Zusammenfassung der Ressource
neural and hormonal mechanisms in aggression
- neural mechanisms
- limbic system
- central part of brain
- involved in processing emotional responses
- amygdala
- influences aggression in humans and animals
- causes aggressive response when stimulated
- abnormalities (eg. tumour, damage or atypical development)
- levels of testosterone can be raised
- aggressive behaviour is more likely
- research
- summer
- case study of 14-year-old girl with highly aggressive behaviour and epileptic seizures
- shown to have a tumour in the limbic system
- the patient returned to normal aggression levels after the tumour was treated with drugs
- kluver and bucy
- removed part of the temporal lobes in rhesus monkeys
- destroyed amygdala
- lower levels of aggression
- kluver-bucy syndrome
- serotonin
- inhibitory neurotransmitter
- low levels of serotonin = higher levels of aggression
- research
- cherek
- when men take drugs that increase serotonin levels = low levels of aggression
- shows low levels of serotonin = high levels of aggression
- evaluation
- :) evidence to support
- delgado - found monkeys attacked other monkeys when the hypothalamus (part of limbic system) was stimulated
- similar results with cats
- :( hard to establish cause and effect relationship
- the limbic system is made up of many different parts
- unclear which parts are involved in aggression
- could be an interaction between multiple components, not just one
- :( individual differences
- not everyone is aggressive despite having low levels of serotonin
- can't say everyone will react in the same way
- hormonal mechanisms
- testosterone
- male sex hormone
- thought to influence aggression from young adulthood onwards
- due to action on brain areas involved in controlling aggression
- higher levels lead to increased aggression
- research
- beeman
- castrated male mice
- aggressiveness reduced
- then re-injected testosterone into the mice
- aggressiveness re-established
- dolan
- found a positive correlation between testosterone levels and aggressive behaviours
- sample of 60 male offenders in UK maximum security hospitals
- evaluation
- :) evidence to support
- dabbs - found higher levels of testosterone in violent offenders than in
non-violent offenders
- violent
- rapists
- non-violent
- burglars
- thieves
- measured saliva from 692 adult male prisoners
- :( animal research
- :) it's unethical to castrate human males to lower their testosterone levels
- physical and psychological harm
- :( unethical to do conduct research on animals too
- :( problems generalising findings from animals to humans
- humans are more complex
- testosterone may differ from animals to humans
- :( research on hormonal mechanisms and aggression is correlational
- :) more ethical way to research hormonal mechanisms in aggression
- unethical to make someone aggressive by changing their level of testosterone
- :( unsure whether abnormality with hormones causes aggression or if a person being aggressive changes their hormonal structure
- :( may be other factors affecting aggression
- eg. upbringing
- :( hormonal and neural mechanisms are deterministic
- our aggression is predetermined
- :) can make predictions about aggressive behaviour
- earlier treatments can be given to prevent future aggressive behaviour
- :( not everyone responds in the same way to high levels of testosterone or low levels of serotonin
- :( ignores free will