AQA A Level Psychology复习笔记3.2.2 Lorenz & Harlow

Lorenz (1935)

• Lorenz was an ethologist who looked at the phenomenon of Imprinting in goslings.
• Imprinting is the idea that some species attach to the first moving object they see when they are born.
• This is often found in most species of birds, particularly ducks and geese.
• The idea was that if baby animals can attach after such a short space of time: Literally in seconds, then attachment must be innate.
• It is a quality that these animals are born with, posing the question is it innate in humans.

The Study on imprinting

• Lorenz took a batch of 12 fertilised geese eggs and split them into two groups of six
• One group (the control group) remained with the mother until they hatched
• The second/experimental group was placed into an incubator and Lorenz stayed close when they were due to hatch
• He was to be the first moving object they saw
• It was later observed that if you mixed the two groups they would automatically split into their original groups
• The 'Lorenz goslings' were observed to follow him everywhere
• Even as adults the goslings still sought out Lorenz as their 'mother'

Evaluation of Lorenz

• Lorenz does support the idea of a critical period as he found the goslings needed to imprint within 30 hours or an attachment would not be possible
• This will later support Bowlby's idea of the human infant's critical period of 30 months
• However, humans are more complex compared to goslings and so attachment is not likely to be such a quick process in humans: Birds have different survival requirements and develop into maturity much faster than a human
• Human attachment needs to take longer as often the mother cannot be with the baby for several hours, days, or even weeks due to the nature of human childbirth and the impact it has on the health and wellbeing of the mother
• However, wherever possible the mother is encouraged to hold the infant as soon as possible after giving birth to encourage development to begin
• The study has high ecological validity as it was a field study
• It is also highly reliable and has been repeated both experimentally as well as noted anecdotally (the duckling who has made a puppy her mother in China is especially cute!)
• However, small sample sizes do limit how far we can generalise the results

Harlow: Love in infant monkeys (1958)

• Harlow wanted to look at how infant rhesus monkeys attached to their mothers.
• He conducted a classic, if not controversial study into this.

The study of love in infant monkeys

• Baby rhesus monkeys were taken from their mothers as soon as they were born
• They were then placed in a cage with two 'surrogate mothers': One made of comfortable, terry cloth and one made of wire
• The wire mother had a bottle of milk inside of it so the monkey could feed on her
• It was observed how long the monkey spent with each 'mother'
• The monkeys tended to spend most of their time with the cloth mother, only going to the wire mother to feed
• If the baby monkey was frightened it would immediately cling to the cloth mother for support
• They also used the cloth mother as a safe space to explore the cage
• From this Harlow et al concluded that infants needed comfort more than food for attachment

Evaluation

• Incredibly influential in how we saw infant-caregiver relationships
• The monkeys raised in that experiment suffered psychological damage from being without an adequate primary caregiver that proved to be irreparable in adulthood: They often self-harmed and could not attach to their own offspring
• This highlighted the need for a 'responsive' caregiver
• However, due to these developmental issues, the experiment is highly unethical
• It caused immense psychological harm to the infant monkeys, that could never be repaired
• There are also questions about validity: Is this really attachment?
• Attachment is complex, linked to a range of emotions and biological needs: Was Harlow really seeing 'love' for a cloth mother in this experiment
• If he was not, then the experiment is not really about attachment/love and so is not valid
• It is also not reliable as it can never, nor should be, repeated

Overall evaluation of animal studies

• How much can we apply this to human infants?
• There will clearly be differences in species and it would be wrong to generalise to human infants without more evidence
• However, some would argue that monkeys are similar to humans in that we have similar neurological structures, therefore some inference is possible (Green 1994)
• The implications of both studies are important, especially Harlow: He disputes learning theory as an explanation and really shows the importance of the PCG role
• Lorenz also support the evolutionary explanation as it highlights attachment must be innate (at least in some species- so why not humans?)