroyed by destroying their social ties\".\n\nIn retrospect, it's impossible to dismiss the life and work of Harry Harlow in its entirety. Modern nurseries, social services, maternity wards, and countless individual relationships between mothers, fathers, and their children have been fundamentally changed for the better because of what Harlow was able to show the world with his studies. But at the same time, Harlow left behind a long and indisputable legacy of intense pain and even depravity in the name of science. Harlow and his work did, indeed, represent progress, but at a price of decades of unyielding cruelty. He was a man one part visionary, one part mad scientist, and one part pure madman. The world wouldn't be the same without him, and yet, it is imperative that the field of psychology never hosts a figure quite like him again.\n\n## Key Takeaways\n\n- Harry Harlow's experiments on maternal separation and social isolation in monkeys were pivotal in understanding the importance of maternal attachment.\n- Harlow's work demonstrated that comfort, safety, and security are crucial for infant development, challenging prevailing beliefs.\n- The ethical implications of Harlow's research led to significant changes in psychological research standards, emphasizing the protection of subjects.\n- Harlow's controversial methods, including the Pit of Despair, highlighted the severe psychological damage caused by social deprivation.\n- Despite his groundbreaking contributions, Harlow's legacy is marred by the extreme cruelty inflicted on his animal subjects.\n\n## Frequently Asked Questions\n\n### Who was Harry Harlow and what was his primary area of research?\n\nHarry Harlow was a psychologist known for his research on dependency, social isolation, and maternal separation. His work laid the groundwork for entire fields of modern study in psychology.\n\n### What was the significance of Harlow's experiments on maternal attachment?\n\nHarlow's experiments demonstrated the importance of maternal comfort and security in the development of infants, challenging the prevailing wisdom of the time that suggested maternal attachment was purely transactional.\n\n### What were the Pit of Despair experiments?\n\nThe Pit of Despair experiments involved placing monkeys in isolation chambers to study the effects of social deprivation and depression. The monkeys were kept in complete isolation and darkness for extended periods, leading to severe psychological damage.\n\n### How did Harlow's work influence the field of psychology?\n\nHarlow's work led to significant changes in the understanding of maternal attachment and the importance of social interaction in development. It also played a crucial role in the establishment of ethical standards in psychological research.\n\n### What were the ethical controversies surrounding Harlow's research?\n\nHarlow's experiments were highly controversial due to the severe psychological and physical harm inflicted on the monkeys. His work sparked the animal liberation movement and led to stricter regulations on animal experimentation.\n\n### What was the Wisconsin General Testing Apparatus?\n\nThe Wisconsin General Testing Apparatus was a memory and cognition test developed by Harlow. It yielded interesting results, particularly in how primates developed strategies to solve the tests, leading Harlow to study 'learning to learn'.\n\n### What were the effects of social isolation on the monkeys in Harlow's studies?\n\nMonkeys subjected to social isolation exhibited behaviors such as pacing, dissociation, self-harm, and an inability to interact with other monkeys. Prolonged isolation led to severe and often irreversible psychological damage.\n\n### How did Harlow's personal experiences influence his research?\n\nHarlow's own struggles with depression and his distant relationship with his mother may have influenced his focus on maternal attachment and social isolation in his research.\n\n### What was the impact of Harlow's work on modern psychology?\n\nHarlow's findings on the importance of maternal attachment and social interaction have fundamentally changed practices in nurseries, social services, and maternity wards. His work also highlighted the need for ethical standards in psychological research.\n\n### What was the significance of Harlow's surrogate mother experiments?\n\nHarlow's surrogate mother experiments showed that infant monkeys preferred comfort and security over food, highlighting the importance of physical contact and emotional support in maternal relationships.