baby and monkey experiment

This Guy Simultaneously Raised a Chimp and a Baby in Exactly the Same Way to See What Would Happen

When treated as a human, the baby chimp acted like one—until her physiology and development held her back

Rachel Nuwer

On June 26, 1931, comparative psychologist Winthrop Niles Kellogg and his wife welcomed a new arrival home: not a human infant, but a baby chimpanzee. The couple planned to raise the chimp, Gua, alongside their own baby boy, Donald. As later described in the  Psychological Record , the idea was to see how environment influenced development. Could a chimp grow up to behave like a human? Or even think it was a human? 

Since his student days, Kellogg had dreamed of conducting such an experiment. He was fascinated by wild children, or those raised with no human contact, often in nature. Abandoning a human child in the wilderness would be ethically reprehensible, Kellogg knew, so he opted to experiment on the reverse scenario—bringing an infant animal into civilization. 

For the next nine months, for 12 hours a day and seven days a week, Kellogg and his wife conducted tireless tests on Donald and Gua.

They raised the two babies in exactly the same way, in addition to conducting an exhaustive list of scientific experiments that included subjects such as "blood pressure, memory, body size, scribbling, reflexes, depth perception, vocalization, locomotion, reactions to tickling, strength, manual dexterity, problem solving, fears, equilibrium, play behavior, climbing, obedience, grasping, language comprehension, attention span and others," the  Psychological Record authors note.

For a while, Gua actually excelled at these tests compared to Donald.

But eventually,  as  NPR notes , Gua hit a cognitive wall: No amount of training or nurturing could overcome the fact that, genetically, she was a chimpanzee. As such, the Psychological Record  authors write, the Kelloggs' experiment "probably succeeded better than any study before its time in demonstrating the limitations heredity placed on an organism regardless of environmental opportunities as well as the developmental gains that could be made in enriched environments."

The experiment, however, ended rather abruptly and mysteriously. As the Psychological Record  authors describe: 

Our final concern is why the project ended when it did. We are told only that the study was terminated on March 28, 1932, when Gua was returned to the Orange Park primate colony through a gradual rehabilitating process. But as for why, the Kelloggs, who are so specific on so many other points, leave the reader wondering. 

It could be that the Kelloggs were simply exhausted from nine months of nonstop parenting and scientific work. Or perhaps it was the fact that Gua was becoming stronger and less manageable, and that the Kelloggs feared she might harm her human brother. Finally, one other possibility comes to mind, the authors point out: While Gua showed no signs of learning human languages, her brother Donald had begun imitating Gua's chimp noises. "In short, the language retardation in Donald may have brought an end to the study," the authors write.

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Rachel Nuwer is a freelance science writer based in Brooklyn.

Harry Harlow Theory & Rhesus Monkey Experiments in Psychology

Saul McLeod, PhD

Editor-in-Chief for Simply Psychology

BSc (Hons) Psychology, MRes, PhD, University of Manchester

Saul McLeod, PhD., is a qualified psychology teacher with over 18 years of experience in further and higher education. He has been published in peer-reviewed journals, including the Journal of Clinical Psychology.

Learn about our Editorial Process

Olivia Guy-Evans, MSc

Associate Editor for Simply Psychology

BSc (Hons) Psychology, MSc Psychology of Education

Olivia Guy-Evans is a writer and associate editor for Simply Psychology. She has previously worked in healthcare and educational sectors.

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Harlow (1958 wanted to study the mechanisms by which newborn rhesus monkeys bond with their mothers.

These infants depended highly on their mothers for nutrition, protection, comfort, and socialization.  What, exactly, though, was the basis of the bond?

The learning theory of attachment suggests that an infant would form an attachment with a carer who provides food. In contrast, Harlow explained that attachment develops due to the mother providing “tactile comfort,” suggesting that infants have an innate (biological) need to touch and cling to something for emotional comfort.

Harry Harlow did a number of studies on attachment in rhesus monkeys during the 1950’s and 1960″s.  His experiments took several forms:

Cloth Mother vs. Wire Mother Experiment

Experiment 1.

Harlow (1958) separated infant monkeys from their mothers immediately after birth and placed in cages with access to two surrogate mothers, one made of wire and one covered in soft terry toweling cloth.

In the first group, the terrycloth mother provided no food, while the wire mother did, in the form of an attached baby bottle containing milk.

Both groups of monkeys spent more time with the cloth mother (even if she had no milk).  The infant would only go to the wire mother when hungry. Once fed it would return to the cloth mother for most of the day.  If a frightening object was placed in the cage the infant took refuge with the cloth mother (its safe base).

This surrogate was more effective in decreasing the youngster’s fear.  The infant would explore more when the cloth mother was present.

This supports the evolutionary theory of attachment , in that the sensitive response and security of the caregiver are important (as opposed to the provision of food).

Experiment 2

Harlow (1958) modified his experiment and separated the infants into two groups: the terrycloth mother which provided no food, or the wire mother which did.

All the monkeys drank equal amounts and grew physically at the same rate. But the similarities ended there. Monkeys who had soft, tactile contact with their terry cloth mothers behaved quite differently than monkeys whose mothers were made out of hard wire.

The behavioral differences that Harlow observed between the monkeys who had grown up with surrogate mothers and those with normal mothers were;

• They were much more timid.
• They didn’t know how to act with other monkeys.
• They were easily bullied and wouldn’t stand up for themselves.
• They had difficulty with mating.
• The females were inadequate mothers.

These behaviors were observed only in the monkeys left with the surrogate mothers for more than 90 days.

For those left less than 90 days, the effects could be reversed if placed in a normal environment where they could form attachments.

Rhesus Monkeys Reared in Isolation

Harlow (1965) took babies and isolated them from birth. They had no contact with each other or anybody else.

He kept some this way for three months, some for six, some for nine and some for the first year of their lives. He then put them back with other monkeys to see what effect their failure to form attachment had on behavior.

The results showed the monkeys engaged in bizarre behavior, such as clutching their own bodies and rocking compulsively. They were then placed back in the company of other monkeys.

To start with the babies were scared of the other monkeys, and then became very aggressive towards them. They were also unable to communicate or socialize with other monkeys. The other monkeys bullied them. They indulged in self-mutilation, tearing hair out, scratching, and biting their own arms and legs.<!–

In addition, Harlow created a state of anxiety in female monkeys which had implications once they became parents. Such monkeys became so neurotic that they smashed their infant’s face into the floor and rubbed it back and forth.

Harlow concluded that privation (i.e., never forming an attachment bond) is permanently damaging (to monkeys).

The extent of the abnormal behavior reflected the length of the isolation. Those kept in isolation for three months were the least affected, but those in isolation for a year never recovered from the effects of privation.

Conclusions

Studies of monkeys raised with artificial mothers suggest that mother-infant emotional bonds result primarily from mothers providing infants with comfort and tactile contact, rather than just fulfilling basic needs like food.

Harlow concluded that for a monkey to develop normally s/he must have some interaction with an object to which they can cling during the first months of life (critical period).

Clinging is a natural response – in times of stress the monkey runs to the object to which it normally clings as if the clinging decreases the stress.

He also concluded that early maternal deprivation leads to emotional damage but that its impact could be reversed in monkeys if an attachment was made before the end of the critical period .

However, if maternal deprivation lasted after the end of the critical period, then no amount of exposure to mothers or peers could alter the emotional damage that had already occurred.

Harlow found, therefore, that it was social deprivation rather than maternal deprivation that the young monkeys were suffering from.

When he brought some other infant monkeys up on their own, but with 20 minutes a day in a playroom with three other monkeys, he found they grew up to be quite normal emotionally and socially.

The Impact of Harlow’s Research

Harlow’s research has helped social workers to understand risk factors in child neglect and abuse such as a lack of comfort (and so intervene to prevent it).

Using animals to study attachment can benefit children who are most at risk in society and can also have later economic implications, as those children are more likely to grow up to be productive members of society.

Ethics of Harlow’s Study

Harlow’s work has been criticized.  His experiments have been seen as unnecessarily cruel (unethical) and of limited value in attempting to understand the effects of deprivation on human infants.

It was clear that the monkeys in this study suffered from emotional harm from being reared in isolation.  This was evident when the monkeys were placed with a normal monkey (reared by a mother), they sat huddled in a corner in a state of persistent fear and depression.

Harlow’s experiment is sometimes justified as providing a valuable insight into the development of attachment and social behavior. At the time of the research, there was a dominant belief that attachment was related to physical (i.e., food) rather than emotional care.

It could be argued that the benefits of the research outweigh the costs (the suffering of the animals).  For example, the research influenced the theoretical work of John Bowlby , the most important psychologist in attachment theory.

It could also be seen as vital in convincing people about the importance of emotional care in hospitals, children’s homes, and daycare.

Harlow, H. F., Dodsworth, R. O., & Harlow, M. K. (1965). Total social isolation in monkeys . Proceedings of the National Academy of Sciences of the United States of America, 54 (1), 90.

Harlow, H. F. & Zimmermann, R. R. (1958). The development of affective responsiveness in infant monkeys . Proceedings of the American Philosophical Society, 102 ,501 -509.

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Harry Harlow and the Nature of Affection

What Harlow's Infamous Monkey Mother Experiments Revealed

• Love and Affection
• Harry Harlow's Research on Love
• Wire Mother Experiment
• Fear and Security

Impact of Harry Harlow’s Research

Frequently asked questions.

Harry Harlow was one of the first psychologists to scientifically investigate the nature of human love and affection. Through a series of controversial monkey mother experiments, Harlow was able to demonstrate the importance of early attachments, affection, and emotional bonds in the course of healthy development.

This article discusses his famous monkey mother experiments and what the results revealed. It also explores why Harlow's monkey experiments are so unethical and controversial.

Early Research On Love

During the first half of the 20th century, many psychologists believed that showing affection towards children was merely a sentimental gesture that served no real purpose. According to many thinkers of the day, affection would only spread diseases and lead to adult psychological problems.

"When you are tempted to pet your child, remember that mother love is a dangerous instrument," the behaviorist John B. Watson once even went so far as to warn parents.

Psychologists were motivated to prove their field as a rigorous science. The behaviorist movement dominated the field of psychology during this time. This approach urged researchers to study only observable and measurable behaviors.

An American psychologist named Harry Harlow , however, became interested in studying a topic that was not so easy to quantify and measure—love. In a series of controversial experiments conducted during the 1960s, Harlow demonstrated the powerful effects of love and in particular, the absence of love.   

His work demonstrated the devastating effects of deprivation on young rhesus monkeys. Harlow's research revealed the importance of a caregiver's love for healthy childhood development.

Harlow's experiments were often unethical and shockingly cruel , yet they uncovered fundamental truths that have influenced our understanding of child development.

Harry Harlow's Research on Love

Harlow noted that very little attention had been devoted to the experimental research of love. At the time, most observations were largely philosophical and anecdotal.

"Because of the dearth of experimentation, theories about the fundamental nature of affection have evolved at the level of observation, intuition, and discerning guesswork, whether these have been proposed by psychologists, sociologists, anthropologists, physicians, or psychoanalysts ," he noted.

Many of the existing theories of love centered on the idea that the earliest attachment between a mother and child was merely a means for the child to obtain food, relieve thirst, and avoid pain. Harlow, however, believed that this behavioral view of mother-child attachments was an inadequate explanation.

The Monkey Mother Experiment

His most famous experiment involved giving young rhesus monkeys a choice between two different "mothers." One was made of soft terrycloth but provided no food. The other was made of wire but provided nourishment from an attached baby bottle.

Harlow removed young monkeys from their natural mothers a few hours after birth and left them to be "raised" by these mother surrogates. The experiment demonstrated that the baby monkeys spent significantly more time with their cloth mother than with their wire mother.

In other words, the infant monkeys went to the wire mother only for food but preferred to spend their time with the soft, comforting cloth mother when they were not eating.

Based on these findings, Harry Harlow concluded that affection was the primary force behind the need for closeness.

Harry Harlow's Further Research

Later research demonstrated that young monkeys would also turn to their cloth surrogate mother for comfort and security. Such work revealed that affectionate bonds were critical for development.

Harlow utilized a "strange situation" technique similar to the one created by attachment researcher Mary Ainsworth . Young monkeys were allowed to explore a room either in the presence of their surrogate mother or in her absence.

Monkeys who were with their cloth mother would use her as a secure base to explore the room. When the surrogate mothers were removed from the room, the effects were dramatic. The young monkeys no longer had their secure base for exploration and would often freeze up, crouch, rock, scream, and cry.

Harry Harlow’s experiments offered irrefutable proof that love is vital for normal childhood development . Additional experiments by Harlow revealed the long-term devastation caused by deprivation, leading to profound psychological and emotional distress and even death.

Harlow’s work, as well as important research by psychologists John Bowlby and Mary Ainsworth, helped influence key changes in how orphanages, adoption agencies, social services groups, and childcare providers approached the care of children.

