Harlow

• Monkeys spent most of their time with the cloth-covered monkey, showing a preference for contact comfort
• Harlow's research has been criticized for being unethical and of limited value in understanding the effects of deprivation on human infants
• Harlow studied attachment in rhesus monkeys by providing two wire monkeys, one cloth-covered and one plain, to infant monkeys
• Harry Harlow wanted to study the mechanisms by which newborn rhesus monkeys bond with their mothers
• Infants depended highly on their mothers for nutrition, protection, comfort, and socialization
• 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 conducted experiments on attachment in rhesus monkeys during the 1950s and 1960s
• Cloth Mother vs. Wire Mother Experiment:

  • Infant monkeys were separated from their mothers and placed in cages with two surrogate mothers: one made of wire and one covered in soft terry toweling cloth
  • Infants spent more time with the cloth mother, even if she had no milk
  • When hungry, the infant would go to the wire mother for food but return to the cloth mother for comfort
  • The cloth mother served as a "safe base" for the infant, reducing fear and promoting exploration
• Monkeys who had soft, tactile contact with their terry cloth mothers behaved differently than those with wire mothers:

  • They were more timid
  • They had difficulty with mating
  • The females were inadequate mothers
  • These behaviors were observed in monkeys left with surrogate mothers for more than 90 days
• Rhesus Monkeys Reared in Isolation:

  • Harlow isolated babies from birth for different durations
  • When placed back with other monkeys, they engaged in bizarre behavior such as self-mutilation and aggression
  • Those isolated for longer periods showed more severe effects
• Conclusions:

  • Mother-infant emotional bonds result primarily from comfort and tactile contact
  • Early maternal deprivation leads to emotional damage, but its impact can be reversed if an attachment is made before the end of the critical period
  • Social deprivation, rather than maternal deprivation, was found to be the cause of abnormal behavior in young monkeys
  • Interaction with an object to which they can cling during the critical period is crucial for normal development
• Impact of Harlow's Research:

  • Helped social workers understand risk factors in child neglect and abuse
  • Using animals to study attachment can benefit children at risk in society
  • Research influenced attachment theory and emphasized the importance of emotional care
• Ethics of Harlow's Study:

  • Harlow's experiments have been criticized as unethical and of limited value in understanding the effects of deprivation on human infants
  • However, the research provided valuable insights into attachment and social behavior, influencing the work of John Bowlby and emphasizing emotional care in various settings
• 𝙃𝘼𝙍𝙇𝙊𝙒'𝙎 𝙋𝙍𝙊𝘾𝙀𝘿𝙐𝙍𝙀:

  Harlow (1958) tested the idea that a soft object serves some of the functions of a mother. In one experiment he reared 16 baby monkeys with two wire model 'mothers'. In one condition the milk was dispensed by the plain-wire model whereas in the second condition it was dispensed by the cloth-covered model.
• 𝙃𝘼𝙍𝙇𝙊𝙒'𝙎 𝙁𝙄𝙉𝘿𝙄𝙉𝙂𝙎:

  The baby monkeys cuddled the cloth-covered mother in preference to the plain-wire mother and sought comfort from the cloth-covered mother when frightened, regardless of which mother dispensed milk.

  This showed that contact comfort was of more importance to the monkeys than food when it came to attachment behaviour.
• 𝙈𝘼𝙏𝙀𝙍𝙉𝘼𝙇𝙇𝙔 𝘿𝙀𝙋𝙍𝙄𝙑𝙀𝘿 𝙈𝙊𝙉𝙆𝙀𝙔𝙎:

  Harlow and colleagues also followed the monkeys who had been deprived of a real mother into adulthood to see if the early maternal deprivation had a permanent effect. The researchers found severe consequences, where the monkeys reared with plain-wire mothers were the most dysfunctional.

