Harlow's animal study

Harlow's animal study

1. Harry Harlow worked with rhesus monkeys, which are much more similar to humans than Lorenz's birds, to understand how they attach.

   • Harlow's findings have had a profound effect on psychologists' understand of human mother-infant attachment. He showed that attachment does not develop as the result of being fed by a mother figure but as a result of contact comfort. Harlow also showed us the importance of the quality of early relationships for later social development including the ability to hold down adult relationships and successfully rear children.
   • Harlow's research has helped social workers understand risk factors in child neglect and abuse and so intervene to prevent it. It is also important in the care of captive monkeys, now understanding the importance of proper attachment figures for baby monkeys in zoos and also in breeding programmes in the wild.
   • Harlow faced severe criticism for the ethics of his research . Monkeys suffered greatly as a result of his procedures. This species is considered similar enough to humans to be able to generalise the findings, which also means that their suffering was presumably quite human-like. Harlow himself was aware of the suffering caused - referring to the wire mothers as iron maidens after the medieval torture device. The counter argument is that is research was sufficiently important to justify the effects.

2. The important of contact comfort

   • Harlow observed that newborns kept alone in a bare cage usually died but that they usually survived if given something soft like a cloth to cuddle.
   • Harlow (1958) tested the idea that a soft object serves some of the functions of a mother.
     • He reared 16 baby monkeys with two wire model mothers.
       • In one condition milk was dispensed by the plain wire mother whereas in the second condition the milk was dispensed by the cloth-covered mother.
   • It was found that the baby monkeys cuddled the soft object in preference to the wire one, soughting comfort from the cloth one when frightened, regardless of which dispensed milk.
     • This showed that contact comfort was of more important to the monkeys than food when it came to attachment behaviour.

3. Maternally deprived monekys as adults

   • Harlow and colleagues also followed the monkeys who had been deprived of a real mother into adulthood to see if this early maternal depriviation had a permanent effect. Researchers found severe consequences.
   • The monekys reared with wire mothers only were the most dysfunctional. However, even those reared with a soft toy as a substitute did not develop normal social behaviour.
     • They were more aggressive and less sociable than other monkeys.
     • They bred less often than is typical for monkeys, being unskilled at mating.
     • When becoming mothers themselves, some of the deprived monkeys neglected their young and others attacked their children, even killing them in some cases.

4. The critical period for normal development

   • Harlow concluded that there was a critical period for this behaviour - a mother figure had to be introduced o an infant monkey within 90 days for an attachment to form.
     • After this time attachment was impossible and the damage done by early deprivation became irreversible.