Harlow's work led to acclaim and generated a wealth of research on love, affection, and interpersonal relationships. However, his own personal life was marked by conflict.

After the terminal illness of his wife, he became engulfed by alcohol misuse and depression, eventually becoming estranged from his own children. Colleagues frequently described him as sarcastic, mean-spirited, misanthropic, chauvinistic, and cruel.

While he was treated for depression and eventually returned to work, his interests shifted following the death of his wife. He no longer focused on maternal attachment and instead developed an interest in depression and isolation.

Despite the turmoil that marked his later personal life, Harlow's enduring legacy reinforced the importance of emotional support, affection, and love in the development of children.

A Word From Verywell

Harry Harlow's work was controversial in his own time and continues to draw criticism today. While such experiments present major ethical dilemmas, his work helped inspire a shift in the way that we think about children and development and helped researchers better understand both the nature and importance of love.

Harlow's research demonstrated the importance of love and affection, specifically contact comfort, for healthy childhood development. His research demonstrated that children become attached to caregivers that provide warmth and love, and that this love is not simply based on providing nourishment. 

Harlow's monkey mother experiment was unethical because of the treatment of the infant monkeys. The original monkey mother experiments were unnecessarily cruel. The infant monkeys were deprived of maternal care and social contact.

In later experiments, Harlow kept monkeys in total isolation in what he himself dubbed a "pit of despair." While the experiments provided insight into the importance of comfort contact for early childhood development, the research was cruel and unethical.

Hu TY, Li J, Jia H, Xie X. Helping others, warming yourself: altruistic behaviors increase warmth feelings of the ambient environment . Front Psychol . 2016;7:1349. doi:10.3389/fpsyg.2016.01349

Suomi SJ. Risk, resilience, and gene-environment interplay in primates . J Can Acad Child Adolesc Psychiatry . 2011;20(4):289-297.

Zhang B. Consequences of early adverse rearing experience(EARE) on development: insights from non-human primate studies . Zool Res . 2017;38(1):7-35. doi:10.13918/j.issn.2095-8137.2017.002

Harlow HF. The nature of love .  American Psychologist. 1958;13(12):673-685. doi:10.1037/h0047884

Hong YR, Park JS. Impact of attachment, temperament and parenting on human development . Korean J Pediatr . 2012;55(12):449-454. doi:10.3345/kjp.2012.55.12.449

Blum D. Love at Goon Park . New York: Perseus Publishing; 2011.

Ottaviani J, Meconis D. Wire Mothers: Harry Harlow and the Science of Love . Ann Arbor, MI: G.T. Labs; 2007.

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

Harlow’s Classic Studies Revealed the Importance of Maternal Contact

• Child Development
• Cognitive Psychology
• Infant Development
• Social Interaction
• Social Isolation
• Social Psychology

Harry Harlow’s empirical work with primates is now considered a “classic” in behavioral science, revolutionizing our understanding of the role that social relationships play in early development. In the 1950s and 60s, psychological research in the United States was dominated by behaviorists and psychoanalysts, who supported the view that babies became attached to their mothers because they provided food. Harlow and other social and cognitive psychologists argued that this perspective overlooked the importance of comfort, companionship, and love in promoting healthy development.

Using methods of isolation and maternal deprivation, Harlow showed the impact of contact comfort on primate development. Infant rhesus monkeys were taken away from their mothers and raised in a laboratory setting, with some infants placed in separate cages away from peers. In social isolation, the monkeys showed disturbed behavior, staring blankly, circling their cages, and engaging in self-mutilation. When the isolated infants were re-introduced to the group, they were unsure of how to interact — many stayed separate from the group, and some even died after refusing to eat.

Even without complete isolation, the infant monkeys raised without mothers developed social deficits, showing reclusive tendencies and clinging to their cloth diapers. Harlow was interested in the infants’ attachment to the cloth diapers, speculating that the soft material may simulate the comfort provided by a mother’s touch. Based on this observation, Harlow designed his now-famous surrogate mother experiment.

In this study, Harlow took infant monkeys from their biological mothers and gave them two inanimate surrogate mothers: one was a simple construction of wire and wood, and the second was covered in foam rubber and soft terry cloth. The infants were assigned to one of two conditions. In the first, the wire mother had a milk bottle and the cloth mother did not; in the second, the cloth mother had the food while the wire mother had none.

In both conditions, Harlow found that the infant monkeys spent significantly more time with the terry cloth mother than they did with the wire mother. When only the wire mother had food, the babies came to the wire mother to feed and immediately returned to cling to the cloth surrogate.

Harlow’s work showed that infants also turned to inanimate surrogate mothers for comfort when they were faced with new and scary situations. When placed in a novel environment with a surrogate mother, infant monkeys would explore the area, run back to the surrogate mother when startled, and then venture out to explore again. Without a surrogate mother, the infants were paralyzed with fear, huddled in a ball sucking their thumbs. If an alarming noise-making toy was placed in the cage, an infant with a surrogate mother present would explore and attack the toy; without a surrogate mother, the infant would cower in fear.

Together, these studies produced groundbreaking empirical evidence for the primacy of the parent-child attachment relationship and the importance of maternal touch in infant development. More than 70 years later, Harlow’s discoveries continue to inform the scientific understanding of the fundamental building blocks of human behavior.

Harlow H. F., Dodsworth R. O., & Harlow M. K. (1965). Total social isolation in monkeys. Proceedings of the National Academy of Sciences of the United States of America. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC285801/pdf/pnas00159-0105.pdf

Suomi, S. J., & Leroy, H. A. (1982). In memoriam: Harry F. Harlow (1905–1981). American Journal of Primatology, 2 , 319–342. doi:10.1002/ajp.1350020402

Tavris, C. A. (2014). Teaching contentious classics. The Association for Psychological Science . Retrieved from https://www.psychologicalscience.org/observer/teaching-contentious-classics

Loved the simplicity of article but wanted to Apa cite it but didn’t see a name who wrote it

typed a partial comment and was disrupted and never got around to sending it. I tried to relocate it on my computer, but was not able. Could have been my thoughts. As a substitute teacher I see the results of giving a child a phone rather than giving a child love and all that goes with it. I see the predictions of Harry Harlow have come to pass. No absolutes, no positive examples, no investment of time, just looking for the allusive moment of quality time, that requires an investment TIME to be there for that moment in time. Any way I’m probably not the one you’re looking for.

The above summary fails to address any critique of Harlow’s legacy. Nothing about use of Harlow’s “pit of despair,” or his “rape rack” to use his own term? Nothing about beginning “his harsher isolation and depression experiments while “corrosively depressed” and “stumbling around drunk”? No concern about any possibility of sadism as “science”? No question of “how much suffering is justified by the imperatives of science”? For starters, see S. Hansen’s 11/13/2002 salon.com review of Deborah Blum’s Love at Goon Park, or the essay on Harlow in psychologist Loren Slater’s book, Opening Skinner’s Box.

Gigi, the sole reason for the experiment was not to root out sadism, it was to explain the need for attachment. Sorry about the special feelings you have for animals. It is a good point you let us see, you can now use that opportunity to show us sadism in regards to the research they made. I will search that article you point out to see what that author had to say about sadism.

I read these these experiments when they were published in the Scientific American journals.

I find he article a good review of the original work.

I worked in Harlow’s lab as as an undergraduate student in 1951/52. What I learned from this experience is the value of facts and verified statements about animal behavior. As a 20 year old kid discharged from the army, I was severely reprimanded for stating that a monkey had bit me in anger when I slapped its paw for trying to steal reasons out of lab coat. I was bitten but I invented the reason. Our work was to flesh out the phylo-genetic scale. Along with just learning studies, with white rats as well.

And what did you discover?

Wow that’s amazing you worked in the lab, I think so just starting out in psychology and my first lesson was Harlow. It’s was very interesting learning about him, my only thought was the monkeys have to admit but that was done in those days. Thanks Sue

I agree that in this day and age, we would criticize this treatment. I have no doubt much of it still goes on, people still eat animals. That was a different time, we learn from the past so that we do not repeat it. But to be angry about the past or that someone could find the good research that was deemed from it is histrionic and a waste of positive energy.

Are you people insane? “I agree that in this day and age, we would criticize this treatment” I was raised in exactly in accord with Harlow’s experiments, denied human contact almost since birth. And you APPROVE of this?! “That was a different time, we learn from the past so that we do not repeat it.” Oh, you know so little. Look up “secure confinement” and consider what children face every day of their lives.

I agree with Harry’s theory.

I also find it sadistic or at least totally lacking in sensitivity and compassion to have torn these baby monkeys from their mothers to learn what.That they prefer warmth to a hard screen even when food is involved? It is this kind of thinking that leads to the willingness of politicians to separate families, putting children in cages so that they will be less likely to come to America for help. Truly sadistic!

I think we need like a chat forum for discussion about these issues honestly. I’d love to debate about this stuff actually and am wondering whether any means is sufficient. In regards to the actual experiment, Im not going to get my beliefs on ethical treatment mixed up and it did produce significant findings. I’m more upset about the actual findings themselves. It could also be because I see some very loose correlation between them and my life unfortunately. The published paper was definitely worth the read and I wish I didn’t.

I think the whole point is that the experiments show why politicians should NOT separate families etc.. it’s difficult to prove the effects of cruelty without being cruel. The alarming thing is how little has been learned from the sacrifice. I know a young woman with learning difficulties, abandonment issues and probable RAD who is in care. She has created a fantasy world with cuddly toys. She is chastised for this by her ‘carers’ who confiscate them and make her feel guilty about her self. I am currently composing a letter for social services to intervene. I intend enclosing the above article. Everyone who works in care should be made to read it!

I studied psychology as an undergrad several years ago, and of the cognitive development experiments that made it into academic text, Harlow’s was one that has always stuck in my mind. To refer to the outcomes and substantiated findings of studies such as these, without acknowledging the cruelty perpetuated in carrying them out, might be impossible. The two go hand in hand, and that’s the point. But years later, can we say the ends justified the means? Yes…and no. Studies such as this one, were done years ago, perhaps in a time with very different regulations; however, the findings are none the less very substantial. And, I personally believe could, and should, be referred to in the training of a variety of service and caregiver professions, as this last comment suggests. There is still much to be learned in Behavioral science area of study, but as a society in need of great change as a whole, we should be working to figure out how we can capitalize on the knowledge gained from past studies such as this one…as opposed to focusing solely on the conditions in which they were done in. That’s not to allow our emotions to diminish the importance of the findings, without putting them to good use in our everyday lives. The end goal being to make a positive difference in society moving forward.

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Harlow’s Monkey Experiments: 3 Findings About Attachment

When that need is met, the infant develops a secure attachment style; however, when that need is not met, the infant can develop an attachment disorder.

In this post, we’ll briefly explore attachment theory by looking at Harlow’s monkey experiments and how those findings relate to human behavior and attachment styles. We’ll also look at some of the broader research that resulted from Harlow’s experiments.

Before we begin, I have to warn you that Harlow’s experiments are distressing and can be upsetting. Nowadays, his experiments are considered unethical and would most likely not satisfy the requirements of an ethical board. However, knowing this, the findings of his research do provide insight into the important mammalian bond that exists between infant and parent.

Before you continue, we thought you might like to download our three Positive Relationships Exercises for free . These detailed, science-based exercises will help you or your clients build healthy, life-enriching relationships.

This Article Contains:

Harlow’s experiments: a brief summary, three fascinating findings & their implications, its connection to love and attachment theory, follow-up and related experiments, criticisms of harlow’s experiments, ethical considerations of harlow’s experiments, relevant positivepsychology.com resources, a take-home message.

Harry Harlow was trained as a psychologist, and in 1930 he was employed at the University of Wisconsin–Madison. His areas of expertise were in infant–caregiver relationships, infant dependency and infant needs, and social deprivation and isolation. He is also well known for his research using rhesus monkeys.

Maternal surrogates: Food versus comfort

For his experiments, Harlow (1958) separated infant rhesus monkeys from their mothers. He then constructed two surrogate ‘mothers’ for the infants: one surrogate made out of metal but that provided milk through an artificial nipple, the other surrogate covered in soft, fluffy material but that didn’t offer food.

The first surrogate delivered food but provided no comfort; the second did not deliver food, but the rhesus infants were able to cuddle with it.

When both surrogates were placed in the infants’ cages, Harlow found the surrogates satisfied different needs of the rhesus infants. The wire surrogate satisfied the infants’ primary need for food. However, when Harlow made a loud noise to frighten the rhesus infants, they ran to the second, fluffy surrogate for comfort.

Maternal surrogates: A secure base from which to explore

In subsequent experiments, Harlow (1958) showed that the fluffy surrogate acted as a secure base from which rhesus infants could explore an unfamiliar environment or objects. In these experiments, the infants, along with their fluffy surrogates, were placed in an unfamiliar environment like a new cage.