  However, even those reared with the cloth-covered mothers did not develop normal social behaviour. They were aggressive, less sociable, and unskilled at mating. When they became mothers, they neglected, attacked, and often killed their children.
• 𝙏𝙃𝙀 𝘾𝙍𝙄𝙏𝙄𝘾𝘼𝙇 𝙋𝙀𝙍𝙄𝙊𝘿:

  Like Lorenz, Harlow concluded that there was a critical period for attachment formation - a mother figure had to be introduced to a young monkey within 90 days of birth for an attachment to form.

  After this time, attachment was impossible and the damage done by early deprivation was irreversible.
• In Japan and South Korea robots are being designed to carry out childcare. Currently robot nannies are generally used for very short-term care with parents in easy reach, but Sharkey and Sharkey (2010) raise concerns about what might happen to children's development if children are largely raised by inanimate objects rather than human carers.

  The nearest situation we have to this is Harlow's studies in which monkeys had basic care provided by wire mothers. Monkeys raised without attachments to adults of their species became highly dysfunctional adults.
• • 𝗜𝗺𝗽𝗼𝗿𝘁𝗮𝗻𝗰𝗲 𝗼𝗳 𝗖𝗼𝗻𝘁𝗮𝗰𝘁 𝗖𝗼𝗺𝗳𝗼𝗿𝘁: Infant monkeys preferred a cloth-covered mother to a wire one regardless of which provided milk.
  • 𝗠𝗮𝘁𝗲𝗿𝗻𝗮𝗹 𝗗𝗲𝗽𝗿𝗶𝘃𝗮𝘁𝗶𝗼𝗻: Monkeys brought up without a mother were dysfunctional as adults.
  • 𝗖𝗿𝗶𝘁𝗶𝗰𝗮𝗹 𝗣𝗲𝗿𝗶𝗼𝗱: Monkeys had around 90 days to attach to a mother figure or they could not form an attachment.
• 𝗘𝗩𝗔𝗟𝗨𝗔𝗧𝗜𝗢𝗡 𝗢𝗙 𝗛𝗔𝗥𝗟𝗢𝗪:

  • real-world value
  • generalisability to humans
  • ethical issues
• (𝗛)

  𝟭. 𝗥𝗘𝗔𝗟-𝗪𝗢𝗥𝗟𝗗 𝗩𝗔𝗟𝗨𝗘:

  One strength of Harlow's research is its important real-world applications.

  For example, it has helped social workers and clinical psychologists understand that a lack of bonding experience may be a risk factor in child development, allowing them to intervene to prevent poor outcomes. We now also understand the importance of attachment figures for baby monkeys in zoos and breeding programs in the wild.

  This means that the value of Harlow's research is not just theoretical but also practical.
• (𝗛)

  𝟮. 𝗚𝗘𝗡𝗘𝗥𝗔𝗟𝗜𝗦𝗔𝗕𝗜𝗟𝗜𝗧𝗬 𝗧𝗢 𝗛𝗨𝗠𝗔𝗡𝗦:

  One limitation of Harlow's research is the ability to generalise findings and conclusions from monkeys to humans.

  Rhesus monkeys are much more similar to humans than Lorenz's birds, and all mammals share some common attachment behaviours. However, the human brain and human behaviour is still more complex than that of monkeys.

  This means that it may not be appropriate to generalise Harlow's findings to humans.
• (𝗛)

  𝟯. 𝗘𝗧𝗛𝗜𝗖𝗔𝗟 𝗜𝗦𝗦𝗨𝗘𝗦:

  Harlow's research caused severe and long-term distress to the monkeys. However, his findings have important theoretical and practical applications.

  On the one hand, Harlow's procedures were very stressful for the monkey participants. This is particularly bad as the stress was long-term, and monkeys are quite similar to humans so probably suffered to a similar extent.

  On the other hand, Harlow's research has practical applications that have benefitted large numbers of humans and animals. Therefore, it could be argued that the studies were justified.
• What can we conclude from Harlow's research?

  Monkeys have an innate, unlearned need for contact and comfort, suggesting that attachment concerns emotional security rather than food.

  Contact comfort is associated with lower levels of stress and a willingness to explore.