hormonal mechanisms in aggression AO1 Flashcards
what is testosterone?
a hormone from the androgen group (group of sex hormones that give men their ‘male’ characteristics) that is produced mainly in the male testes and in smaller amounts in the female ovaries.
what have many people observed about men?
many people (not just researchers) have observed that men are generally more aggressive than women.
when do men become more aggressive?
men become more aggressive towards other men at a time in development (after age of 20 years) when testosterone levels are highest (daly and wilson 1988)
testosterone has a role in regulating social behaviour via its influence on certain areas of the brain implicated in aggression.
what have castration studies of animals shown?
that removing the testes (the source of testosterone) reduces aggressive behaviour in the males of many species. giving injections of testosterone to the same animals restores aggressive behaviour (e.g giammanco et al 2005)
what did dolan et al investigate?
some evidence for a similar association as castration studies of animals in humans comes from a study of prison populations, for example violent offenders. (dolan et al)
what did dolan et al find?
- dolan et al (2001) found a positive correlation between testosterone levels and aggressive behaviours in a sample of 60 offenders (men) in uk maximum security hospitals.
- these men mostly had personality disorders (psychopathy) and histories of impulsively violent behaviour.
what is progesterone?
a female ovarian hormone which plays an important role in aggression in women.
when do levels of progesterone vary?
during the ovulation cycle and are lowest during and just after menstruation.
what did ziomkiewicz et al (2012) find?
- a negative correlation between progesterone levels and self-reported aggression.
- this suggests that low levels of progesterone are linked to increased aggression in women.
