Neural and Hormonal explanations of aggression

Low levels of serotonin in the pre-frontal cortex=amygdala to be more stimulated by external events=more impulsivity+aggression

Mann et Al (1990)-35 male, healthy Ps drug called dexfenfluramine=decreases serotonin levs.
-took drug+did questionnaire on hostility+agg, and it was found that agg levs increased after drug treatment-supports serotonin influencing agg.
-Small, male sample-low val-beta bias-low serotonin might affect women differently
-Self report technique-demand characteristics-helping the experimenter-decreasing internal val

Raleigh-supporting
-monkeys on diet of tryptophan (high serotonin) they were less agg than monkeys not on diet- supports as change in serotonin changed agg beh. 
-lacks external val, as done on animals and so cannot be extrapulated onto humans-they might not have same bio mechs as us! also, the damage to their physical health is difficult to justify when the results cant even be used on humans 

High levs of dopamine cause agg beh

Supporting evidence comes from:
Buitelaar et al (2003)-dopamine antagonists reduced agg beh-signpost
But there is little else conclusive evidence
Couppis+Kennedy- not supporting-actually found that dopamine is a result of agg- a reward pathway is stimulated when we are agg where dopamine is positive reinforcer--it doesnt explain agg and is an effect

Testosterone is a hormone which influences agg-influences areas of the brain that control behavioural actions, eg amygdala+hypothalamus

Archer (1991) supporting study-meta analysis of 230 males over 5 studies=positive correl between testosterone levs and agg beh-signpost
-correlational and so cannot determine cause/effect

Dabbs et al supporting-measured salivary testosterone levs in violent and non-violent criminals -those w high testosterone had the more violent histories-signpost

Gender bias in studies linking testosterone to agg-mainly look at men bc it is a male sex hormone-beta bias. Maybe we should research on women as some research as shown link between female testosterone+agg-maybe this area needs more focus

Biological explanation is reductionist-complex behaviours down to neurotransmitters and hormones, no psych factors

Deterministic-if you have low levs of serotonin or high levs of testosterone inevitably agg? Free will must play a part.

Biological explanation is reductionist-complex behaviours down to neurotransmitters and hormones, no psych factors

Deterministic-if you have low levs of serotonin or high levs of testosterone inevitably agg? Free will must play a part.