Animal Studies of Attachment: Lorenz and Harlow

In the 1950s research which used animal subjects to investigate early life experiences and the ability for organisms to form attachments contributed significantly to the field of developmental psychology. Two of the most well-known animal studies were conducted by Konrad Lorenz and Harry Harlow.

Lorenz (1952)

Lorenz’s research suggests that organisms have a biological propensity to form attachments to one single subject.

Lorenz conducted an experiment in which goslings were hatched either with their mother or in an incubator. Once goslings had hatched they proceeded to follow the first moving object that they saw between 13 & 16 hours after hatching; in this case, Lorenz.

It supports the view that having a biological basis for an attachment is adaptive as it promotes survival.

This would explain why goslings imprint after a matter of minutes due to their increased mobility; human babies are born immobile and therefore there is less call for them to form an attachment straight away, and so, this develops later (8-9 months).

Harlow (1958)

Harlow conducted research with 8 rhesus monkeys which were caged from infancy with wire mesh food dispensing and cloth-covered surrogate mothers, to investigate which of the two alternatives would have more attachment behaviours directed towards it.

Harlow measured the amount time that monkeys spent with each surrogate mother and the amount time that they cried for their biological mother.

Harlow’s findings revealed that separated infant rhesus monkeys would show attachment behaviours towards a cloth-covered surrogate mother when frightened, rather than a food-dispensing surrogate mother. Monkeys were willing to explore a room full of novel toys when the cloth-covered monkey was present but displayed phobic responses when only the food-dispensing surrogate was present.

Furthermore, Harlow reviewed infant monkeys that were reared in a social (non-isolated) environment and observed that these monkeys went on to develop into healthy adults, while the monkeys in isolation with the surrogate mothers all displayed dysfunctional adult behaviour, including:

a) Being timid

b) Unpredictable with other monkeys

c) They had difficulty with mating

d) The females were inadequate mothers

Implications of Animal Studies of Attachment

Lorenz (1952)

The fact that the goslings studies imprinted irreversibly so early in life, suggests that this was operating within a critical period, which was underpinned by biological changes. The longevity of the goslings’ bond with Lorenz would support the view that, on some level, early attachment experiences do predict future bonds. The powerful instinctive behaviour that the goslings displayed would suggest that attachments are biologically programmed into species according to adaptive pressures; goslings innately follow moving objects shortly after hatching, as this would be adaptive given their premature mobility.

Harlow (1958)

The rhesus monkeys’ willingness to seek refuge from something offering comfort rather than food would suggest that food is not as crucial as comfort when forming a bond. The fact that isolated monkeys displayed long-term dysfunctional behaviour illustrates, once more, that early attachment experiences predict long-term social development. Despite being fed, isolated monkeys failed to develop functional social behaviour, which would suggest that animals have greater needs that just the provision of food.

Evaluating Animal Studies of Attachment

Strengths

Humans and monkeys are similar

Green (1994) states that, on a biological level at least, all mammals (including rhesus monkeys) have the same brain structure as humans; the only differences relates to size and the number of connections.

Important practical applications

Harlow’s research has profound implications for childcare. Due to the importance of early experiences on long-term development, it is vital that all of children’s needs are catered for; taking care of a child’s physical needs alone is not sufficient.

Weaknesses

Results cannot be generalised to humans

It is questionable whether findings and conclusions can be extrapolated and applied to complex human behaviours. It is unlikely that observations of goslings following a researcher or rhesus monkeys clinging to cloth-covered wire models reflects the emotional connections and interaction that characterises human attachments.

Research is unethical

The use of animals in research can be questioned on ethical grounds. It could be argued that animals have a right not to be researched/ harmed. The pursuit of academic conclusions for human benefits could be seen as detrimental to non-human species.