\n\n## Sources\n\n- [Original Into the Shadows video: Harlow's Pit of Despair: Cruel, Shocking Psychological Research](https://www.youtube.com/watch?v=fu_36bljSIg)\n- [https://www.pbs.org/wgbh/aso/databank/entries/bhharl.html](https://www.pbs.org/wgbh/aso/databank/entries/bhharl.html)\n- [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC285801/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC285801/)\n- [https://www.wellbeingintlstudiesrepository.org/cgi/viewcontent.cgi?article=1112&context=acwp_arte](https://www.wellbeingintlstudiesrepository.org/cgi/viewcontent.cgi?article=1112&context=acwp_arte)\n- [https://www.iflscience.com/the-pit-of-despair-was-one-of-the-most-unethical-experiments-of-modern-science-60408](https://www.iflscience.com/the-pit-of-despair-was-one-of-the-most-unethical-experiments-of-modern-science-60408)\n- [https://onlinelibrary.wiley.com/doi/full/10.1002/jhbs.22180](https://onlinelibrary.wiley.com/doi/full/10.1002/jhbs.22180)\n- [https://pubmed.ncbi.nlm.nih.gov/35040491/](https://pubmed.ncbi.nlm.nih.gov/35040491/)\n- [https://archive.boston.com/news/globe/ideas/articles/2004/03/21/monkey_love/](https://archive.boston.com/news/globe/ideas/articles/2004/03/21/monkey_love/)\n- [https://link.springer.com/article/10.1007/s12124-008-9072-9](https://link.springer.com/article/10.1007/s12124-008-9072-9)\n- [https://www.psychologicalscience.org/publications/observer/obsonline/harlows-classic-studies-revealed-the-importance-of-maternal-contact.html](https://www.psychologicalscience.org/publications/observer/obsonline/harlows-classic-studies-revealed-the-importance-of-maternal-contact.html)\n- [https://pages.uoregon.edu/adoption/studies/HarlowMLE.htm](https://pages.uoregon.edu/adoption/studies/HarlowMLE.htm)\n- [https://allthatsinteresting.com/harry-harlow](https://allthatsinteresting.com/harry-harlow)\n- [https://www.nytimes.com/2003/02/02/books/no-more-wire-mothers-ever.html](https://www.nytimes.com/2003/02/02/books/no-more-wire-mothers-ever.html)\n- [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7433398/\\](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7433398/\\)\n- [https://link.springer.com/referenceworkentry/10.1007/978-3-319-55065-7_122](https://link.springer.com/referenceworkentry/10.1007/978-3-319-55065-7_122)\n- [https://journals.sagepub.com/doi/10.1177/0957154X10370909?icid=int.sj-full-text.similar-articles.1](https://journals.sagepub.com/doi/10.1177/0957154X10370909?icid=int.sj-full-text.similar-articles.1)\n- [https://psycnet.apa.org/record/2022-24880-001](https://psycnet.apa.org/record/2022-24880-001)\n- [https://www.britannica.com/biography/Lewis-Terman](https://www.britannica.com/biography/Lewis-Terman)\n- [Hero image source](https://upload.wikimedia.org/wikipedia/commons/b/b7/Fairfield_Warde_High_School%2C_2024.jpg) by Packer1028 / openverse, cc0.\n\n## Related Coverage" url: https://intotheshadows.pub/article/harlows-pit-of-despair-cruel-shocking-psychological-research.md canonical: https://intotheshadows.pub/article/harlows-pit-of-despair-cruel-shocking-psychological-research datePublished: 2026-06-28 dateModified: 2026-06-28 author: - name: Simon Whistler url: https://intotheshadows.pub/author/simon-whistler publisher: Into the Shadows image: "https://media.intotheshadows.pub/cdn-cgi/image/width=1600,height=900,fit=cover,quality=80,format=auto/articles/fu_36bljSIg/hero.jpg" type: Article contentHash: 3949dc3e16031fe6e562c0fd22c30b5765b514ede84e21b1af29fed9b6d30108 tokens: 8422 summaryUrl: https://intotheshadows.pub/article/harlows-pit-of-despair-cruel-shocking-psychological-research.md.summary.md --- Ask his students, and he might have been a visionary. Ask his contemporaries, and he might have been a mad scientist. Ask the experts of today, and he might have been a monster. Of all of the myriad pioneers of psychological research, there are few with a reputation quite so extreme as Dr. Harry F. Harlow, whose work on dependency, social isolation, and maternal separation laid the groundwork for entire fields of modern study—but did so at a shocking cost to his subjects, and in so doing, was one of the primary reasons why ethics in psychology are regarded with such critical importance today. In this article, we'll be digging into the demented scientific research of Harry Harlow: its cruel and unusual design, its critical revelations on the nature of interpersonal attachment, and the stunning degree to which Harlow's legacy has shaped the field of psychology today. ## The Man; The Question To understand the Harlow experiments, we've first got to understand the man who created them. Born Harry Frederick Israel in Fairfield, Iowa, in 1905, the boy who later became Harry Harlow is an enigma to modern-day biographers. Even today, we know little about his childhood years, except for excerpts from his own unfinished biography, suggesting a distant mother who modern theorists would describe—in part because of Harlow's own work—as avoidant or dismissive. Harlow also implied that he struggled with depression across his life, even in childhood. Although he was a smart boy, he was often bored by his surroundings, and even feared from a young age that he might eventually go insane. As a young adult, he made his way to Stanford University, gaining entry via a special aptitude test, but whatever his aptitude might have been, he struggled to express it in his early years as an English major. Beset with atrocious grades after just a semester, and clearly not showing a whole lot of promise in the field, Harlow was forced to look for other options. As his relief valve, he employed a tried-and-true tactic among struggling undergraduates of any generation: He became a psych major, and basically hoped for the best. Over the next six years, Harlow would earn first an undergraduate degree and then a doctorate at Stanford, spending most of his time studying