Animal studies

• Why use animal studies?

  • practical - breed faster - results through several generations faster - cheaper than humans - easier to carry out
  • Control over animals environments, conditions in which they in, conditions of the experiments - unwanted influences can't affect findings
• Imprinting:

  • Rapid learning that occurs durng brief receptive period (typically soon after birth/hatching) and establishes a long-lasting behavioural response to a specific individual/object
  • Instinctive
  • (Lorenz's research)
• Procedure: (Lorenz)

  • Randomly divided large clutch of goose eggs
  • Half the eggs were hatched with mother in natural environment
  • Other half hatched in an incubator where first moving object they saw was Lorenz
  • Each gosling was marked to know which hatched with mother and which with Lorenz
  • Placed in box together
• Findings: (Lorenz)

  • Incubator group followed Lorenz
  • Control group (hatched with mother) followed her
  • When 2 groups were mixed up the same still happened
  • This phenomenon is called imprinting
  • Lorenz found that if imprinting does not occur within critical period then chicks did not attach themselves to a mother figure
• Sexual imprinting: (Lorenz)

  • investigated relationship between imprinting and adult male preferences
  • Birds that imprinted on a human later develop courtship behaviour towards human
  • (1952) Peacock that had been reared in reptile house of a zoo where first moving object they saw were giant tortoise
  • As adult, peacock would only direct courtship behaviour towards giant tortoises - which meant had gone under sexual imprinting
• Evaluation of Lorenz:

  • Generalisability to humans may be inappropriate as humans are much more complex as mammalian attachment system is different to birds
  • Guiton et al (1966) showed chickens who imprinted on yellow washing up gloves would try to mate with them, as predicted, but learned later to prefer mating with other chickens - impact of imprinting behaviour is not as permanent as Lorenz suggested
• Harlow carried out animal research using rhesus monkeys. This informed us about human attachment much more as they are more similar to humans than Lorenz's birds.
• Harlow observed that new-borns kept alone in a bare cage often died but usually survived if given something soft like a cloth to cuddle (contact comfort)
• Procedure: Harlow

  • one experiment, reared 16baby monkeys with 2 wired mothers. In one condition milk was dispensed by plain-wired mother, whereas in a second condition the milk was dispensed by cloth covered mother.
• Findings: Harlow

  • Baby monkeys sought cloth covered mother in preference to the plain-wire mother
  • Sought comfort from the cloth one when confronted regardless of which dispensed milk
  • This showed that 'contact comfort' was more of an importance to monkeys than food when it comes to attachment behaviour.
• Harlow and colleagues followed the monkeys who had been deprived of a 'real mother' into adulthood to see if this early maternal deprivation had a permanent effect.

  • most dysfunctional were reared with plain wired mother and were more aggressive than other monkeys
  • Bred less than typical as they were unskilled
  • When became mothers some deprived monkeys neglected their young, some attacked, some killed
• Like Lorenz, Harlow concluded that there was a critical period for attachment formation
• Evaluation of Harlow:

  • Findings very important in dev of understanding of human mother-infant attachment, in that its not result of being fed, but by contact comfort
  • Also showed importance of quality of early relationships for later social dev.
• Evaluation of Harlow

  • Findings cant be generalised
  • ethical issues