Hormonal Mechanisms in Aggression

Question 1

what are the main aspects of the hormonal mechanisms in aggression?

Answer 1

• testosterone
• progesterone

Question 2

what is testosterone?

Answer 2

• male sex hormone
• androgen responsible for the development of masculine features

Question 3

what is testosterone linked to?

Answer 3

aggressive behaviour
- many people have observed that men are generally more aggressive than women
- has a role in regulating social behaviour by its influence on certain areas of the brain implicated in aggression

Question 4

what did Daly and Wilson say?

Answer 4

• men become more aggressive towards other men at a time in development (after 20 years) when testosterone levels are highest

Question 5

what studies involve animals and testosterone?

Answer 5

• castration studies of animals show that removing the testes reduces aggression in the males of many species
• giving injections of testosterone to the same animals restores the aggressive behaviour
  = Giammanco et al

Question 6

what did Dolan et al find?

Answer 6

• human studies of prison populations (e.g. violent offenders)
• found a positive correlation between testosterone levels and aggressive behaviours in a sample of 60 male offenders in UK maximum security hospitals
• these men mostly had personality disorders such as psychopathy and histories of impulsively violent behaviour

Question 7

what is progesterone?

Answer 7

• female sex hormone
• plays an important role in aggression in women

Question 8

how do progesterone levels change?

Answer 8

• vary during ovulation cycle and are lowest during and just after menstruation

Question 9

what did Ziomkiewicz et Al find?

Answer 9

• found a negative correlation between progesterone levels and self-reported aggression
• this suggests that low levels of progesterone are linked to increased aggression in women

Question 10

what are the evaluations for hormonal mechanisms in aggression?

Answer 10

• strength = support from research with non-human animals
• limitation = mixed evidence of the link between testosterone and aggression

Question 11

what is a strength of the hormonal mechanism of aggression?

Answer 11

• research support with non-human animals
• Giammanco et al reviewed studies to confirm the role of testosterone
• male rhesus macaque monkeys = increase in both testosterone levels and aggressive behaviour during the mating season
• rats = castration of males reduces testosterone and mouse-killing behaviour
• injecting female rates with testosterone increases mousse-killings
  = findings show role of testosterone in a range of animal species

Question 12

what is a limitation of the hormonal mechanism of aggression?

Answer 12

• mixed evidence of the link between testosterone and aggression in humans
• Carre and Mehta developed dual-hormone hypothesis to explain why
• they claim high levels of testosterone lead to aggressive behaviour but only when levels of cortisol are low
• cortisol is high = testosterone’s influence on aggression is blocked
• cortisol plays a central role in the body’s response to chronic stress
  = combined activity of testosterone and cortisol may be a better predictor of aggression than either hormone alone