These infants would explore the environment and return to the surrogate for comfort if startled. In contrast, when the infants were placed in the new environment without a surrogate, they would not explore but rather lie on the floor, paralyzed, rocking back and forth, sucking their thumbs.

The absence of a maternal surrogate

Harlow also studied the development of rhesus monkeys that were not exposed to a fluffy surrogate or had no surrogate at all. The outcome for these infants was extremely negative. Rhesus infants raised with a milk-supplying metal surrogate had softer feces than infants raised with a milk-supplying fluffy surrogate.

Harlow posited that the infants with the metal surrogates suffered from psychological disturbances, which manifested in digestive problems.

Rhesus infants raised with no surrogates showed the same fearful behavior when placed in an unfamiliar environment as described above, except that their behavior persisted even when a surrogate was placed in the environment with them. They also demonstrated less exploratory behavior and less curiosity than infants raised with surrogates from a younger age.

When these infants were approximately a year old, they were introduced to a surrogate. In response, they behaved fearfully and violently. They would rock continuously, scream, and attempt to escape their cages. Fortunately, these behaviors dissipated after a few days. The infants approached, explored, and clung to the surrogate, but never to the same extent as infants raised with a fluffy surrogate from a younger age.

Primary drives are ones that ensure a creature’s survival, such as the need for food or water. Harlow suggests that there is another drive, ‘contact comfort,’ which the fluffy surrogate satisfied.

The ‘contact comfort’ drive does more than just satisfy a need for love and comfort. From Harlow’s experiments, it seems that these fluffy surrogates offered a secure, comforting base from which infants felt confident enough to explore unfamiliar environments and objects, and to cope with scary sounds.

Conclusions from Harlow’s work were limited to the role of maternal surrogates because the surrogates also provided milk – a function that only female mammals can perform. Consequently, it was posited that human infants have a strong need to form an attachment to a maternal caregiver (Bowlby, 1951). However, subsequent research has shown that human infants do not only form an attachment with:

• a female caregiver,
• a caregiver that produces milk, or
• one caregiver (Schaffer & Emerson, 1964).

The bond between human infant and caregiver is not limited to only mothers, but can extend to anyone who spends time with the infant. Schaffer and Emerson (1964) studied the emotional responses of 60 infants to better understand their attachments and behaviors.

They found that at the start of the study, most of the infants had formed an attachment with a single person, normally the mother (71%), and that just over a third of the infants had formed attachments to multiple people, sometimes over five.

However, when the infants were 18 months, only 13% had an attachment to a single person, and most of the infants had two or more attachments. The other people with whom infants formed an attachment included:

• Grandparents
• Siblings and family members
• People who were not part of their family, including neighbors or other children

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Harlow’s experiment on rhesus monkeys shed light on the importance of the relationship between caregiver and infant. This relationship satisfies other needs besides food and thirst, and the behavior of rhesus infants differs depending on whether they were raised (1) with or without a surrogate and (2) whether that surrogate was a fluffy (i.e., comforting) or metal (i.e., non-comforting) one.

Widespread thinking at the time was that children only needed their physical needs to be satisfied in order to grow up into healthy, well-adjusted adults (Bowlby, 1951, 1958). Harlow’s work, however, suggests that the caregiver satisfies another need of the infant: the need for love.

It is difficult to know whether the infant monkeys truly loved the surrogate mothers because Harlow could not ask them directly or measure the feeling of love using equipment.

But there is no doubt that the presence (or absence) of a surrogate mother deeply affected the behavior of the infant monkeys, and monkeys with surrogate mothers displayed more normal behavior than those without.

Additionally, Harlow’s work also showed that infant monkeys looked for comfort in the fluffy surrogate mother, even if that surrogate mother never provided food.

From this research, we can conclude that infants feel an attachment toward their caregiver. That attachment is experienced as what we know to be ‘love.’ This attachment seems to be important for a variety of reasons, such as:

• Feeling safe when afraid or in an unfamiliar environment
• Responding in a loving, comforting way to the needs and feelings of infants

The infant’s need to form an attachment was not considered a primary need until 1952, when Bowlby argued that this basic need was one that infants feel instinctually (Bowlby & World Health Organization, 1952).

Bowlby’s work formed the basis of attachment theory – the theory that the relationship between infant and caregiver affects the infant’s psychological development.

The contributions from these researchers include:

• The emotional needs of infants are critical to healthy development and survival
• Parents play an important role besides merely satisfying the physical needs of an infant to ensure survival

Maternal deprivation

John Bowlby (1958) argued that maternal deprivation has extremely negative effects on the psychological and emotional development of children.

He was especially interested in extreme forms of parental deprivation, such as children who were homeless, abandoned, or institutionalized and therefore had no contact with their parents.

From his research, Bowlby argued that satisfying the physiological needs of the child did not ensure healthy development and that the effects of maternal deprivation were grave and difficult to reverse.

Specifically, he argued that how the caregiver behaves in response to the behavior and feelings of an infant plays an important role in infants’ psychological and emotional development (Bowlby, 1958).

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Attachment styles in infants

How the caregiver responds to the infant is known as sensitive responsiveness (Ainsworth et al., 1978). The fluffy surrogate mothers in Harlow’s experiment were not responsive, obviously; however, their presence, the material used to cover them, and their shape allowed the rhesus infants to cling to them, providing comfort, albeit a basic, unresponsive one.

The findings from research by Harlow and Bowlby led to pioneering work by Mary Ainsworth on infant–mother attachments and attachment theory in infants. Specifically, she developed an alternative method to study child–parent attachments, using the ‘strange situation procedure’:

• The parent and child are placed together in an unfamiliar room.
• At some point, a (female) stranger enters the room, chats to the parent and plays with/chats to the infant.
• The parent leaves the room, and the child and stranger are alone together.
• The parent returns to the room, and the stranger leaves. The parent chats and plays with the child.
• The parent leaves the room, and the child is alone.
• The stranger returns and tries to chat and play with the child.

Depending on how the child behaved at the separation and introduction of the parent and the stranger, respectively, the attachment style between the infant and mother was classified as either secure, anxious-avoidant, or anxious-resistant.

For more reading on Mary Ainsworth, Harlow, and Bowlby, you can find out more about their work in our What is Attachment Theory? article.

Harlow’s studies on dependency in monkeys – Michael Baker

Subsequent research has questioned some of Harlow’s original findings and theories (Rutter, 1979). Some of these criticisms include:

• Harlow’s emphasis on the importance of a single, maternal figure in the child–parent relationship. As mentioned earlier, children can develop important relationships with different caregivers who do not need to be female/maternal figures (Schaffer & Emerson, 1964).
• The difference between a bond and an attachment. Children can form attachments without forming bonds. For example, a child might follow a teacher (i.e., an example of attachment behavior) and yet not have any deep bonds or relationships with other children. This suggests that these two types of relationships might be slightly different or governed by different processes.
• Other factors can also influence the relationship between child and parent, and their attachment. One such factor is the temperament of the parent or the child (Sroufe, 1985). For example, an anxious parent or child might show behavior that suggests an insecure attachment style.  Another factor is that behaviors that suggest attachment do not necessarily mean that the parent is better responding to the child’s needs. For example, children are more likely to follow a parent when in an unfamiliar environment. This behavior does not automatically imply that the child’s behavior is a result of the way the parent has responded in the past; instead, this is just how children behave.

One of Harlow’s most controversial claims was that peers were an adequate substitute for maternal figures. Specifically, he argued that monkeys that were raised with other similarly aged monkeys behaved the same as monkeys that were raised with their parents. In other words, the relationship with a parent is not unique, and peers can meet these ‘parental’ needs.

However, subsequent research showed that rhesus monkeys raised with peers were shyer, explored less, and occupied lower roles in monkey hierarchies (Suomi, 2008; Bastian, Sponberg, Suomi, & Higley, 2002).

Importantly, Harlow’s experiments are not evidence that there should be no separation between parent and infant. Such a scenario would be almost impossible in a normal environment today. Frequent separations between parent and infant are normal; however, it is critical that the infant can re-establish contact with the parent.

If contact is successfully re-established, then the bond between parent and child is reinforced.

Impact on psychological theories about human behavior

Harlow’s research on rhesus monkeys demonstrated the important role that parents have in our development and that humans have other salient needs that must be met to achieve happiness.

Harlow’s work added weight to the arguments put forward by Sigmund Freud (2003) that our relationship with our parents can affect our psychological development and behavior later in our lives.

Harlow’s work also influenced research on human needs. For example, Maslow (1943) argued that humans have a hierarchy of needs that must be met in order to experience life satisfaction  and happiness.

The first tier comprises physiological needs, such as hunger and thirst, followed by the second tier of needs such as having a secure place to live. The third tier describes feelings of love and belonging, such as having emotional bonds with other people. Maslow argued that self-actualization could only be reached when all of our needs were met.

Harlow continued to perform experiments on rhesus monkeys, including studying the effects of partial to complete social deprivation. It is highly unlikely that Harlow’s experiments would pass the rigorous requirements of any ethics committee today. The separation of an infant from their parent, especially intending to study the effect of this separation, would be considered cruel.

Kobak (2012) outlines the experiments performed by Harlow, and it is immediately obvious that many of these animals experienced severe emotional distress because of their living conditions.

In the partial isolation experiments, Harlow isolated a group of 56 monkeys from other monkeys; although they could hear and see the other monkeys, they were prevented from interacting with or touching them. These monkeys developed aggressive and severely disturbed behavior, such as staring into space, repetitive behaviors, and self-harm through chewing and tearing at their flesh.

Furthermore, the monkeys that were raised in isolation did not display normal mating behavior and failed in mating.

The complete social deprivation experiments were especially cruel. In these experiments, they raised the monkeys in a box, alone, with no sensory contact with other monkeys. They never saw, heard, or came into contact with any other monkeys.

The only contact that they had was with a human experimenter, but this was through a one-way screen and remote control; there was no visual input of another living creature.

Harlow described this experience as the ‘pit of despair.’ Monkeys raised in this condition for two years showed severely disturbed behavior, unable to interact with other monkeys, and efforts to reverse the effect of two years in isolation were unsuccessful.

Harlow considered this experiment as an analogy of what happens to children completely deprived of any social contact for the first few years of their lives.

The effects of Harlow’s experiments were not limited to only one generation of monkeys. In one of his studies, a set of rhesus monkeys raised with surrogates, rather than their own mothers, gave birth to their own infants.

Harlow observed that these parent-monkeys, which he termed ‘motherless monkeys,’ were dysfunctional parents. They either ignored their offspring or were extremely aggressive toward them. They raised two generations of monkeys to test the effect of parental deprivation.

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Harlow’s monkey experiments were cruel, but it would have been impossible to conduct the same experiments using human infants.

Furthermore, Harlow’s experiments helped shift attention to the important role that caregivers provide for children.

When Harlow was publishing his research, the medical fraternity believed that meeting the physical needs of children was enough to ensure a healthy child. In other words, if the child is fed, has water, and is kept warm and clean, then the child will develop into a healthy adult.

Harlow’s experiments showed that this advice was not true and that the emotional needs of infants are critical to healthy development.

With love, affection, and comfort, infants can develop into healthy adults.

We hope you enjoyed reading this article. Don’t forget to download our three Positive Relationships Exercises for free .

• Ainsworth, M. D. S., Blehar, M. C., Waters, E., & Wall, S. (1978). Patterns of attachment: A psychological study of the strange situation . Erlbaum.
• Bastian, M. L., Sponberg, A. C., Suomi, S. J., & Higley, J. D. (2002). Long-term effects of infant rearing condition on the acquisition of dominance rank in juvenile and adult rhesus macaques (Macaca mulatta). Developmental Psychobiology , 42 , 44–51.
• Bowlby, J. (1951). Maternal care and mental health . Columbia University Press.
• Bowlby, J. (1958). The nature of the child’s tie to his mother. International Journal of Psycho-Analysis , 39 , 350–373.
• Bowlby, J., & World Health Organization. (1952). Maternal care and mental health: A report prepared on behalf of the World Health Organization as a contribution to the United Nations programme for the welfare of homeless children . World Health Organization.
• Colman, M. A. (2001). Oxford dictionary of psychology . Oxford University Press.
• Freud, S. (2003). An outline of psychoanalysis . Penguin UK.
• Harlow, H. F. (1958). The nature of love. American Psychologist , 13 (12), 673.
• Kobak, R. (2012). Attachment and early social deprivation: Revisiting Harlow’s monkey studies. Developmental psychology: Revisiting the classic studies , S , 10–23.
• Maslow, A. H. (1943). A theory of human motivation. Psychological Review , 50 (4), 370–96.
• Rutter, M. (1979). Maternal deprivation, 1972–1978: New findings, new concepts, new approaches. Child Development , 50 (2), 283–305.
• Schaffer, H. R., & Emerson, P. E. (1964). The development of social attachments in infancy. Monographs of the Society for Research in Child Development , 29 (3), 1–77.
• Sroufe, L. A. (1985). Attachment classification from the perspective of infant-caregiver relationships and infant temperament. Child Development , 56 (1), 1–14.
• Suomi, S. J. (2008). Attachment in rhesus monkeys. In J. Cassidy & P. Shaver (Eds.), Handbook of attachment: Theory, research and clinical applications (pp. 173–191). Guilford Press.