directly under one Lewis Madison Terman. His mentor is remembered today for his drastic improvements on the Stanford-Binet Intelligence Scales—or, basically, the modern IQ test—and a long-term study he carried out, called the Genetic Studies of Genius, which was about…well, the genetic studies of genius. However, he was also very into eugenics at the same time that Harlow was studying under him. From what we can tell, Harlow didn't seem to adopt quite those same beliefs, but as we'll see shortly, there's more than one way to be a bit unhinged. Around this same time, he changed his name from Harry Israel to Harry Harlow; it was the early 1930s, and while Harlow himself wasn't Jewish, he feared that having a Jewish-sounding last name would bring on negative consequences in both his life and his career. The person behind that change, and the one who decided he was to be called Harlow? His mentor, Lewis Terman. From Stanford, Harlow made his way to the University of Wisconsin at Madison to become a professor. Without a laboratory on campus, and without any indication from the university that they intended to give him one, Harlow set up his own research space off-campus in what would later be named the Primate Laboratory. Harlow wasn't particularly interested in working with humans, and even though he was conducting his research in psychology's wild-west era when he probably could have gotten away with some pretty insane research designs, his particular research might have been a step too far for human-subjects research even before the introduction of modern research ethics. Harlow's early work at Madison was done via a local zoo, who supplied him with primates to engage with what he would eventually call the Wisconsin General Testing Apparatus. Basically a memory and cognition test, the Apparatus yielded some fairly interesting results for Harlow, but the most important one of all, wasn't actually one he had expected to find. Within a few tests of a given primate, Harlow realized that the primates were beginning to figure out strategies to get through the tests he was running. But although Harlow spent a while trying to figure out how the monkeys were developing those strategies—or, 'learning to learn', as he called it—that line of questioning ultimately became a gateway into the one that would make Harlow's entire career. You see, during the time that Harlow was running his first large-scale primate experiments, he decided to put together a breeding colony of monkeys in his lab. The primates he chose were rhesus macaques, an Old World monkey from southeast Asia with complex social groups, internal familial relationships, and close anatomical and physiological similarities to humans. During the establishment of the breeding colony, Harlow and his students were able to witness first-hand how healthy relationships between baby rhesus monkeys and their mothers developed, and when Harlow decided he wanted to rear the infant monkeys in a nursery rather than dealing with their protective mothers whenever he wanted to use one in an experiment, he began to notice something else. The nursery-raised macaques were coming out different—not physically, but behaviorally—and Harlow wanted to know why. Harlow and his contemporaries were living at a time in which infant attachment to their parents, especially their mothers, was not well-understood. Opinions on the impact of infant separation from a mother ran the gamut; some theorists postulated it had to do with a dependent, feeding relationship with a mother, purely transactional at first, while others contended that it barely mattered at all. Still others claimed that humans only organized into familial structures, and engaged with society, to gain steady access to sexual contact. Many famous or well-regarded psychologists of the era advised mothers and fathers not to even hold their children if it wasn't necessary, let alone to indulge their cries, for fear of spoiling them. As behaviorist John Watson once wrote, apparently without a hint of irony: "Do not overindulge them. Do not kiss them goodnight. Rather, give a brief bow and shake their hand before turning off the light." The American standard for nurseries at the time was to intentionally make them cold, distant, and inhospitable to positive attachment. But Harlow, along with a handful of other psychologists at the time, took a different tack. Depending on your perspective, you might say Harlow had a hunch. Or, you might say that he had more experience than most on the subject, after struggling to make sense of his own mother's behavior toward him as a boy. After all, that's the nature of every Freudian slip in psychology: saying one thing, and meaning your mother. But regardless, Harlow contended that an infant's bond with its mother mattered very, very much, and that it would have a profound impact on a child not just in infancy, but during the longer course of development as well. ## The Nature of Love Harlow's first really consequential experiment came over twenty years after he first began working at the University of Wisconsin, in 1957. By then, he had noticed the strangeness of some of his rhesus monkeys when they were raised away from