Flashcards in Sex Differences (2) 4 Deck (9)
What is the name of the characteristic posture of the female to allow mating?
What was found in the key experiment on guinea pigs (Phoenix et al. 1959)?
Females treated with testosterone as embryos at both doses (high and low) showed increased frequency of mounting and decreased frequency of lordosis
But male behaviours were not affected
What is an organising effect?
Exposure to hormones early in life leads to the organisation of the brain causing a change in behaviour
Exposure to androgens early in life permanently organises the brain to express male behaviour in adulthood
Give an example of an activational effect?
When the males are castrated so do not show male behaviour, they are then injected with male hormones and demonstrate male behaviours
What converts testosterone to an oestrogen in the male and female brain?
What are brain areas regulating reproductive behaviour rich in?
Aromatase and oestrogen receptors
What was found in the ovary transplant experiments by Pfeifer in the 1930s?
Male rats castrated at 1 and 20 days old and implanted with ovaries
Female cycles observed after early but not late castration
Thus an organisational effect was present
What area of the brain is important in controlling the sexual behaviour of an animal?
The medial preoptic area (MPOA)