Brain activity analyzed with functional MRI (fMRI) has shown convicted criminals with relatively low anterior cingulate activity were twice as likely to be rearrested as offenders with high activity in this region, according to research published online March 27 in Proceedings of the National Academy of Sciences .
“These results suggest a potential neurocognitive biomarker for persistent antisocial behavior,” wrote Kent A. Kiehl, PhD, associate professor of psychology at the University of New Mexico and director of mobile imaging at the Mind Research Network in Albuquerque, N.M., and colleagues.
The anterior cingulate cortex is a limbic region associated with error processing, conflict monitoring, response selection and avoidance learning, explained the authors. Damage to the region has been shown to produce changes in disinhibition, apathy and aggressiveness.
Previous research has focused on risk factors such as age, criminal history, impulsivity and drug use as predictors of antisocial behavior. Impulsivity, or behavioral disinhibition, is one of the most widely studied factors, with personality tests and neuropsychological measures used to assess the trait. The authors noted, however, these measures are only proxies for direct measurement of the brain’s inhibitory and cognitive control systems.
For a more direct evaluation of these systems, Kiehl and colleagues conducted a study involving 96 male criminal offenders ages 20-52. Participants were scanned on a mobile MRI while they performed a go/no go impulse-control task, and the population was followed for up to four years after their release from prison to track recidivism.
Results showed that people with lower activity in the anterior cingulate cortices had double the odds of reoffending. “This pattern of results raises the possibility that brain activity in regions such as the [anterior cingulate cortex], elicited by a simple experimental task, may lend incremental utility to existing behavioral risk factors in the ability to predict rearrest,” wrote the authors.
Kiehl and colleagues were skeptical that biomarkers like the one they identified could independently replace currently used risk assessments or psychological measures, but they could improve risk estimates when used in combination with these other evaluations.
The authors were particularly concerned with the notion that neurobiological markers could be used to make predictions about individual offenders’ risk of reoffending, noting these estimates must meet sensitivity and specificity thresholds in large random samples, must survive required legal standard of proof and must be determined not to violate offender rights.
“If so, their potential admissibility in legal settings may be greatest in decisions involving a low standard of proof such as treatment access decisions rather than in high-stakes decisions such as sentencing,” they wrote.
The findings also reveal the potential of targeted treatments aimed at increasing cognitive control systems to reduce future recidivism, according to Kiehl and colleagues.