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Parental attunement and attention also shape the architecture of the brain and the function of the nervous system. When a child does not encounter sufficient parental attunement, compassion, kindness, and empathy, they are deprived of experiences that foster the integration of the brain. This results in a dysregulated nervous system, which cannot produce regulated emotions, thoughts, behaviors, relationships, or bodily systems. The impeded integration causes internal distress, the symptoms of which include chronic illness, recurrent pain, poor relationships, and “mental health” conditions (which are health conditions).

The child (and subsequently insufficiently supported adult) tries to find relief through whatever means are available: numbing, acting out, withdrawing, overeating, substance abuse, dissociation, splitting, self-harm, etc. These are not “disorders” but *survival adaptations* demanded by the unsafe environment. The child/adult uses whatever survival adaptations are available; when they have better options, they use them.

When the dysregulated person receives sufficient psychosocial support, such as through truly therapeutic or other integrative relationships, the brain can integrate and the nervous system can regulate. People, like animals and plants, flourish in supportive environments. Fix the environment and the symptoms fade.

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Psychological Torture Experiments at NIH Must Stop

UPDATE: Following an intensive year-long PETA campaign, the National Institutes of Health announced that it is ending the cruel maternal deprivation experiments on baby monkeys and the Poolesville, Maryland, laboratory is being shut down. Read more .

Where It All Began …

Harry Harlow’s psychological experiments on monkeys in the 1950s, ’60s, and ’70s were infamous for their cruelty. Harlow tore newborns away from their mothers, gave some infants  “surrogate mothers” made of wire and wood, and kept other traumatized babies in isolation in tiny metal boxes, sometimes for up to a year. Realizing that such horrific conditions resulted in long-term, debilitating psychological trauma for the infants, Harlow began expanding his project. He and his then-student Stephen Suomi created the “ pit of despair ,” a dark metal box designed to isolate the monkeys from everything in the outside world. Within days, the monkeys kept inside the pit were driven insane, incessantly rocking and clutching at themselves, tearing and biting their own skin and ripping out their hair. When finally removed from isolation, they were too traumatized to interact with other monkeys, and some were so shocked and depressed that they starved themselves to death. To see what would happen when tormented monkeys became mothers themselves, Suomi and Harlow created what they called a “rape rack” in order to restrain and impregnate female monkeys, then they would later watch and photograph the mentally ill mothers physically abusing and killing their own babies.

Harlow died in 1981 and, though most people believe his experiments are a thing of the past, PETA has learned that his protégé, Stephen Suomi, has continued to conduct similar maternal deprivation and depression experiments on infant monkeys for more than 30 years in taxpayer-funded laboratories at a National Institutes of Health (NIH) facility in Poolesville, Maryland.

A Cycle of Suffering

PETA has obtained documents, hundreds of photographs, and more than 500 hours of never-before-seen high-definition videos taken inside this NIH facility, detailing the ongoing psychological abuse of baby monkeys in disgustingly cruel and archaic experiments that have been funded by more than $30 million just in the past seven years .

Each year, 40 to 60 monkeys are born at this NIH facility, many intentionally bred to be genetically predisposed to mental illness. Half of the monkeys born each year are separated from their mothers within hours of birth and never returned. Some infants are given a cloth-covered water bottle as a “surrogate” mother. As in Harlow and Suomi’s earlier experiments, these motherless infants are more likely to suffer from severe anxiety, aggression, depression, diarrhea, hair loss, and other physical and mental illnesses, as well as engaging in self-destructive behavior such as biting themselves and pulling out their own hair.

The monkeys undergo years of terrifying and often painful experiments to exacerbate their symptoms of mental illness and test the severity of their psychological trauma. Currently, approximately 200 young monkeys are involved in the experiments.

The Video That NIH Doesn't Want You to See

Videos obtained by PETA—that NIH unsuccessfully tried to charge PETA $100,000 for— show how NIH experimenters terrorize the baby monkeys they have intentionally made mentally ill in recent and ongoing experiments.

• Confused, distraught newborns are taken from their mothers and held down by experimenters, and their heads are forced from side to side to see which position they prefer.
• Infants are caged with their mothers, who are chemically sedated, have their nipples taped over, and are placed in a car seat. The terrified babies scream and cry, climbing onto and frantically shaking their unresponsive mothers. In at least one case, experimenters can be heard laughing while a mother tries to remain awake to comfort her distraught child. In some trials, the experimenters even release an electronic snake into the cage with the baby monkeys, who innately fear the reptiles.
• Newborn infants are restrained inside tiny mesh cages and placed in “startle chambers.” The experimenters then deliberately scare the babies with loud noises, causing them to cry out and try futilely to hide or escape.

The videos and photographs depict only a portion of the torment that these animals endure.

As the babies grow older, they are shuttled between NIH laboratories and subjected to years of additional experiments. Some of the distressed monkeys have devices screwed into their skulls so experimenters can inject their brains with a variety of drugs already being safely used to treat human children and adults suffering from mental illness, including Prozac. Other young monkeys are injected with large doses of ethanol—deliberately turning them into alcoholics which increases their anxiety, aggression, depression, and social withdrawal. Others are sold to Wake Forest University, where they are subjected to similar alcohol addiction experiments.

Many of the monkeys are killed and dissected before their 8th birthday.

Bad Science

These experiments continue to be funded and conducted even though they are largely irrelevant to human mental illness and the experimenters themselves have admitted that the work is not applicable to our treatment of human psychological trauma and brain disorders.

Suomi has long acknowledged the irrelevance of his torturous experiments. In 1977, he wrote the following:

[W]hether actual data obtained from nonhuman primates have added measurably to our understanding of human development is another matter. … [S]uch cases are relatively rare. Most monkey data that readily generalize to humans have not uncovered new facts about human behavior; rather, they have only verified principles that have already been formulated from previous human data.

After four more decades of these experiments, nothing has changed. In a recent paper, Suomi and his colleagues drew this conclusion:

[M]any findings from behavioral and biochemical studies in monkeys and other animals are not replicated in humans. Accordingly, this study cannot directly address the safety and efficacy of [anti-depressant drugs] in children and adolescents with psychiatric disorders. … [T]his animal model of maternal separation has never been validated as a measure of drug efficacy in humans. … The only way to know definitively whether [anti-depressant drugs work] in humans would be to study our species.

Meanwhile, researchers throughout the country are suffering from a shortage of funds as they conduct human-based research that can demonstrably benefit human health and well-being. Epidemiological studies, modern brain-scanning techniques, and genetic studies with human volunteers have already established, and continue to uncover, the connections between genes, early life stress, and the development of mental illness in humans.

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Inside twisted experiment where baby named Donald became ‘more ape than human’ before killing himself

• Adrian Zorzut
• Published : 8:30 ET, Oct 6 2021
• Updated : 11:08 ET, Oct 6 2021
• Published : Invalid Date,

A HUMAN baby raised alongside a chimpanzee "became more ape than human" before tragically killing himself later in life.

Animal psychologists Winthrop Niles Kellogg and his wife Luella carried out a bizarre experiment in the 1930s as they raised a chimp named Gua and their son Donald as "brother and sister".

However, the couple got more than they bargained for when it was actually their son Donald who ended up becoming more ape than man.

The experiment had to be cancelled as reportedly the tot started to make noises like a chimp and began to become more aggressive, even biting people.

He grunted and barked like his "sister" when he wanted more food and would mimic her behaviours.

Donald also began to move on all fours like the chimp - and the two would even wrestle like two wild animals.

Seeing what was happening to their son, the Kelloggs terminated the experiment - and Gua was sent away, dying of pneumonia just a year later aged 3.

And while not much more is known about Donald, he later killed himself aged just 43 in 1973.

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On June 26, 1931, the Kelloggs welcomed their new arrival, a baby chimpanzee called Gua, who they would raise alongside Donald.

It was a bid to see whether environment would influence a chimp's development - and how how human they could make it.

The test was due to last five years - but it was abandoned after just nine months.

Other theories as to why the test was axed include claims it was cancelled because Gua was becoming too strong and may have harmed Donald.

Gua was seven-and-a-half months old and Donald was a smidgen older at 10 months when the trial began.

And both infants were subjected to cruel tests such as being hit on the head with spoons, spun round in chairs, and being teased by their mum & dad.

Kellogg was fascinated by children raised in the wild with little to no human help - and felt the best way to try and replicate that was bring a chimp into his home.

"What would be the nature of the resulting individual who had matured … without clothing, without human language and without association with others of its kind?" he asked in his 1933 book, The Ape and the Child.

He knew abandoning a human child in the wilderness was be morally reprehensible so instead, he opted to bring an infant animal into modern society.

For the next nine months, 12 hours a day, seven days a week, Kellogg and his devoted wife - both comparative psychologists - conducted test after test on Donald and Gua.

They were raised in the exact same way: they both wore baby onesies, made to sit in a high chair, slept in a bed and were kissed good night, though Gua was carted around in a small wagon.

Our final concern is why the project ended when it did The Psychological Record

Gua was taught the kind of things a fond parent would do to a baby girl.

All the while, Kellogg ran a barrage of tests and started probing Gua and Donald's "blood pressure, memory, body size, scribbling, reflexes, depth perception, vocalization, locomotion, reactions to tickling, strength, manual dexterity, problem solving, fears, equilibrium, play behavior, climbing, obedience, grasping, language comprehension, attention span, and others," The Psychological Record author's note.

According to one report , the Kelloggs would tap Donald and Gua's heads with spoons to hear the difference in the sound of their skulls and made loud noises to see who would react faster.

They even tried to convince Gua not to eat soap bubbles by jamming a bar of the product into her mouth.

Eerie footage of the experiment shows Gua and Donald being put in high chairs and being spun round and round until they start crying.

They were also pushed to complete cruel tests in which they were put through a labyrinth and forced to get out while the perimeters changed around them.

For a while, Gua excelled in these drills compared to Donald; but after they both turned one, things began to change.

Gua's physical advantages were slowly eclipsed by Donald's ability to formulate words and the doctors soon realised they had hit the chimp's limit of intelligence.

Authors in The Psychological Record said the Kelloggs' experiment "probably succeeded better than any study before its time in demonstrating the limitations heredity placed on an organism regardless of environmental opportunities as well as the developmental gains that could be made in enriched environments".

But the experiment suddenly came to an unexplained end, the publication said, adding: "Our final concern is why the project ended when it did.

"We are told only that the study was terminated on March 28, 1932, when Gua was returned to the Orange Park primate colony through a gradual rehabilitating process.

"But as for why, the Kelloggs, who are so specific on so many other points, leave the reader wondering."

There were rumours they were simply exhausted from nine months of non-stop parenting and scientific work.

Gua showed no signs of learning human languages, but Donald, on the other hand, had began imitating her chimp noises.

"In short, the language retardation in Donald may have brought an end to the study," the The Psychological Record authors wrote.

What's more, OZY reports, Luella Kellogg became increasingly concerned Donald was becoming more chimp than human.

Gua and Donald would wrestle in a way that looked more chimp-like and she had taught her older brother how to spy on people beneath doors.

Donald began biting people and crawled like his sister. He grunted and barked like her when he wanted more food.

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Winthrop continued working at Florida State University where he took up research on bottle-nose dolphins and sonar until his retirement in 1963.

He and wife Luella both died in the summer of 1972.

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Harlow’s Monkey Experiment – The Bond between Babies and Mothers

Harry Harlow was an American psychologist whose studies were focused on the effects of maternal separation, dependency, and social isolation on both mental and social development.

Objective of the Harlow’s Monkey Experiment

The idea came to Harlow when he was developing the Wisconsin General Testing Apparatus or the WGTA to study the mental processes of primates, which include memory, cognition and learning. As he developed his tests, he realized that the monkeys he worked with were slowly learning how to develop strategies around his tests.

Harlow had the idea that infant monkeys who are separated from their mothers at a very early age (within 90 days) can easily cope with a surrogate, because the bond with the biological mother has not yet been established. Furthermore, he also wanted to learn whether the bond is established because of pure nourishment of needs (milk), or if it involves other factors.

How did the Harlow’s Monkey Experiment work?

Results of the harlow monkey experiment.

Furthermore, the results of the second experiment showed that while the baby monkeys in both groups consumed the same amount of milk from their “mother”, the babies who grew up with the terry cloth mother exhibited emotional attachment and what is considered as normal behaviour when presented with stressful variables. Whenever they felt threatened, they would stay close to the terry cloth mother and cuddle with it until they were calm.