their mothers, and he decided to run a longer and more organized study. He and his research team began separating infant monkeys from their mothers at birth, and raising them in what was essentially complete isolation other than their interactions with researchers. It seems obvious now, but at the time, it was a surprise for Harlow to learn that this impacted the monkeys severely. Left alone and deprived of stimulus, the monkeys learned to cope in all manner of ways: zoning out so hard they appeared to be doing what we now know to be dissociating, or pacing incessantly inside their cages, or even harming themselves. They proved incapable of interacting with other monkeys when they were eventually given the opportunity to do so, and some were so shaken by the experience that they stopped eating entirely, and starved to death. That was already a stunning finding, considering how starkly it ran contrary to the wisdom of the time. But Harlow had also picked up on one other detail: specifically, that the monkeys had shown a common behavior in clinging onto the diapers the research team had given them. Those diapers were made of cloth, they were soft, and the infant monkeys seemed to be taking comfort in them. That led Harlow toward the question of comfort in a maternal relationship—and the way he went about examining the nature of maternal comfort, would write his name into the history books. Harlow's next experiment exposed a new generation of infant monkeys to a pair of surrogate mothers…but not living ones. Each monkey involved in this study would be raised in an enclosure with two dummies, one made of cold, inflexible wire, and one made of soft cloth. In order to directly challenge his peers' contention that a mother-child relationship was all about accessing food, Harlow ensured that some monkeys would have their milk bottle stored in the cloth mother, while others had it stored in the wire mother. In all cases, no matter which of the surrogate mothers the monkeys had to use to get their milk, they nonetheless spent the vast majority of their time with the cloth mother. Monkeys that had a milk-giving wire mother would interact with it only minimally, and usually to feed; those that had a milk-giving cloth mother, ignored the wire mother entirely. But the real stunner came when those same monkeys were exposed to new environments, with new stimuli. When they were placed into those environments with the companionship of the cloth mother, they were curious, interactive, and at times even brave. When they were feeling less brave, they'd retreat back to the cloth mother or even the wire mother for safety. But when they were taken away from their surrogate mothers and placed into the same situations, they broke down, trying to hide, crying, and howling to return to safety. Of all the ways Harlow's experiment could have gone, there were few conceivable outcomes that might have screamed the conclusions at him any more conclusively. Harlow had also run experiments on infant monkeys that had grown up only with their mothers, and no peer exposure, and when those monkeys showed fear and aggressiveness when exposed to same-age peers, Harlow's takeaways grew stronger still in their conviction. The infant-mother relationship wasn't only about food, and in fact, it didn't even need food as a central component. Instead, it was all about comfort, safety, and security, feelings in which physical contact with the mother seemed to be absolutely critical. The implications for parents of that time were horrifying; after following the advice of the best psychologists of the day, they'd taken steps to raise their children in a way that, Harlow had now shown, was going to leave their children emotionally and developmentally stunted for the long term. His findings were confirmation to other theorists who'd been struggling to make the same point to the general public, and the idea of comfort as a cornerstone in child development really began to take on. It seems ridiculous to imagine now, but these were, at the time, truly groundbreaking ideas, and ones that shook the entire field of psychology to its core. ## Isolation and Deprivation With his grand thesis on the centrality of comfort now firmly interjected into American public consciousness, Harlow turned his attention back to his flock of rhesus monkeys. Now, the question at hand would be isolation. We've already mentioned the results of isolation that Harlow had observed in early experiments; that is, that infant monkeys raised without their mothers and without interaction with any other monkeys proved to be behaviorally strange compared to monkeys with normal upbringings. They would stare off into space for hours, harm themselves, and display all other manner of odd impulses in order to cope with their situation, and they proved utterly incapable of interacting with other monkeys after living in isolation for so long. Faced with those early results, Harlow did what any psychologist of the mid-20th century would have done: he looked at the situation he had created for his subjects, and endeavored to make it so much worse. In his subsequent studies, Harlow would expose infant monkeys to one of two conditions: partial social isolation, and complete social isolation. In the partial option, the monkeys would be barred from interacting with each other, kept in individual, bare wire cages set apart from each other, with no means to receive any level of physical comfort. But as it turns out, those monkeys had it easy. The total-deprivation group were raised in isolation chambers, from basically the moment of birth, for periods as long as a total of fifteen years in some cases, well over half of the average captive rhesus monkey's entire lifespan. The results were exactly what you might expect. In the totally isolated monkeys, the pacing came back, the dissociation came back, and the withdrawn, curled-up thumb-sucking behaviors, reported by Harlow as non-nutritional sucking, came back too. They became hostile toward any outside stimulus, including researchers, and showed hostility toward their own bodies as well. But the behaviors were at their worst, when these totally isolated monkeys were exposed to others for the first time. For this, we'll quote directly from Harlow, published in 1965: "No monkey has died during isolation. When initially removed from total social isolation, however, they usually go into a state of emotional shock, characterized by […] autistic self-clutching and rocking [….] One of six monkeys isolated for 3 months refused to eat after release and died 5 day later. The autopsy report attributed death to emotional anorexia. A second animal in the same group also refused to eat and probably would have died had we not been prepared to resort to forced feeding." In one particularly interesting detail, the emotional anorexia Harlow described appeared most strongly in infants that were isolated for just three months before being exposed to other monkeys. Infants who were isolated for longer periods, and matured a bit more in their solitude, certainly didn't enjoy their initial exposure to other monkeys, but the results were far less destructive. Harlow also noticed that when the monkeys, particularly the three-month isolates, were given the chance to spend more time with other monkeys around their age, they were able to come out of their shells and even rehabilitate themselves cognitively and socially. Said Harlow: "In human terms they are the children salvaged from the orphanage or inadequate home within the first year of life". The monkeys who'd been isolated for longer, however, showed severely impaired recovery, and were totally averse to contact play, or roughhousing, that would be common among normal macaques of the same age. In Harlow's writing: "The effects of 6 months of total social isolation were so devastating and debilitating that we had assumed initially that 12 months of isolation would not produce any additional decrement. This assumption proved to be false; 12 months of isolation almost obliterated the animals socially [….]". So stunted was the 12-month group's social growth that when it came time to have them interact with normally raised monkeys from a control group, quote, "the controls became increasingly aggressive toward the helpless isolate animals and might have killed them had we continued social testing". By the end of this run of studies, Harlow had concluded not only that a lack of social interaction could nearly entirely destroy an infant's capacity to function either at the present age or later in life, but that there was only a narrow, critical window for much of the damage to be undone. A three-month-old monkey could be taken out of isolation, placed into Harlow's rough equivalent of a nursery, and shown by their peers how to act, but the same couldn't be said for six-month-old or twelve-month-old monkeys. By Harlow's extrapolations, those were roughly the same developmental markers as a two-year-old child and a four-year-old child, respectively. And when those monkeys were left to interact only with peers that had also experienced the same isolation, they were able to interact only minimally, using the crude mechanisms they basically invented themselves. Those that eventually had children of their own were sometimes capable of not killing their own infants, but struggled to do anything more than that. But that news did come with one critical caveat: six-month-old monkeys who were placed into recovery groups not with normal six-month-old peers, but normal three-month-old peers, had a far better chance at a complete social recovery. ## The Pit of Despair Now, do you remember when we said earlier that Harlow, when faced by real and fascinating results on attachment, decided to do the mid-20th-century-psychologist thing and make life even more of a living hell for his subjects? Well, it was at this point in the final years of Harlow's career that he decided to repeat the cycle one more time. Harlow had always had a soft spot for choosing rather unconventional, or even sensationalist names for his own projects, including some that we're not going to mention because we'd rather not have this article taken down. But the one we do need to discuss, is a series of isolation chambers that Harlow referred to as the Pit of Despair. Harlow's intent with this round of studies was to attempt to build a model