Animal Studies of Attachment

• Lorenz: Imprinting

  Procedure- set up as a classic experiment, randomly dividing a large clutch of goose eggs where half the eggs were hatched with the mother in their natural environment, and the other half hatched in an incubator where the first moving object seen was Lorenz.
• Lorenz: Imprinting

  Findings- the incubator group followed Lorenz everywhere, whereas the control group followed their mother. When the 2 groups were mixed, they both consistently followed the same individual as they did prior.
• Lorenz: Imprinting

  Findings demonstrated the phenomenon of imprinting- bird species that are mobile from birth, attach to and follow the first moving object they see. Lorenz claimed that there was a critical period in which imprinting had to occur; depending on the species it was as brief as a few hours after hatching. If this doesn't occur, then they didn't attach themselves to a mother figure.
• Lorenz: Sexual Imprinting

  Lorenz also looked at the relationship between imprinting and adult mate preferences- observing that birds that had imprinted onto humans would display courtship behaviour towards humans. In his case study, a peacock was reared in a reptile house where the the first moving object seen was a giant tortoise- it then only displayed courtship behaviour towards the tortoises- the peacock had undergone sexual imprinting.
• Lorenz: AO3- Research Support

  A study by Regolin and Vallortigara supports Lorenz's idea of imprinting- chicks were exposed to moving shape combinations; after a range of shape combinations then moved in front of them, they then followed the original shape most closely. Supporting the view that young animals are born with an innate mechanism to imprint on a moving object in a critical period of development, predicted by Lorenz.
• Lorenz: AO3- Generalisability to Humans

  The mammalian attachment system is quite different and more complex than that of birds. In mammal's attachment is a two-way process, so it then isn't just the young who become attached to the mothers (like chicks). Mothers also show an emotional attachment to their young.
• Lorenz: AO3- Theory of Sexual Imprinting Questioned

  Research by Guition et al found that chicks who imprinted on yellow washing gloves would try to mate with them as adults (as predicted), but with experience they eventually learned to prefer mating with other chickens. Implying the impacts of imprinting aren't permanent as Lorenz believed.
• Harlow: Contact Comfort

  Procedure- Harlow tested the idea that a soft object serves some of the functions of a mother; after rearing 16 monkeys with 2 wire model 'mothers'- one condition had milk dispensed by a plain-wire mother, the second had the milk dispensed by a cloth-covered mother.
• Harlow: Contact Comfort

  Findings- the baby monkeys cuddled the cloth-covered monkey in preference to the plain wire monkey, and sought comfort from the cloth monkey when frightened regardless of which mother dispensed the milk in that condition. This shows that 'contact comfort' was more important to monkeys than food when it came to attachment behaviour.
• Harlow: Maternally Deprived Monkeys as Adults

  Harlow followed monkeys who had been deprived of a 'real' mother to see if early maternal deprivation had a permanent effect; researchers found several consequences. Monkeys reared by only plain-wire mothers were the most dysfunctional. Though all didn't develop normal social behaviour- more aggressive and less sociable, bred less often (unskilled at mating). When they became mothers, they were neglectful and violent to their offspring.
• Harlow: Critical Period for Normal Development

  Mother figure had to be introduced to a young monkey within 90 days for an attachment to be formed. After this time, attachment was impossible and the damage done by early deprivation became irreversible.
• Harlow: AO3- Real-World Value

  A strength of Harlow's research is that it has helped social workers and clinical psychologists understand that a lack of bonding experience may be a risk factor in a child's development- allowing them to intervene to prevent poor outcomes (Howe). We can also understand the importance of attachment figures for baby monkeys in zoos and breading programmes in the wild. Meaning the research isn't only theoretical, it is practical.
• Harlow: AO3- Generalisability to Humans

  A limitation is our ability to generalise conclusions about contact comfort; though rhesus monkeys are much more similar to humans than Lorenz's birds, all mammals do share common attachment behaviours. However the human brain and behaviour is still more complex than that of monkeys. Findings may then be not appropriate to generalise.
• Harlow: AO3- Ethical Issues

  Harlow faced severe criticism for the ethics of his research; the monkeys suffered greatly as a result of Harlow's procedures. This species is considered similar enough to humans to be able to generalise findings, which also means their suffering was presumably quite human-like. Though the counter-argument is that Harlow's research was sufficiently important which justifies its later effects.
• Harlow: AO3- Theoretical Value

  Harlow's findings have had a profound effect on psychologists' understanding of human mother-infant attachment. Most importantly, Harlow demonstrates that attachment doesn't develop as a result of being fed, it is contact comfort instead. This then demonstrates the importance of the quality of early relationships for later social development- including the ability to hold down adult relationships and rear children successfully.