Significance of the Harlow’s Monkey Experiment

Moreover, it was found that the establishment of bond between baby and mother is not purely dependent on the satisfaction of one’s physiological needs (warmth, safety, food) , but also emotional (acceptance, love, affection).

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What scientists learned when they tried to raise a chimp with a human baby

By Popular Science Team

Posted on Sep 21, 2021 7:00 AM EDT

What’s the weirdest thing you learned this week? Well, whatever it is, we promise you’ll have an even weirder answer if you listen to PopSci ’s hit podcast . The Weirdest Thing I Learned This Week hits Apple , Anchor , and everywhere else you listen to podcasts every-other Wednesday morning. It’s your new favorite source for the strangest science-adjacent facts, figures, and Wikipedia spirals the editors of Popular Science can muster. If you like the stories in this post, we guarantee you’ll love the show.

FACT: Trading blood could actually make you “young” again

By Corinne Iozzio

Scientists have long thought that blood has the power to reshape us—to make an old person feel young, an ill person well again, and an agitated person find calm. Some of the earliest experiments to test this notion, though, did not have stellar results. When Robert Lower developed a crude transfusion technique that he tested on dogs, the donating puppers didn’t survive. But he and other physicians in the mid-1600s felt they were onto something; more specifically, they wanted to know if “calm” blood could help quiet mental illness. To avoid a dead donor they instead transfused their patients with lamb’s blood. In 1667, a pair of public experiments—one in London and one in Paris—were relatively successful, according to the scientists’ own accounts, at least. But the first Parisian infusion, scientific historian  Holly Tucker recounts in her book  Blood Work , raised some, uh, red flags; the subject had what we now know was a normal immune response to such an incursion. The patient’s eventual death, though suspicious, spurred the government and eventually the pope to put the kibosh on the whole bloody business.

Here’s the thing, though: As Kat McGowan reports in the new issue of  PopSci , these experiments were, in fact, onto something. Over the last couple decades, a  growing body of research  has found that a sustained commingling of blood supplies—so-called parabiosis—can reverse the signs of aging in lab mice. What remains is to figure out precisely what in the blood is spurring those changes and put that into a manageable form like a shot or a pill—no blood trading, necessary.

FACT: Candyland wouldn’t exist without polio

By Rachel Feltman

Polio is one of those diseases that most of us are lucky enough to not have to worry about. Jonas Salk created an extremely effective vaccine for it that was released in 1955, and cases dropped by 85 to 90 percent within just two years of that initial rollout . We haven’t had a case of polio with US origins since 1979, and the last time the virus was brought into the country to spread here was 1993. That’s not because polio has disappeared; it’s because our vaccination rates are so high.

Because of that, it’s easy for us to forget that in the 1950s, polio was a devastating and terrifying disease in the US. In around 1 percent of infections, polio attacks the central nervous system and can lead to permanent paralysis of different parts of the body. Young children are at especially high risk of contracting the virus. 

The height of the US polio epidemic was in the 1950s, just before Salk’s vaccine came out, and there was no cure and no understanding of how to prevent it. Something like 15,000 people were being paralyzed each year in the US alone. With no sense of what would actually help their kids avoid polio, a lot of parents spent the early 50s making kids stay indoors all summer, when transmission rates would peak. It was a really scary time—and a boring one. Enter Eleanor Abbott, a school teacher from San Diego. We don’t know much about her, but we know she contracted polio herself in 1948. And sometime during or after her recovery, she designed Candyland . It’s colorful, it’s simple, and the game mechanic is literally about taking a stroll—which is pretty poignant when you realize she designed it primarily for bedridden kids recovering from illness. Listen to this week’s episode to learn more about Abbott’s story—and other surprising origins of beloved American board games.

FACT: You can’t raise a baby chimpanzee like a tiny human

By Purbita Saha

Brave psychology couple Winthrop and Luella Kellogg gave this experiment a go in the 1930s—and though it led to some fascinating results, it didn’t pan out too well overall. Winthrop, who ran an animal-stimuli lab at Indiana State University and then Florida State University, was intrigued by the case of two “wolf children” in India whose feral instincts stuck with them for life. He wanted to dig into the question: How much can an infant’s environment change its behavior and development?

Winthrop couldn’t quite test his hypothesis on a young human, so he and his wife took in a 7-month-old captive chimpanzee from Cuba to raise alongside their 10-month-old son, Donald. Gua, as the ape was called, received the same care and attention as her “sibling” and was tested daily for a long list of metrics. While she never learned to speak or babble like a person , her physical growth and motor skills progressed quickly—on par with other chimps in captivity. Donald, on the other hand, began imitating Gua’s barks and onomatopoeia, which may have been one reason the experiment ended in just six months.

The Kellogg’s documented their whole endeavor in their book, The Ape and the Child . There’s also a silent documentary that’s mostly available online.

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The ‘forbidden experiment’ is an infamously evil chapter in scientific history the ‘forbidden experiment’ is an infamously evil chapter in scientific history, ants perform teeny tiny operations to save their injured comrades ants perform teeny tiny operations to save their injured comrades.

