Biological explanations of aggression Brain structure

Learning objectives Evaluate the contribution of research into neural influences on behaviour.

The hypothalamus Bard & Mountcastle (1953) Looked at ‘rage’ in cats caused by detaching the hypothalamus from the cortex.

Flynn 2006 Stimulation of the lateral hypothalamus in cats made predatorial aggression more likely. Stimulation of the medial hypothalamus led to ‘vicious attack behaviour’.

The amygdala

Zagrodzka et al. (1998) Damage to the central nucleus of the amygdala in cats led to ‘predator-like’ attacks. Potegal (1991) hamsters have more active neurons in and around the medial nucleus of the amygdala during acts of aggression but no increases in other areas.

The amygdala In humans, if an amygdalectomy is carried out, violent behaviour is reduced, but emotions are lost.

Aggression and brain structure Two areas of the brain specifically thought to be involved in aggressive behaviour.

Phineas Gage