Psychological Explanations - Biological Explanations, Head trauma research

Head Trauma Research

The MAOA gene and the Cadherin 13 gene have also been assosicated with criminality. The MAOA gene is an enzyme that normally functions in neutronal mitochondria by breaking down several key mitochondria by breaking down several key neuronsmitters: serotonin, dopamine and norepinephrine which are important in aggression, emotion and cognition. Cadherin 13 has been linked to impluse control. Both genes are located in the Y chromosome. Lower levels of serotonin produced which can lead to difficulties controlling emotional responses to anger in the amygdala. Severe low levels of serotonin can lead to a condition called 'intermittent explosive disorder' (characterisied by sudden explosive outbursts of rage often resulting in violence). Seotonin inhibits behavioural responses to provocative events and regulates aggressive/violent actions. Lower levels of serotonin have been found in violent offenders (Linnolia et al. 1983). Low sertonin activity in man has been related to implusive, self-destructive violence but not to instrumental aggression aimed at dominance (Soderstorm et al. 2001). 

Electro Encephalographic Measures measure the elecotonic activity of the brain. Positron Emission Tomography highly localised brain activity can be measursed. This allows for reviews of whether the brain functions differently in serious criminals. Brain imaging has shown that the hippocampus shows abnormal functioning in murdrers and structural abnormalities in psychopaths.…