Harry Harlow with the mother surrogates he used to raise infant monkeys. The terry cloth mother is pictured above. The bare wire mother appears below. Given a choice, infant monkeys invariably preferred surrogate mothers covered with soft terry cloth, and they spent a great deal of time cuddling with them (above), just as they would have with their real mothers (below).   The famous experiments that psychologist Harry Harlow conducted in the 1950s on maternal deprivation in rhesus monkeys were landmarks not only in primatology, but in the evolving science of attachment and loss. Harlow himself repeatedly compared his experimental subjects to children and press reports universally treated his findings as major statements about love and development in human beings. These monkey love experiments had powerful implications for any and all separations of mothers and infants, including adoption, as well as childrearing in general. In his University of Wisconsin laboratory, Harlow probed the nature of love, aiming to illuminate its first causes and mechanisms in the relationships formed between infants and mothers. First, he showed that mother love was emotional rather than physiological, substantiating the adoption-friendly theory that continuity of care—“nurture”—was a far more determining factor in healthy psychological development than “nature.” Second, he showed that capacity for attachment was closely associated with critical periods in early life, after which it was difficult or impossible to compensate for the loss of initial emotional security. The critical period thesis confirmed the wisdom of placing infants with adoptive parents as shortly after birth as possible. Harlow’s work provided experimental evidence for prioritizing psychological over biological parenthood while underlining the developmental risks of adopting children beyond infancy. It normalized and pathologized adoption at the same time. How did Harlow go about constructing his science of love? He separated infant monkeys from their mothers a few hours after birth, then arranged for the young animals to be “raised” by two kinds of surrogate monkey mother machines, both equipped to dispense milk. One mother was made out of bare wire mesh. The other was a wire mother covered with soft terry cloth. Harlow’s first observation was that monkeys who had a choice of mothers spent far more time clinging to the terry cloth surrogates, even when their physical nourishment came from bottles mounted on the bare wire mothers. This suggested that infant love was no simple response to the satisfaction of physiological needs. Attachment was not primarily about hunger or thirst. It could not be reduced to nursing. Then Harlow modified his experiment and made a second important observation. When he separated the infants into two groups and gave them no choice between the two types of mothers, all the monkeys drank equal amounts and grew physically at the same rate. But the similarities ended there. Monkeys who had soft, tactile contact with their terry cloth mothers behaved quite differently than monkeys whose mothers were made out of cold, hard wire. Harlow hypothesized that members of the first group benefitted from a psychological resource—emotional attachment—unavailable to members of the second. By providing reassurance and security to infants, cuddling kept normal development on track. What exactly did Harlow see that convinced him emotional attachment made a decisive developmental difference? When the experimental subjects were frightened by strange, loud objects, such as teddy bears beating drums, monkeys raised by terry cloth surrogates made bodily contact with their mothers, rubbed against them, and eventually calmed down. Harlow theorized that they used their mothers as a “psychological base of operations,” allowing them to remain playful and inquisitive after the initial fright had subsided. In contrast, monkeys raised by wire mesh surrogates did not retreat to their mothers when scared. Instead, they threw themselves on the floor, clutched themselves, rocked back and forth, and screamed in terror. These activities closely resembled the behaviors of autistic and deprived children frequently observed in institutions as well as the pathological behavior of adults confined to mental institutions, Harlow noted. The awesome power of attachment and loss over mental health and illness could hardly have been performed more dramatically. In subsequent experiments, Harlow’s monkeys proved that “better late than never” was not a slogan applicable to attachment. When Harlow placed his subjects in total isolation for the first eights months of life, denying them contact with other infants or with either type of surrogate mother, they were permanently damaged. Harlow and his colleagues repeated these experiments, subjecting infant monkeys to varied periods of motherlessness. They concluded that the impact of early maternal deprivation could be reversed in monkeys only if it had lasted less than 90 days, and estimated that the equivalent for humans was six months. After these critical periods, no amount of exposure to mothers or peers could alter the monkeys’ abnormal behaviors and make up for the emotional damage that had already occurred. emotional bonds were first established was the key to they could be established at all. For experimentalists like Harlow, only developmental theories verified under controlled laboratory conditions deserved to be called scientific. Harlow was no . He criticized psychoanalysis for speculating on the basis of faulty memories, assuming that adult disorders necessarily originated in childhood experiences, and interpreting too literally the significance of breast-feeding. Yet Harlow’s data confirmed the well known psychoanalytic emphasis on the mother-child relationship at the dawn of life, and his research reflected the repudiation of and the triumph of therapeutic approaches already well underway throughout the human sciences and clinical professions by midcentury. Along with child analysts and researchers, including and René Spitz, Harry Harlow’s experiments added scientific legitimacy to two powerful arguments: against institutional child care and in favor of psychological parenthood. Both suggested that the permanence associated with adoption was far superior to other arrangements when it came to safeguarding the future mental and emotional well-being of children in need of parents. of this page by Boris Kozlow] | | | | | | | Site designed by:   Department of History, University of Oregon Eugene, Oregon 97403-1288 (541) 346-3699 E-mail: © Ellen Herman Harlow’s Monkey Experiment (Definition + Contribution to Psychology) Not all experiments in psychology involve humans; nevertheless, those utilizing animals often aim to shed light on human behavior. Harlow's Monkey experiments had a significant impact on psychology, and despite being considered controversial, they remain influential to this day. What Are Harlow’s Monkey Experiments? Harlow's Monkey experiments looked at the influence of parental guidance and interaction during early development. Infant monkeys were placed in isolation, away from their mothers. In other experiments, he took infant monkeys away from their mothers but placed them in a cage with “surrogate” mothers. In both sets of experiments, he found that the monkeys displayed a specific set of behaviors as a response to their unusual upbringing. Psychology Before Harlow's Monkey Experiments Harry Harlow, the man behind the monkey experiments, was a psychologist in the first half of the 20th century. At the time, some conflicting ideas were going around about parenting styles. Early behaviorists didn’t think parents should be so cuddly. Watson told parents that lots of physical affection would slow down their development. For years, psychology students were taught that B.F. Skinner’s daughter was subject to the behaviorist’s experiments, and she went crazy after being isolated in a glass box for the first year of her life. Skinner said that she was raised just fine in isolation. (Skinner’s daughter refutes some rumors in a Guardian article .) As time went on, psychoanalysts like Freud theorized that a child’s development was stunted if the mother didn’t provide love and attention in the first year of the child’s life. If a child experienced trauma during this year, they would develop an oral fixation. After all, getting fed was the most important experience in the first year of a child’s life. There were a lot of different ideas on how to raise a child. And it makes sense that most parents wanted to do the “right” thing. So psychologists started to build experiments to test some of these theories. Harry Harlow was one of them. But rather than studying children, he studied rhesus monkeys. His experiments were very different from a lot of psychologists at the time. He wanted to focus on the impact of love and basic physiological needs. What Happened During Harlow's Monkey Experiments? The monkeys in isolation were separated from other monkeys for 3-12 months. During that time, some would display behaviors to possibly “self-soothe.” Others would self-mutilate. They would circle anxiously and appear to be distressed. Harlow also studied what happened when these monkeys were placed back in the company of other monkeys. The results were slightly disturbing. They continued to self-mutilate. They couldn’t integrate themselves into society. These isolated monkeys were scared, aggressive, or dumbfounded. Some of the monkeys died after they stopped eating. Harlow noted that the longer the monkeys stayed in isolation, the harder it was for them to integrate into society. Monkeys With Wire or Cloth Mothers So the monkeys were negatively affected by isolation. But Harlow wanted to go further. Why were the monkeys impacted so significantly? Was it solely because of physiological factors, or did love and affection play a role? To answer these questions, Harlow set up another experiment. He took the infant monkeys away from their mothers and placed them in a cage with two “surrogate” mothers. One of these surrogate mothers was made out of wire. The other was made out of cloth. In some cages, the wire mother had food for the monkeys. The cloth mother did not. In other cases, the cloth mother had food for the monkeys. The wire mother did not. Harlow observed that no matter which surrogate mother held the food, the infants would spend more time with the comforting cloth mother. If only the wire mother had food, the monkeys would only go to them when hungry. Otherwise, they would stay in the comfort of the cloth mother. This doesn’t mean that the monkeys were fully developed socially. When these monkeys were placed back into cages with other monkeys, they didn’t integrate well. They were shy, didn’t stand up for themselves if bullied, and had trouble mating. The monkeys that did become mothers also had trouble raising their monkeys. Harlow believed these behaviors resulted from the events in their infancy. Attachment Theory and Harlow's Monkey Experiments Suppose you have ever read anything from relationship experts or counselors. In that case, you might hear this idea: our relationship with our parents influences the partners we pick and the way we go about relationships. Many psychologists have shared variations of this idea. Some of these variations are cringe-worthy, and some are quite helpful. One variation of this idea is Attachment Theory . This theory describes four different types of attachments that we develop based on our relationship with our parents. We bring this attachment style (secure, anxious, etc.) into adult relationships. Attachment Theory was the product of studies conducted by John Bowlby and Mary Ainsworth. However, their studies are not the only ones influencing how we view attachment formation. One set of experiments, Harlow’s Monkey experiments, played a role in influencing how we view attachment. Due to the unethical nature of this experiment, it’s not always discussed in a psychology class or discussions about relationships. Controversy and Other Studies on Attachment If you think, “Those poor monkeys!” you’re not alone. Many people believed that Harlow’s experiments were unethical. Why would you subject live animals to an experiment that would ultimately traumatize them? Remember, some of these monkeys died early due to starvation caused by anxious behaviors. Did those monkeys need to die for the good of science? While some say yes, others say no. Not all studies on attachment took such harsh measures. For example, John Bowlby and Mary Ainsworth observed parents and children as parents left the room for a few minutes at a time. You can learn more about these studies, and the Attachment Styles developed as a result of these studies in another video. Despite the controversy surrounding his experiments, Harlow did positively impact the world of psychology and parenting. The risks he took for studying love and care, when those topics weren’t discussed in psychology, paid off. His work showed the importance of love and affection. Caregivers, parents, and guardians took note. If your parents or grandparents showed you love and affection as a child, you can thank the research of Harry Harlow and other psychologists who studied Attachment and development. Related posts: Dreams Of Monkeys Meaning (12 Reasons + Interpretation) Attachment Styles Theory (Free Test) John Bowlby Biography - Contributions To Psychology Mary Ainsworth (Biography) Golden Child Syndrome (Definition + Examples) Reference this article: About The Author Free Personality Test Free Memory Test Free IQ Test PracticalPie.com is a participant in the Amazon Associates Program. As an Amazon Associate we earn from qualifying purchases. Follow Us On: Youtube Facebook Instagram X/Twitter Psychology Resources Developmental Personality Relationships Psychologists Serial Killers Psychology Tests Personality Quiz Memory Test Depression test Type A/B Personality Test © PracticalPsychology. All rights reserved Privacy Policy | Terms of Use June 1, 2015 Cruel Experiments on Infant Monkeys Still Happen All the Time--That Needs to Stop Experiments that separate infant monkeys from their mothers cause profound and unnecessary suffering. They should be stopped Raised in total or partial social isolation, clinging desperately to wire or cloth “mothers,” rhesus monkey infants subjected to American psychologist Harry F. Harlow's maternal-deprivation experiments in the 1950s self-mutilated, rocked, and showed other signs of deep depression and anxiety. Based on the principle that animal models could illuminate issues of maternal care and depression in humans, Harlow's research is still discussed in psychology, anthropology and animal behavior classes. Yet this kind of profound primate suffering is not consigned to the historical record. Today rhesus monkey infants are still forcibly separated by laboratory researchers from their mothers and stressed in ways that leave them physically and emotionally traumatized. At the Eunice Kennedy Shriver National Institute of Child Health and Human Development's Laboratory of Comparative Ethology (LCE) in Poolesville, Md., headed by psychologist Stephen Suomi, infant monkeys are taken from their mothers often within hours of birth. For 22 hours a day (24 on weekends), these infants have no cage mates with which to interact. As I know from my work with free-ranging infant wild baboons in Kenya—monkeys that have a social organization similar to that of the rhesus—this regimen results in a terrible distortion of the animals' natural way of life. In the wild, these monkey infants live at the secure center of a matriline, a group of related females. They play with peers and explore their world but scamper back to the warmth and protection of the most important being in their lives, the mother. At the LCE, in contrast, the motherless infants undergo stressors (such as being intentionally frightened while they are alone) in experiments designed to evaluate their reactivity and thus to understand developmental risk factors leading to mental illness in humans. Peer-reviewed literature from the LCE reports that these infants suffer behavioral and biological consequences for the duration of their lives, including poor health, increased stress, maternal incompetence and abnormal aggression. On supporting science journalism If you're enjoying this article, consider supporting our award-winning journalism by subscribing . By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today. As a person who watches two beloved family members struggle with mental illness, I know the importance of research in this arena. Yet systematic reviews tell us conclusively that animal models do not translate well to human mental health. To treat mental illness in humans requires direct attention to the real stressors we experience in our own lives—not artificial ones that we make rhesus infants endure. Research of diverse types, including neuroimaging and long-term follow-up of patients' day-to-day lives, is making substantive inroads in this endeavor. It is no adequate defense to note that this kind of research meets federal and university animal care guidelines. The bar to gain approval to experiment invasively on primates (and other animals) is quite low. As Lawrence Arthur Hansen pointed out two years ago in the Journal of Medical Ethics , oversight committees are disproportionately composed of the very people who derive their livelihood from continuing these experiments: animal researchers and institutional veterinarians. Bringing onboard knowledgeable parties who do not directly benefit from money awarded to these projects—social scientists and bioethicists, for instance—would be a first step in addressing this skew. As Hansen observes, though, equally necessary is a change in institutional culture to ensure that committees more directly consider benefit-harm issues. I am struck by parallels with the case of biomedical research on chimpanzees at the National Institutes of Health, which in 2011 was deemed “unnecessary” by an independent Institute of Medicine review. Repeatedly, biomedical studies on chimpanzees had been approved by review boards and animal care committees. The oversight process did not ethically protect those lab chimpanzees in the past, and it is not ethically protecting the lab monkeys now. It is not necessary to be against all biomedical research on nonhuman primates to see how outdated and misguided some research is. It is time to end Harlow's cruel legacy. We need your support today Independent journalism is more important than ever. Vox is here to explain this unprecedented election cycle and help you understand the larger stakes. We will break down where the candidates stand on major issues, from economic policy to immigration, foreign policy, criminal justice, and abortion. We’ll answer your biggest questions, and we’ll explain what matters — and why. This timely and essential task, however, is expensive to produce. We rely on readers like you to fund our journalism. Will you support our work and become a Vox Member today? Future Perfect What can caged lab monkeys tell us about free human beings? Where biomedicine gets it wrong about primate research. by Garet Lahvis A friend says they can always tell when you’re hungover. The way you close the cage latch. With so little to do, their attention can focus on those subtle differences in movement: the way it turns, whether it drops all or part of the way. After easing the latch back open, the monkey climbs down to the concrete floor, past the rolling service station with its cotton swabs, boxes, bottles, and syringes. Out in the