A new MRI study has revealed that psychopathic violent offenders may be unable to learn from punishment due to the presence of abnormalities in their brains.
The study, published in Lancet Psychiatry, shows that abnormalities can be found in the areas of the brain associated with learning from punishment. These abnormalities were not found in the brains of non-psychopathic violent offenders or non-offenders, a finding that may explain why psychopaths do not benefit as much from rehabilitation programs.
“One in five violent offenders is a psychopath,” says study author Dr. Sheilagh Hodgins. “They have higher rates of recidivism and don’t benefit from rehabilitation programs. Our research reveals why this is and can hopefully improve childhood interventions to prevent violence and behavioral therapies to reduce recidivism.”
Researchers typically use the term “psychopath” to refer to individuals who display immoral, uncaring, and/or antisocial behavior coupled with a complete lack of empathy for others, despite exhibiting outwardly normal behavior.
Past studies have shown that psychopathic offenders are different from regular criminal in a variety of ways. While regular criminals tend to respond to threats swiftly and are often quick-tempered and aggressive, psychopaths have a low response level to threats and a cold or indifferent demeanor, and their aggression tends to be premeditated.
“Evidence is now accumulating to show that both types of offenders present abnormal, but distinctive, brain development from a young age,” explains Dr. Nigel Blackwood, co-author of the study. Understanding these neurological underpinnings of psychopathy may improve interventions during childhood, when psychopathic behavior emerges as something distinct from ordinary delinquency, the scientists said.
Brains of participants with psychopathy characterized by distinct abnormalities
For the study, Dr. Blackwood and his colleagues conducted MRI scans of the brains of 12 violent criminals with psychopathy, 20 violent criminals with antisocial personality disorder but not psychopathy, and 18 healthy people who were not criminals. The criminals had been convicted of murder, rape, attempted murder or grievous bodily harm in the United Kingdom.
While their brains were being scanned, the participants were asked to play a matching game to assess their ability to change their behavior when confronted with rewards and punishment.
In the group of criminals who were psychopathic, the scientists observed lower volumes of gray matter in brain regions involved in empathy, moral reasoning, and the processing of social emotions such as guilt and embarrassment. They also found abnormalities in white matter fibers leading to the prefrontal cortex, in regions involved in learning from reward and punishment. The other violent criminals performed similarly to the people who were not criminals in this test, the researchers found.
For any person, deciding on how to behave involves generating a list of possible actions, weighing the negative and positive consequences of each, and, hopefully, choosing the behavior most likely to lead to a positive outcome, explains Dr. Hodgins.
“Offenders with psychopathy may only consider the possible positive consequences and fail to take account of the likely negative consequences,” Dr. Hodgins said. “Consequently, their behavior often leads to punishment rather than reward as they had expected.”
Therefore, approaches to rehabilitation that are based on treating the behavior problems of psychopaths similarly to those of criminals who are not psychopathic are bound to fail, the researchers said. In the future, these programs must take into account differences in the personality characteristics of offenders if they are to be successful.
Early intervention
The researchers also suggest that focusing on learning-based interventions during childhood, when there still is the potential to alter brain structure and function, may be a promising approach to controlling psychopathic behavior.
Dr. Hodgins said that researchers are “only beginning to learn about the childhood antecedents of the syndrome of psychopathy,” but that her group’s study provides a hypothesis on the emergence of psychopathy and how to test for it in children.
There is ongoing research trying to understand how to help children with psychopathic characteristics — that is, being callous, unemotional and prone to disruptive conduct — to become more emotionally responsive, Dr. Hodgins said. This may include focusing on reward and using negative reinforcement sparingly when interacting with these children.
“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,” Dr. Hodgins said.
But the abnormalities of brain structure and function associated with persistent violent behavior are subtle and complex, the researchers added, and little is known about how the interaction of genes and the environment contributes to the development of these cold, calculated offenders.