for understanding depression in animals, and if Harlow was going to do that, then he was going to need some depressed animals. To make that happen, he and his research partner at that time, Stephen Suomi, designed a stainless-steel trough that they technically termed a vertical chamber apparatus. Basically, it was a steel pit with a wire-mesh floor, a food box, and a water-bottle holder, with a top designed so that the monkeys inside couldn't use it to hang or entertain themselves. The sides of it were made to be slippery, sloping down to a narrow point where the monkey inside would barely have room to move. And this time, Harlow's subjects weren't infant monkeys removed from their mothers at birth. They were monkeys of an age at least three months old, who had already formed bonds with their mothers and their nursery playmates. Harlow's express intention was to shatter those bonds, and keep the monkeys in complete isolation and complete darkness for months. The result, of course, was precisely what you might expect. After a day or two spent attempting to escape, the monkeys inside would give up, descend to the bottom of the apparatus, curl up into a ball, and, by all outward appearances, languish in their despair with no opportunity to do anything else. As Harlow's collaborator Suomi wrote it later, no monkey was able to guard against the psychological anguish they seemed to experience inside the cage, and none of them emerged without sustaining serious psychological damage for the rest of their lives. After thirty days in the pit, monkeys who were released would refuse to interact with other monkeys, engage with any external stimuli, or even move of their own volition. For the most part, they would remain huddled and attempting to self-soothe by clutching at their own bodies. Those behaviors would persist for months in most cases, and they only got worse the longer a monkey had spent in the pit before release. Then, Harlow and his students would attempt to rehabilitate them, in efforts that were basically unsuccessful across the world. Harlow would insist in his later years that the studies had provided data that had major implications for the study of depression, but decades later, those same studies have been only minimally referenced in any work related to treatment. ## Controversies and Breakthroughs Harlow would die in Tucson, Arizona, at the age of 76 in 1981, by which time much of the public reaction to his work had already become firmly entrenched. With Harlow's publications, and the slow evolution of his work from the genuinely groundbreaking to the increasingly macabre, his name had become the source of powerful controversies within the scientific community, and controversies that would only grow more and more intense after the end of his life. Now, before we get into the many, many, many negatives of Harlow's work, we do need to take a moment and acknowledge the real value of what he achieved. Harlow's work on the importance of maternal attachment came at a time when it was desperately needed, and when conventional wisdom suggested that children were best left stranded in social and parental isolation. Harlow's work clearly demonstrated, and later studies have since confirmed, that such treatment of children—whether monkey or human—would seriously stunt a child's ability to grow, erase critical social skills, and have an impact that would echo throughout the rest of their lives. For his work, Harlow won national acclaim in the United States, and he was even named president of the APA, or American Psychological Association, which governs academics across the entire field of psychological research. But Harlow's work also made him one of a few members of one of modern psychology's most exclusive clubs: the researchers whose work inspired the creation of ethical standards in human and animal psychological research, not because of the lessons Harlow's research taught anybody, but to ensure that research like it could never take place again. One of Harlow's own former students, University of Washington professor Gene Sackett, has since explained how Harlow's experiments basically kicked off the animal liberation movement in the US, and forced America to reckon with the treatment of animals in laboratory settings. Today, the use of lab animals is tightly regulated by the APA and other governing bodies, who refuse to sponsor, endorse, or even allow the use of research institutions for human or animal experimentation that is deemed to have too great of a risk of harm to its subjects. When it comes to educating the next generation of psychologists, Harlow's example, and the sheer visceral horror it evokes in people who learn about it, have made it a flagship case of what not to do. Ask a first-year undergraduate psychology student at any American university, fresh off an introductory class, and they may or may not be able to explain the mechanisms of interpersonal attachment or the models that guide our understanding of human or animal depression. But they sure as hell know Harlow's monkeys, and can probably recount a detailed explanation from their professors or teaching assistants on just why research like that is such a bad