- Researchers took MRI brains scans of 12 violent psychopathic criminals
- These were compared to scans of other criminals and non-offenders- The psychopaths showed abnormal activity in key areas of their brains that are known to be involved in learning from punishments and rewards
- It could explain why psychopaths do not benefit from rehabilitation
According research at Kings College London, violent psychopathic criminals may be unable to learn from punishment due to abnormalities in key parts of their brain, according to a new study.
Brain scans of violent offenders have shown that those with psychopathic tendencies react differently when confronted with punishment or a negative reaction to their behavior. This could be why psychopaths do not benefit from rehabilitation programs while other violent criminals often do.
Around one in five violent offenders are thought to be a psychopath and they are known to have higher rates of reoffending.
The researchers behind the latest study hope that their findings could help to develop new interventions in childhood that could reduce the risk of violence and reoffending. The scientists found that the psychopaths had reduced levels of grey matter and abnormal white matter in areas of the brain that are involved in learning from rewards and punishment.
Dr Nigel Blackwood, a psychologist at Kings College London, said: 'Psychopathic offenders are different from regular criminals in many ways.
'Regular criminals are hyper-responsive threat, quick-tempered and aggressive, while psychopaths have a very low response to threats, are cold, and their aggressively is premeditated. 'Evidence is now accumulating to show that both types of offenders present abnormal, but distinctive, brain development from a young age.
'We found that the violent offenders with psychopathy, as compared to both the violent offenders without psychopathy and the non-offenders, displayed abnormal responses to punishment within the posterior cingulate and insula when a previously rewarded response was punished.'
The researchers, whose work is published in the journal Lancet Psychiatry, conducted MRI scans on 12 male violent psychopathic criminal offenders and 20 male violent offenders without psychopathy from the UK.
The men had all been convicted of murder, rape, attempted murder and grevious bodily harm and were recruited from the probation service. They were asked to complete a task that involved matching pairs of images of animals or furniture displayed on a screen when they were in the scanner.
Each choice gained them or lost them points depending on their answer. The researchers then assessed what happened when they changed the rules of the game, removing points for answers that would have once won them points and vice versa.
The same test was also conducted on 18 healthy non-offenders.
Dr Blackwood said: 'When these violent offenders completed neuropsychological tasks, they failed to learn from punishment cues, to change their behavior in the face of changing contingencies, and made poorer quality decisions despite longer periods of deliberation.'
The scans also revealed the psychopaths had abnormal brain responses in the posterior cingulate and insula parts of the brain that are involved in reward and punishment learning. The scientists believe their results could be used to help produce new treatments for violent offenders, particularly for those with psychopathy.
'Our results also provide hypotheses about the abnormal development of violent offenders to be tested in studies of children.' Professor Sheilagh Hodgins, from the University of Montreal who was also involved in the study, said learning from punishment was an important part of regulating behavior.
She said: 'Offenders with psychopathy may only consider the possible positive consequences and fail to take account of the likely negative consequences.
'Consequently, their behavior often leads to punishment rather than reward as they had expected. 'Punishment signals the necessity to change behavior. Clearly, in certain situations, offenders have difficulty learning from punishment to change their behavior.'
She added: 'Since most violent crimes are committed by men who display conduct problems from a young age, learning-based interventions that target the specific brain mechanisms underlying this behavior pattern and thereby change the behavior would significantly reduce violent crime.'
Source: mail online