Nature or Nurture
The age-old debate of ‘nature versus nurture’, of how much our personality and behaviours are shaped by biology or our environment, is sharpening up as scientists’ exploration of the human brain gets ever more sophisticated. A team of researchers at the Institute of Psychiatry at King’s College London have extended the debate with a brain study of people with psychopathic personality disorder.

Dr Michael Craig, who works in a section of the Institute focussing on brain maturation, says they are particularly interested in understanding the biological underpinning of mental disorders. Using brain imaging they look at the structure and function of the brain. ‘The research to date,’ he says, ‘has reported that there are two main brain regions that appear to be different or abnormal in people with psychopathy. Those two regions are the Orbital Frontal Cortex (OFC), which is at the front of your brain, and another region called the Amygdala. The OFC is associated with decision-making, impulse control, and the Amygdala is involved with processing emotions.’

Connections between brain regions
What nobody had looked at until now was ‘the communication’ between those two areas. ‘The way neuropsychiatry is going,’ says Dr Craig, ‘and the research I’m involved with, tries to understand the connections between different regions of the brain, not just looking at regions as being individual things.’ Dr Craig and the team compared a ‘tract’ in the brain, the Uncinate Facisculus, in a small group suffering from psychopathic personality disorder, to that of a control group. They discovered that there were differences in the anatomy of that tract between the two groups. And confirming their discovery, there wasn’t ‘a broad abnormality across the brain, it was something quite specific to the two regions that had previously been identified as being abnormal.’

Cause or effect?
The questions to be addressed next according to Craig are firstly, whether this finding can be replicated in a larger study. And secondly, ‘if we can replicate it, is this a cause or an effect of psychopathy?’ he says. ‘We know that people who have psychopathic personality disorder are going to engage in behaviour that’s different to people who are not psychopaths. Is it something about that behaviour that leads to abnormalities? Or are these abnormalities something that contributes to this behaviour?’