idea. Harlow's personal reputation hasn't survived, either, and it's not as if he helped his own case in trying to preserve it. In his later years, he would reveal to interviewers and students his disdain for the monkeys he'd used as subjects, including with this gem of a quote from 1974: "The only thing I care about is whether the monkeys will turn out a property I can publish. I don't have any love for them. Never have. I really don't like animals. I despise cats, I hate dogs. How could you like a monkey?" Routinely, Harlow would attempt to frame any disputes around the welfare of his animals as a matter of public relations or perception, and would dismiss any genuine care for the animals shown by his many critics, as either being misguided or fabricating their concern outright. As another of his former students said later in life, despite himself continuing deprivation experiments with animal subjects, quote, "it's as if he sat down and said, 'I'm only going to be around another ten years. What I'd like to do, then, is leave a great big mess behind.' If that was his aim, he did a perfect job." Not only that, but Harlow's own motivations for conducting some of his most questionable studies has been repeatedly called into question. As we alluded to before, this was a man who devoted his life to studying mother-child attachment, and often ripping away that attachment from his subjects, after having been deprived of such attachment himself. There were side experiments we didn't even mention before, including the use of a surrogate-mother machine that attacked baby monkeys with spikes or cold air to simulate real-life abuse. The results, by the way, showed that those baby monkeys were still unable to bring themselves to stop seeking comfort from the evil, but cloth-covered abusive surrogates. Harlow's later Pit of Despair experiments came at a time in his life when Harlow himself entered a well of despair, following the death of his second wife after a long battle with cancer. With his own personal depression came disinterest in attachment, and far more of an interest in the isolation of his subjects. When asked by another faculty member at the University of Wisconsin why on Earth Harlow was using these demented pits for his research, Harlow reportedly responded, "Because that's how it feels when you're depressed." One of his former doctoral students he'd worked with during the Pit of Despair years has since explained that he had to be talked out of an even more descriptive name, the Dungeon of Despair, for fears of how the university and Harlow's own peers might react. Other critics pointed out that the Pit of Despair research was generating results that might have been shocking in the 1950s—for example, the idea that living organisms might experience negative effects because of social deprivation—but were well-understood by the time those later experiments actually took place. Said writer Wayne Booth, "Harry Harlow and his colleagues go on torturing their nonhuman primates decade after decade, invariably proving what we all knew in advance—that social creatures can be destroyed by destroying their social ties". In retrospect, it's impossible to dismiss the life and work of Harry Harlow in its entirety. Modern nurseries, social services, maternity wards, and countless individual relationships between mothers, fathers, and their children have been fundamentally changed for the better because of what Harlow was able to show the world with his studies. But at the same time, Harlow left behind a long and indisputable legacy of intense pain and even depravity in the name of science. Harlow and his work did, indeed, represent progress, but at a price of decades of unyielding cruelty. He was a man one part visionary, one part mad scientist, and one part pure madman. The world wouldn't be the same without him, and yet, it is imperative that the field of psychology never hosts a figure quite like him again. ## Key Takeaways - Harry Harlow's experiments on maternal separation and social isolation in monkeys were pivotal in understanding the importance of maternal attachment. - Harlow's work demonstrated that comfort, safety, and security are crucial for infant development, challenging prevailing beliefs. - The ethical implications of Harlow's research led to significant changes in psychological research standards, emphasizing the protection of subjects. - Harlow's controversial methods, including the Pit of Despair, highlighted the severe psychological damage caused by social deprivation. - Despite his groundbreaking contributions, Harlow's legacy is marred by the extreme cruelty inflicted on his animal subjects. ## Frequently Asked Questions ### Who was Harry Harlow and what was his primary area of research? Harry Harlow was a psychologist known for his research on dependency, social isolation, and maternal separation. His work laid the groundwork for entire fields of modern study in psychology. ### What was the significance of Harlow's experiments on maternal attachment? Harlow's experiments demonstrated the importance of maternal comfort and security in the development of infants, challenging the prevailing wisdom of the time that suggested