Animal studies of attachment: Lorenz and Harlow.

What this dot point is asking

AQA wants you to describe Lorenz's and Harlow's animal studies of attachment and what they show about how attachment forms. The exam skill is to report the procedures and findings accurately and to use them to argue against learning theory, while handling the issue of generalising from animals to humans with care.

Lorenz

Lorenz's procedure is worth knowing in detail because exam questions ask you to outline it. He randomly divided a clutch of goose eggs: half hatched with their natural mother and half hatched in an incubator with Lorenz present. The incubator goslings imprinted on Lorenz, following him everywhere, while the naturally hatched group followed their mother. To confirm the effect, he marked the two groups and placed them together under an upturned box; when released, each group went to its own "mother". He argued imprinting could only occur within a narrow critical period (a few hours, and certainly within the first two days) and that, once formed, it was irreversible. He also reported sexual imprinting, where birds that had imprinted on a non-natural object later directed courtship behaviour towards that type of object as adults. Lorenz's work introduced the idea, later taken up by Bowlby, that attachment is innate, time-limited and adaptive rather than learned through feeding.

Harlow

Harlow (1958) raised infant rhesus monkeys with two surrogate "mothers": a wire one that dispensed milk and a soft cloth-covered one.

The power of Harlow's design is that it pitted food against comfort directly: if learning theory were right, the monkeys should have attached to the wire mother that fed them. Instead they sought the cloth mother for comfort and used her as a secure base, fleeing to her when a frightening mechanical object was introduced. The long-term follow-up is equally important: monkeys reared with surrogates (or in isolation) grew up socially and sexually dysfunctional, were aggressive, and as mothers neglected or attacked their own young, and Harlow found there was a critical period of about 90 days after which damage from deprivation was largely irreversible. This gives the study real explanatory value for later topics such as maternal deprivation, but it also raises severe ethical issues, since the monkeys suffered lasting psychological harm, and questions about generalising findings from monkeys to humans.