hallway, two caretakers see him crouched against the cinderblock wall, hands pressed against the cream-colored paint, shoulders pulled up, head turned sideways and facing down the corridor, eyes toward them. Over the past couple of years, experimentation on non-human primates has had a run of bad publicity. In 2020, media attention focused on a federal laboratory that studied the neurobiology of anxiety by scaring monkeys with toy snakes . In November, the US Justice Department indicted members of an alleged “primate smuggling ring” for trafficking and selling wild long-tailed macaques , an endangered species, to biomedical researchers in the US. Around the same time, attention turned to the Livingstone Lab at Harvard University, where researchers sewed baby macaques’ eyelids shut to investigate how visual deprivation affects brain development. The controversy landed in Science magazine , where scientists debated the ethics of blinding monkeys. I was asked to weigh in. But my questions were different — less about the blinded macaques, and more about the controls staring at their cage walls. For 16 years, I worked as a professor for medical schools in Wisconsin and Oregon. Both universities had primate centers. I knew about their operations, though I never experimented on primates. Instead, my laboratories mostly studied mice. Our goal was to identify the genetic and pollutant risk factors for autism, a disability that features challenges with social emotions. We never successfully identified any risk factors, but we did discover that mice enjoy one another’s company and have empathy for their pain. After publishing more than 40 scientific papers, I left academia. In part, I left on principle. I believed that if we experimented on animals, we were obligated not to waste them. I also believed that biomedical scientists were obliged to consider the implications of our own discoveries — like how our animals were responding to their cage environments — so we could do better science. Eventually, I lost faith in the process. I also lost the stomach to confine sentient creatures to tiny cages. Scientists know that the tight confinement of standard laboratory cages distorts the psychology and physiology of our animal subjects. Yet despite a half-century of evidence, we continue to cage them as if their biology is baked into their genetics. From decades of rodent studies, scientists know that an animal’s brain anatomy and physiology are highly vulnerable to even modest changes in their living environments. Mice housed in standard cages, rather than slightly larger ones furnished with blocks and tunnels for mental stimulation, are more susceptible to drug abuse, genetic modifications, and toxic chemicals. Monkeys, nearly our next of kin, can become so mentally deranged by their cage environments that they no longer resemble healthy humans. They might have more in common with children housed in Romanian orphanages in the 1980s and 1990s, who were so deprived of human contact that they still struggle with lifelong physiological and psychological disabilities . Can we use mentally damaged animals to model mental health? Primate experiments have undeniably aided the discovery of treatments for human disease, particularly vaccines and surgical techniques. More than a century ago, for example, scientists collected extracts from the spinal cord of a boy who died of polio, injected them into monkeys, studied how the infection spread, and then developed a vaccine that nearly eradicated polio. Much more recently, primate experiments were useful for developing a brain-spine interface that can restore the ability of people with paralysis to walk . But these successes have been rare. Part of the problem lies in the question we now ask. Globally, scientists use approximately 100,000 non-human primates at any given time, often to explore highly nuanced questions, like finding risk factors and treatments for mental health challenges — autism, ADHD, schizophrenia, addiction, anxiety, depression, post-traumatic stress disorder. And here, we mostly fail. Most drugs showing extreme promise in animal studies fall short in human trials. We haven’t developed a new category of drugs for treating psychiatric illness in more than 50 years; new psychiatric drugs introduced over the same period have been modified versions of existing drugs. Scientists also use primates to understand how human-like immune systems respond to infectious diseases — but, like mental health, immunity is also highly sensitive to how the monkeys feel inside their cages. Housing for monkeys is tight. The standard cage for a rhesus macaque, a common laboratory primate, is about 2.5 feet across, narrow enough for its inhabitant to touch both walls at once. By contrast, their wild relatives can navigate home ranges averaging about 1.5 square miles. Macaques are built to navigate 740 American football fields’ worth of savannah grasslands and forest canopies. Yet inside biomedical labs, they typically get confined to the equivalent of a telephone booth . Housing situations vary. Some live “singly housed” — a situation that resembles solitary confinement, often for a few months, sometimes for life. Others get “protected contact” — two monkeys separated by a grate that permits fingertips to touch. Others live as “buddies in a cage” — sharing the space of a shower stall until one buddy gets pulled out, often leaving the remaining one stressed and with a depressed immune system for weeks to months depending on his temperament (and, perhaps, how close he felt to his buddy). In some respects, singly housed monkeys have it better than human inmates in solitary. For instance, they can more easily hear each other vocalize. Some have handheld mirrors to see their neighbors. Many have opportunities to rattle their squeeze bars, the metal poles fixed to the cage’s back walls, used to pull the monkeys forward for procedures like injections and blood draws. But while the United Nations considers more than 15 days of solitary confinement in humans to be torture, research monkeys often get a lifetime — especially if they lose it and assault their buddy in the cage. And although humans in solitary get time each day outside their cell, primates usually don’t get a break. Studies show that human solitary confinement in prisons can cause depression, anxiety, paranoia, violent fantasies, full-blown panic attacks, hallucinations, psychosis, and schizophrenia. Some incarcerated people also self-mutilate, cutting their wrists and arms, ingesting foreign objects, self-burning, and reopening stitches from prior injuries. Physical symptoms include cardiovascular disease , migraine headaches, back pain, profound fatigue, and deterioration of eyesight. Likewise, lab monkeys express behaviors that suggest psychological trauma. Among 362 singly housed rhesus monkeys, a study found that 89 percent expressed abnormal behavior. Most were what we call “stereotypies” — repetitive behaviors that serve no purpose, save coping. Some monkeys pace in circles. Others rock or bounce for hours, like idling engines. Some methodically somersault. Others incessantly rattle their squeeze bars. A few spend time in “eye salute,” a euphemism for self-stimulation by sticking fingers into one’s own eye. My friend tells me he’s seen some monkeys cross the line of no return. Unresponsive to the caretakers interacting with them, they can’t stop rocking, twirling, circling, or twitching. They can’t pull away from the back of the cage. Their eyes no longer make contact. Up to 15 percent of laboratory monkeys self-mutilate . They might pluck single hairs from their backsides until they turn bright pink, or bang their heads repeatedly against their cage walls, or bite themselves deep enough to require sutures. Unlike their wild brethren, caged macaques often paint the walls with their feces — a substance they can manipulate. Nearly one-quarter of caged macaques express “floating limb” behaviors. Watch one for long enough and you might see his leg writhe or kick. He might grab his leg as it slowly elevates, seemingly out of control. It might hover behind his back. Or his foot might relentlessly smack the back of his head. He might respond by attacking his leg, as if it were foreign. Scientists have normalized the idea that their caged primates are healthy I suspect these behaviors are manifestations of an intolerable allostatic load : a “wear and tear on the body and brain resulting from chronic overactivity or inactivity of physiological systems that are normally involved in adaptation to environmental challenge.” Cramped living spaces deny primates the ability to act on their innate motivations: to seek pleasures, avoid discomforts, and explore complex and changing environments. Oysters don’t need these motivations because they can flourish cemented to a rock. For moving animals, motivations help us make decisions. An innate taste for sugar and salt prompts us to seek the calories and sodium we need to survive. When scientists remove the pleasure center of a rat brain, called the nucleus accumbens, they no longer eat . Curiosity is also an innate drive. In the wild, animals feel compelled to investigate their environments — where to go, what to eat, with whom to interact — to know their options when their situations change. Scientists leverage an animal’s innate curiosity to study how memory works: Introduce a laboratory mouse to a novel object and a familiar one, and if the rodent remembers the object they encountered before, they’ll spend more time sniffing the unfamiliar one. Since the 1950s , scientists have known that monkeys will solve complex puzzles simply for the challenge of solving the task. I suspect that, deprived of varied and ongoing challenges to overcome, environments to explore, or a natural range of body movements, caged monkeys — studied because they resemble us — go insane with boredom. Still, I’ve heard scientists insist that these animals are happier in cages because they get food, water, and safety from predators. They’ll tell you laboratory primates get “environmental enrichment,” like a rubber ball stuffed with a treat, a toy dangling from a cage door, a mirror to play with, or snacks scattered on the cage floor. I suppose they get exercise, too. For glutes and biceps, they can rock back and forth or rattle their cage doors. For a cardio workout, they can pace in circles or slam themselves against the cage walls. Here’s the rub. Scientists must believe that lab animals thrive physically and mentally — not for animal welfare reasons, but to justify our experiments. We need healthy controls, not psychologically broken ones, to benchmark our disease models. And we need the animals used as disease models to be otherwise healthy because we lack the scientific capacity to separate the biology of a nuanced disorder, like autism or ADHD, from confounding factors like the mental damage caused by incarceration. My qualm with the Livingstone Lab’s experiment, the one that entailed sewing baby monkeys’ eyelids shut, is not primarily ethical but scientific. They claimed that by blinding monkeys, they could gain “insight into evolutionary changes in the functional organization of high-level visual cortex.” But they wrongly presumed that their “healthy” control monkeys, who were denied most visual stimulation save the depleted sensory environment of a steel-gray cage, had normal visual functioning. By describing what they’re studying as “evolutionary changes,” the researchers lured us into believing the ridiculous — that brain development behind steel bars is not only normal but natural enough to be relevant to evolutionary changes occurring outside the lab. Yet their monkeys experienced no full spectrum of color, no natural movement like the rustling of leaves, and no passing landscape. Like most other primate experimenters, the lab normalized the idea that monkeys naturally live inside telephone booths, not in the vast, dynamic, and aesthetically complex expanses of nature. What bothers me most is that the scientific community expresses so little concern about whether we’re chasing artifacts of confinement. And for the few of us who ask, the answer is loud with silence. Can we do better? Admittedly, scientists are in a fix. Our problem might have begun during the late Middle Ages, about 800 years ago, when Italian philosopher and theologian Thomas Aquinas argued that because animals lacked “rational souls,” they were like machines. Centuries later, René Descartes, a father of modern science, called animals automata , robots driven by reflexes, without thoughts or feelings — like the mechanical men of his era, built to hammer the bells of village clock towers. Armed with this philosophy, scientists tacked dogs to walls and opened them up without anesthesia to learn that the heart, not the liver, pumped blood. Their shrieks and howls were thought of as if they were bells ringing on the hour. The cruel irony is that the ethical justification for experimenting on animals — that they lack subjective experiences — allowed us to find cogent evidence that they do. Now we’re forced to ignore what we’ve learned from science — so that we can keep doing it. Rather than envision a new paradigm, scientists have devised arguments to keep things the same, claiming, for example, that we need small cages to control for confounding variables in an animal’s environment. But we routinely accept the inescapable variables inside their confines — sound, lighting, food quality, social situations — that are either impossible or too inconvenient to control. In truth, we use small cages because they afford the cheapest and most convenient way to generate scientific publications. What could scientists do differently? We could pivot to more helpful alternatives. We could deploy spatially and temporally complex spaces to study smaller organisms under conditions where they might thrive like the free human beings they are meant to resemble. Mice and rats could live in small research barns with varied food and shelter options and penned-in outdoor access, where they could author their own experiences and meet ongoing and unpredictable challenges . Zebrafish, snails, and fruit flies could also get environments complex enough to operate as they might in the wild. Remote technologies could help deliver various drugs and biomolecules to moving animals and help us monitor their responses. Biomedical research institutions could double down on financially neglected health research programs, like disease prevention. We could expand monitoring of human and wildlife populations for elevated pockets of disease — like cancer, congenital disorders, and mental illness — arising from our exposures to thousands of pesticides and industrial contaminants. Present-day concerns over “forever chemicals” in our food and drinking water , and the enormous price tag we now face for cleanup, could have been predicted and more easily remediated decades ago, when epidemiologists and chemists found evidence of their presence in humans and wildlife. The elevated prevalence of congenital disorders, endocrine disruption, immune dysfunction, and mental illness found in fish-eating wildlife in pollutant hot spots around the Great Lakes and along the US coasts could be used to identify regional exposures to chemical mixtures that also threaten human health. Why not focus on these issues ? With advanced epidemiological computer modeling, and gene sequencing tools, along with high-efficiency cell culture systems that can test multiple chemicals at a time without the use of animals, we could identify harmful compounds, then remove them. The potential is far greater than whatever we might learn from using rubber snakes to scare mentally enfeebled monkeys. Many people believe that science differs from blind faith. If that’s true, I wonder how many more rabbit holes we’ll plumb before we see that cage-deteriorated primates don’t resemble free human beings. Perhaps scientists collectively disregard animal subjectivity out of fear of the moral implications of experimenting on other sentient creatures. Or are we blinded by our ambitions for careers and legacies? No matter the cause, we have obligations to the societal trust placed in us. And if we’re 1,000 years overdue for a paradigm shift, let’s hope that today’s young scientists can find the unfettered clarity of sight to make it happen. The fugitive still cowers in the main hall, cheek and chest pressed against the cinderblock, eyes looking upward, seemingly fixed on the audible ballast of the fluorescent lights. Or the fly circling, then resting, beneath it. He might hear the buzz of both, one against the other, a two-tone that cannot calm the anxiety of being outside that room. Having known only metal walls and the fetid mire of idling bodies, he lacks familiarity with concrete surfaces, unfouled air, and the taking of risks. The protocol is straightforward. Face the escapee, chest out, shoulders straight, eyes toward his. Wedge open the colony room door. Use push brooms to coax him back into his cage. The convict returns. They close his cage door. He pivots, then grabs the bars of the door as if he’s now the master, then shakes them violently like he’s trying to get out. He’ll be studied over and over again because he somehow represents us. Maybe he does. Garet Lahvis was an associate professor and the graduate program director of behavioral neuroscience at Oregon Health and Science University. He is currently writing a book for the University of Chicago Press on his experiences with the limits of science, and of the scientific community, in addressing some of our most pressing biomedical issues. Follow him on X (formerly Twitter) at @GLahvis . Animal Welfare Neuroscience Most Popular There’s a fix for AI-generated essays. Why aren’t we using it? Did Brittany Mahomes’s Donald Trump support put her on the outs with Taylor Swift? Take a mental break with the newest Vox crossword I can’t take care of all my mom’s needs. Am I a monster? America’s love affair with the increasingly weird Kennedys Today, Explained Understand the world with a daily explainer plus the most compelling stories of the day. This is the title for the native ad More in Future Perfect ChatGPT didn’t write this and I can prove it. Is anything really “cruelty-free”? From granola bars to chips, more studies are revealing that UPFs are tied to diseases like cancer and depression. Too much fluoride might lower IQ in kids, a new federal report says. The science (and debate), explained. EVs help reduce greenhouse emissions. But too many used gas-guzzlers could make that impossible. The US military’s recruiting crisis, explained. Skip to main content Keyboard shortcuts for audio player 13.7 Cosmos & Culture Still now, should lab monkeys be deprived of their mothers. Barbara J. King On Monday, the animal advocacy organization PETA released material in support of its campaign to shut down a series of experiments on infant rhesus monkeys carried out at the Laboratory of Comparative Ethology, part of the National Institutes of Health. The material includes excerpts from more than 500 hours of videotape obtained by PETA through the Freedom of Information Act, analysis of scientific papers published by the NIH researchers, and letters from scientists not affiliated with PETA who explained why the experiments are cruel and examples of poor science. The NIH experiments past and future, according to NIH documents obtained by PETA, are attempting to show how environmental influences, like abuse and neglect, act together with genetics to produce individual developmental trajectories. I was one of the scientists to write a letter, and