maternal attachment was purely transactional. ### What were the Pit of Despair experiments? The Pit of Despair experiments involved placing monkeys in isolation chambers to study the effects of social deprivation and depression. The monkeys were kept in complete isolation and darkness for extended periods, leading to severe psychological damage. ### How did Harlow's work influence the field of psychology? Harlow's work led to significant changes in the understanding of maternal attachment and the importance of social interaction in development. It also played a crucial role in the establishment of ethical standards in psychological research. ### What were the ethical controversies surrounding Harlow's research? Harlow's experiments were highly controversial due to the severe psychological and physical harm inflicted on the monkeys. His work sparked the animal liberation movement and led to stricter regulations on animal experimentation. ### What was the Wisconsin General Testing Apparatus? The Wisconsin General Testing Apparatus was a memory and cognition test developed by Harlow. It yielded interesting results, particularly in how primates developed strategies to solve the tests, leading Harlow to study 'learning to learn'. ### What were the effects of social isolation on the monkeys in Harlow's studies? Monkeys subjected to social isolation exhibited behaviors such as pacing, dissociation, self-harm, and an inability to interact with other monkeys. Prolonged isolation led to severe and often irreversible psychological damage. ### How did Harlow's personal experiences influence his research? Harlow's own struggles with depression and his distant relationship with his mother may have influenced his focus on maternal attachment and social isolation in his research. ### What was the impact of Harlow's work on modern psychology? Harlow's findings on the importance of maternal attachment and social interaction have fundamentally changed practices in nurseries, social services, and maternity wards. His work also highlighted the need for ethical standards in psychological research. ### What was the significance of Harlow's surrogate mother experiments? Harlow's surrogate mother experiments showed that infant monkeys preferred comfort and security over food, highlighting the importance of physical contact and emotional support in maternal relationships. ## Sources - [Original Into the Shadows video: Harlow's Pit of Despair: Cruel, Shocking Psychological Research](https://www.youtube.com/watch?v=fu_36bljSIg) - [https://www.pbs.org/wgbh/aso/databank/entries/bhharl.html](https://www.pbs.org/wgbh/aso/databank/entries/bhharl.html) - [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC285801/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC285801/) - [https://www.wellbeingintlstudiesrepository.org/cgi/viewcontent.cgi?article=1112&context=acwp_arte](https://www.wellbeingintlstudiesrepository.org/cgi/viewcontent.cgi?article=1112&context=acwp_arte) - [https://www.iflscience.com/the-pit-of-despair-was-one-of-the-most-unethical-experiments-of-modern-science-60408](https://www.iflscience.com/the-pit-of-despair-was-one-of-the-most-unethical-experiments-of-modern-science-60408) - [https://onlinelibrary.wiley.com/doi/full/10.1002/jhbs.22180](https://onlinelibrary.wiley.com/doi/full/10.1002/jhbs.22180) - [https://pubmed.ncbi.nlm.nih.gov/35040491/](https://pubmed.ncbi.nlm.nih.gov/35040491/) - [https://archive.boston.com/news/globe/ideas/articles/2004/03/21/monkey_love/](https://archive.boston.com/news/globe/ideas/articles/2004/03/21/monkey_love/) - [https://link.springer.com/article/10.1007/s12124-008-9072-9](https://link.springer.com/article/10.1007/s12124-008-9072-9) - [https://www.psychologicalscience.org/publications/observer/obsonline/harlows-classic-studies-revealed-the-importance-of-maternal-contact.html](https://www.psychologicalscience.org/publications/observer/obsonline/harlows-classic-studies-revealed-the-importance-of-maternal-contact.html) - [https://pages.uoregon.edu/adoption/studies/HarlowMLE.htm](https://pages.uoregon.edu/adoption/studies/HarlowMLE.htm) - [https://allthatsinteresting.com/harry-harlow](https://allthatsinteresting.com/harry-harlow) - [https://www.nytimes.com/2003/02/02/books/no-more-wire-mothers-ever.html](https://www.nytimes.com/2003/02/02/books/no-more-wire-mothers-ever.html) - [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7433398/\](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7433398/\) - [https://link.springer.com/referenceworkentry/10.1007/978-3-319-55065-7_122](https://link.springer.com/referenceworkentry/10.1007/978-3-319-55065-7_122) - [https://journals.sagepub.com/doi/10.1177/0957154X10370909?icid=int.sj-full-text.similar-articles.1](https://journals.sagepub.com/doi/10.1177/0957154X10370909?icid=int.sj-full-text.similar-articles.1) - [https://psycnet.apa.org/record/2022-24880-001](https://psycnet.apa.org/record/2022-24880-001) - [https://www.britannica.com/biography/Lewis-Terman](https://www.britannica.com/biography/Lewis-Terman) - [Hero image source](https://upload.wikimedia.org/wikipedia/commons/b/b7/Fairfield_Warde_High_School%2C_2024.jpg) by Packer1028 / openverse, cc0. ## Related Coverage