Psychopathic violent offenders have abnormalities in brain regions that may prevent them from learning from punishment, a finding that may have implications for prevention and treatment, according to a novel imaging study.
"One in five violent offenders is a psychopath. 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," Sheilagh Hodgins, of the University of Montreal and Institut universitaire en santé mentale de Montréal, who worked on the study, said in a statement.
"Psychopathic offenders are different from regular criminals in many ways. Evidence is now accumulating to show that both types of offenders present abnormal, but distinctive, brain development from a young age," said study investigator Nigel Blackwood, MD, forensic psychiatrist from King's College London, United Kingdom.
The study was published January 29 in the Lancet Psychiatry.
Distinct Neural Dysfunction
Identifying neural mechanisms of persistent, psychopathic, violent behavior is important for developing programs to prevent violent crime and effective rehabilitation programs.
To that end, the investigators used fMRI to study 12 violent offenders with antisocial personality disorder and psychopathy, 20 violent offenders with antisocial personality disorder but not psychopathy, and 18 healthy nonoffenders. The offenders (all men) had been convicted of murder, rape, attempted murder, and grevious bodily harm and were recruited from Britain's probation service.
The researchers report finding "distinctive neural dysfunctions" in violent offenders with antisocial personality disorder and psychopathy related to "severe impairment in learning from punishment."
Among the offenders with psychopathy, they saw reductions in gray matter volume bilaterally in the anterior rostral prefrontal cortex and temporal poles. These regions are involved in empathy, the processing of prosocial emotions, such as guilt and embarrassment, and moral reasoning.
They also found abnormalities in white matter fiber tracts in the dorsal cingulum, linking the posterior cingulate cortex to the medial prefrontal cortex associated with a lack of empathy that is typical of psychopathy. These regions are involved in learning from rewards and punishment.
During fMRI, the violent offenders and nonoffenders completed a neuropsychological task that gauged their ability to adjust their behavior when the consequences of their responses changed from reward to punishment.
Again, the researchers found that violent offenders with psychopathy showed abnormal responses in key brain regions relative to the other two groups. 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," Dr Blackwood explained in the statement.
"Punishment signals the necessity to change behavior. Clearly, in certain situations, offenders have difficulty learning from punishment to change their behavior," Hodgins added.
"The results of our studies are providing insights into the neural mechanisms characterizing adult violent offenders that may be used, along with other findings, in designing programs to reduce recidivism. Our results also provide hypotheses about the abnormal development of violent offenders to be tested in studies of children," Dr Blackwood said.
This information is critical to the development of programs to prevent violent criminality. "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," Hodgins said.
Crossing Boundaries
In an accompanying comment, Inti A. Brazil, of Donders Institute for Brain, Cognition and Behavior, Radboud University, Nijmegen, the Netherlands, notes that "neural plasticity is high in the developing brain and, therefore, genetic, epigenetic, and environmental factors can shift brain organization towards a different homeostatic balance in children with callous-unemotional traits compared with those without these traits to manage behavior in daily life."
"From this perspective, the different patterns of activations observed in the violent offenders with antisocial personality disorder with and without psychopathy and healthy individuals might reflect these diverging neurodevelopmental pathways to cope with events signaling the need to adapt," Brazil writes.
This study provides "intriguing new insights [which] lend themselves to reflecting about the complexity of antisocial personality disorder and psychopathy and, even more complex, their relations with neurocognitive functioning and behavior," Brazil concludes.
In a podcast, Niall Boyce, MD, PhD, editor of the Lancet Psychiatry, noted that psychopathic personality disorder is a subject that "crosses the boundaries of the health system and the criminal justice system. It's much misunderstood, and though it's been recognized and described in various forms over many years, it's only with the rise of modern experimental methods that we are beginning to understand it."
The authors report no relevant financial relationships.
Lancet Psychiatry. Published online January 29, 2015. Abstract, Editorial
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Cite this: New Insight Into the Psychopathic Brain - Medscape - Feb 05, 2015.
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