I appear in the short video excerpt prepared by PETA, which you can watch below. (A word of warning: This footage is tough to see, because baby monkeys are intentionally scared and stressed in intense ways.) The rhesus monkeys in this lab are intentionally bred for increased likelihood of psychopathology (via alleles of the 5H-TTT and MAO-1 genes, for those who know genetics), some are separated from their mothers 24 hours after birth, and made to undergo trauma ranging from being frightened by masked humans or strange noises, to being made to observe their mother fade into drugged unresponsiveness. In monkeys such as these rhesus, and the baboons I observed in Amboseli National Park, Kenya, years ago, the mother-infant relationship is the primary one — and it's extremely strong. Under normal circumstances, the babies are clasped to the mother's body continuously for weeks, at which point the little one embarks on a path of greater independence. This means venturing off the mom's body and scampering a few feet, at first, to explore food or other monkeys, then rushing back to mom's safety. I remember so vividly from the Kenyan savanna watching the babies' first brave-then-not-so-brave-after-all steps away from the individual closest to them in the world, and the rushing back to her for a dose of comfort. At NIH, the infants in these experiments, year after year, aren't so lucky. They suffer doubly because they are first taken from their mothers, then left to cope with trauma on their own. It's clear to me, and to the other scientists including famed chimpanzee researcher Jane Goodall who also protested in letter form what NIH is doing, that the baby monkeys suffer emotionally. That suffering is the overwhelming factor for me in assessing these experiments. But there's another point to be made as well. Many people know about Harry Harlow's maternal-deprivation experiments with monkeys from the 1950s. Harlow showed us that baby monkeys collapse into depression and otherwise alter their behavior significantly when taken from their mothers. Yet the NIH lab has sustained the same type of research for the past 30 years, producing results that — in understanding human psychopathology such as anxiety and depression — are of little or no value. Modern techniques of neuroscience, including imaging scans of human brains, make effective alternatives. Even participants in a workshop at the National Institutes of Mental Health who were entirely open to designing future opportunities for animal models for human health, including human mental health, reached this conclusion back in 2001: "The probability of developing comprehensive animal models that accurately reflect the relative influences of factors contributing to anxiety disorder syndromes [in humans] is quite low." PETA's director for laboratory investigations, Justin Goodman, summed up PETA's own perspective for me in an email sent yesterday: "These experiments are unjustifiable from every perspective. They cause baby monkeys crippling emotional trauma, they have never lead to or improved treatments for human mental illness, and they are superseded by modern non-animal research methods that are actually relevant to humans. It's shocking that NIH has allowed these studies to continue for 30 years, but they can't go on any longer." When CBS news covered the PETA campaign on Monday morning, NIH scientists responded to PETA's charges. Lead researcher Stephen Suomi told CBS , in part: "The same behavioral, neurological and health changes seen in nursery-reared monkeys are seen in children who were orphaned from their mothers, or raised by depressed, abusive, or neglectful mothers." We have known that fact for over 50 years now. What was considered novel, relevant and ethical in Harlow's day is none of those things now. Contrary to what NIH told CBS, the Freedom of Information Act files (which I have seen myself) report that the human-intruder experiments, and the selective breeding and maternal-deprivation practices that underlie them, are funded to continue at NIH through 2017. Barbara's most recent book on animals was released in paperback in April. You can keep up with what she is thinking on Twitter: @bjkingape mental health Freedom of Information Act baby monkeys national institutes maternal deprivation rhesus monkeys Watch CBS News Questions raised about mental health studies on baby monkeys at NIH labs By Jessica Firger Updated on: September 8, 2014 / 12:55 PM EDT / CBS News Newly released photos, video and lab reports document years of mental health studies conducted on baby rhesus monkeys at two federally-funded labs in the National Institutes of Health Intramural Research Program. Through a Freedom of Information Act request, People for the Ethical Treatment of Animals (PETA) obtained more than 500 hours of video, hundreds of photographs, as well as animal study proposals and scientific reviews from the NIH, some of which were provided exclusively to CBS News for review. The studies, which began in 2007, attempt to model some of the environmental risk factors associated with human mental illness, such as parental neglect and childhood abuse or trauma, in an effort to understand how they interact with genetic factors. Methodologies used in the studies included separating baby monkeys from their mothers shortly after birth; sedating a mother in the baby's presence to see how it responds when she loses consciousness; intentionally startling monkeys with sudden, loud noises; and subjecting the monkeys to invasive procedures such as spinal taps and intracranial administration of medications. As a result of its investigation, PETA is accusing the researchers of causing the baby monkeys undue harm, amounting to what it calls "child abuse." "The one thing that we have learned from these experiments from the NIH is that monkeys are like us in ways that matter," Justin Goodman, director of PETA's laboratory investigations department, told CBS News. "They need the love and comfort of their mothers when they're young, they need the companionship of the families and peers. When they're deprived of that they are devastated emotionally and physically." In an email to CBS News, one of the lead researchers, Stephen J. Suomi at the National Institute of Child Health and Development (NICHD), disputed the accusation of abuse, insisting that the studies "are conducted with the highest ethical standards at specialized centers that employ professional staff and highly skilled caretakers to ensure humane care of these animals, and are in strict accordance with animal welfare regulations and accreditations." In addition to Suomi's lab, the experiments in question were also conducted at the National Institute of Mental Health under the late Dr. James Winslow; principal investigator Bruno Averbeck took over after Winslow's death and was not involved at the time, the NIH said. Goodman said PETA believes the experiments are not only cruel, they're also unnecessary because similar issues have already been studied in human populations or could be more effectively studied in other ways. Additionally, PETA says findings about mental health and mental illness in monkeys are not necessarily relevant to human brains, and none of the research being conducted has resulted in better or new treatments for human mental illnesses. Goodman said he believes these studies are "completely unjustifiable and scientifically they are absolutely fraudulent." Some independent scientists who reviewed the studies at PETA's request echoed those concerns. "I can no longer see a potential benefit from such experimentation," Agustin Fuentes, Ph.D., Chair of Anthropology at the University of Notre Dame, told the group. "It is my assessment that the monkeys used in these experiments experience substantial psychological (and likely physiological) harm and that there is no current evidence that there will be any results from the studies that move our understanding of human psychopathology forward." Suomi, however, maintains this research could prove to have great value for humans. "NIH supports studies involving monkeys to supplement the developmental studies of human beings," Suomi told CBS News. "The same behavioral, neurological and health changes seen in nursery-reared monkeys are seen in children who were orphaned from their mothers, or raised by depressed, abusive, or neglectful mothers. These findings assist researchers in identifying humans most likely to suffer negative effects in at-risk situations and develop behavioral and drug therapies to improve negative outcomes early in development." Monkey research on childhood development has a long history, and one that is closely tied to criticism by animal rights activists. In the 1950s and 60s, the late Dr. Harry Harlow, then a professor of psychology at the University of Wisconsin, pioneered monkey research that explored theories of attachment in early childhood. The methodologies used in his lab, which included forced mating of mentally disturbed monkeys and isolating baby monkeys in dark chambers for as long as a year, were partially responsible for inciting the animal cruelty debate. Perhaps ironically, the impetus for much of Harlow's research was to better understand the nature of love. PETA believes Suomi -- a former student of Harlow's -- and other researchers have continued this legacy of animal exploitation using study models similar to those used in Harlow's lab. However, in their investigation, Goodman said PETA did not attempt to contact Suomi or Averbeck to discuss the research. Dr. Constantine Stratakis, the scientific director of the NICHD, who oversees non-human primate research including that conducted by Suomi, told CBS News these studies are constantly monitored by the NIH's animal care committee and also consistently evaluated by the U.S. Department of Agriculture and the Association of Assessment and Accreditation of Laboratory Animal Care International , which is not affiliated with the NIH. Additionally, NIH scientists are required to justify why it would be necessary for their research to utilize an animal study model. He said evaluations of the labs by these agencies have not indicated animal abuse and that the scientists take exceptional care of the animals. "They have names for these babies and birthdays for the babies," said Stratakis. "It's not that different from a human nursery." PETA's investigation highlights a number of video clips obtained from the NIH, including footage of one test used to study the fright response in infants, in which a baby monkey is shown isolated in tiny mesh cage known as a "startle chamber," while researchers play loud and unexpected noises. The monkey is noticeably in distress and panicked. But Stratakis said the cages are meant to protect the safety of the monkey since a panicked animal allowed to run free is likely to injure itself in these circumstances. Stratakis added the methodologies depicted in videos are not currently used by the researchers. He said most of of the photos and videos in question are five years old; a spokesperson for the NIH said a majority of video footage obtained by PETA is from 2009. "The protocols that are ongoing right now are different from the protocols that were in effect in studies conducted shown in the video," said Stratakis. "These studies have ended and just as the nature of most of our studies, when the goals are met the studies are concluded." Stratakis added that the studies in question were initiated to observe how environmental and psychosocial factors experienced in early childhood have pervasive and long-term impact by influencing chemical reactions in the body and ultimately altering genes -- a fundamental and growing field of research known as epigenetics. A number of well received and important papers have come out of Suomi's lab, said Stratakis. One benchmark study found that babies learn better when they see faces, and that an infant's efforts to mimic parents is a critical milestone in development. Another study, published in the journal Psychoneuroendocrinology in April, looked at how population density influences cortisol levels in the body . It found that when groups of monkeys were placed in smaller spaces, their physiological stress response increased, evidenced by higher cortisol levels found in their hair. PETA asserts that researchers could gather similar data from humans using brain scans and other techniques. For their investigation, Goodman and his team consulted a number of outside experts, including world-renowned primatologist Jane Goodall and John Gluck, emeritus professor of psychology at the University of New Mexico and a research professor at the Kennedy Institute of Ethics at Georgetown University, who previously conducted similar research on social deprivation in primates. "I eventually chose to leave that area of research because I came to believe that those models did not accurately represent the development and presentation of human mental illness," said Gluck in a statement prepared by PETA. "I came to the view that those models could not adequately inform innovative directions for successful clinical intervention to justify the costs in suffering and pain. I see nothing to alter that view with respect to the program of primate deprived early experience research currently being conducted at the NIH." But Allyson Bennett, PhD , a professor in the department of psychology at the University of Wisconsin who previously worked alongside Suomi, said that human studies don't always produce consistent and reliable results. "What primate research gives you that's not possible in humans is the ability to control the environment," she told CBS News. She said studying development in infant primates allows for the consistency with factors such as food, shelter and sleep. Bennett, who is also a member of Speaking of Research , a volunteer group of scientists and advocates who seek to raise awareness about the importance of animal research, said much of this research has also benefited animals living in both captive and natural habitats by identifying ways to help them thrive in places such as animal sanctuaries and zoos. "In my experience scientists are deeply concerned about the animals they work with," said Bennet. "These are ethical and moral dilemmas all of us wrestle with." Jessica Firger covers health and wellness for CBSNews.com More from CBS News 250 COMMENTS This Guy Simultaneously Raised a Chimp and a Baby in Exactly the Same This Guy Simultaneously Raised a Chimp and ... Gua (chimpanzee) Gua (chimpanzee) Harry Harlow Monkey Experiments: Cloth Mother vs Wire Mother Harry Harlow Monkey Experiments: Cloth Mother vs Wire ... Harry Harlow and the Nature of Affection Harlow's monkey mother experiment was unethical because of the treatment of the infant monkeys. The original monkey mother experiments were unnecessarily cruel. The infant monkeys were deprived of maternal care and social contact. In later experiments, Harlow kept monkeys in total isolation in what he himself dubbed a "pit of despair." These 1950s experiments showed us the trauma of parent-child separation These 1950s experiments showed us the trauma of parent- ... Harlow's Classic Studies Revealed the Importance of Maternal Contact Harlow's Classic Studies Revealed the Importance of ... Harry Harlow Harry Harlow - Wikipedia ... Harry Harlow The 1931 experiment that paired a newborn chimp with a newborn baby The 1931 experiment that paired a newborn chimp with a newborn baby. One of the earliest experiments in primate-human similarities took place all the way back in the 1930s, when a baby chimp and a ... Harlow's Monkey Experiments: 3 Findings About Attachment Harlow's Monkey Experiments: 3 Findings About Attachment NIH Child Abuse: Experiments on Baby Monkeys Exposed PETA has obtained documents, hundreds of photographs, and more than 500 hours of never-before-seen high-definition videos taken inside this NIH facility, detailing the ongoing psychological abuse of baby monkeys in disgustingly cruel and archaic experiments that have been funded by more than $30 million just in the past seven years.. Each year, 40 to 60 monkeys are born at this NIH facility ... Inside twisted experiment where baby named Donald became 'more ape than A HUMAN baby raised alongside a chimpanzee "became more ape than human" before tragically killing himself later in life. Animal psychologists Winthrop Niles Kellogg and his wife Luella carried out a bizarre experiment in the 1930s as they raised a chimp named Gua and their son Donald as "brother and sister". Pit of despair Pit of despair Baby Monkeys at Harvard Are Separated From Their Mothers ... Margaret Livingstone, a Harvard University experimenter, has spent her entire 40-year career tormenting animals. Her experiments involve removing infant monk... Harlow's Monkey Experiment Harlow believed that it is at 90 days for monkeys, and about 6 months for humans. Moreover, it was found that the establishment of bond between baby and mother is not purely dependent on the satisfaction of one's physiological needs (warmth, safety, food) , but also emotional (acceptance, love, affection). Experimental Psychology Psychology ... What scientists learned when they tried to raise a chimp with a human baby FACT: You can't raise a baby chimpanzee like a tiny human. By Purbita Saha. Brave psychology couple Winthrop and Luella Kellogg gave this experiment a go in the 1930s—and though it led to some ... Harry F. Harlow, Monkey Love Experiments These monkey love experiments had powerful implications for any and all separations of mothers and infants, including adoption, as well as childrearing in general. In his University of Wisconsin laboratory, Harlow probed the nature of love, aiming to illuminate its first causes and mechanisms in the relationships formed between infants and ... Harlow's Monkey Experiment (Definition Harlow's Monkey experiments looked at the influence of parental guidance and interaction during early development. Infant monkeys were placed in isolation, away from their mothers. In other experiments, he took infant monkeys away from their mothers but placed them in a cage with "surrogate" mothers. In both sets of experiments, he found ... Rock-A-Bye Baby Rock-A-Bye Baby - documentary from 1984. It delves into the work of Harry Harlow and his experiments on baby monkeys and the affect of losing mother or not h... Cruel Experiments on Infant Monkeys Still Happen All the Time--That Raised in total or partial social isolation, clinging desperately to wire or cloth "mothers," rhesus monkey infants subjected to American psychologist Harry F. Harlow's maternal-deprivation ... Baby Monkey Experiments Exposed Subscribe to #PETA: https://bit.ly/2Qu3mOO 🔔Turn on ALL push notifications 🔔VICTORY: Following an intensive yearlong PETA campaign, the National Insti... Is animal testing effective? The limits of lab monkey experiments ... Housing for monkeys is tight. The standard cage for a rhesus macaque, a common laboratory primate, is about 2.5 feet across, narrow enough for its inhabitant to touch both walls at once. By ... Still Now, Should Lab Monkeys Be Deprived Of Their Mothers? Many people know about Harry Harlow's maternal-deprivation experiments with monkeys from the 1950s. Harlow showed us that baby monkeys collapse into depression and otherwise alter their behavior ... Questions raised about mental health studies on baby monkeys at NIH PETA's investigation highlights a number of video clips obtained from the NIH, including footage of one test used to study the fright response in infants, in which a baby monkey is shown isolated ... essay homework paper phd project resume review speech thesis