Kent A. Kiehl

Is there something in the physical brain that triggers or allows impulsivecriminal behavior?  That's an idea psychologists have debated for decades, but it is only within the last few years that researchers have had an opportunity to look for clues.  The opportunity has come in the form of a portable functional magnetic resonance machine, which UNM Psychology Associate Professor and Director of Mobile Imaging at the nonprofit Mind Research Network Kent A. Kiehl has used at several corrections facilities in New Mexico.

Kiehl and his colleagues at Washington University in St. Louis, the Oregon Health and Science University in Portland, Oregon, and the Mind Research Network in Albuquerque have closely examined the brains of 107 incarcerated adolescents, searching for a possible connection between severe impulsivity and criminal behavior.  In a paper published in the Proceedings of the National Academy of Sciences (PNAS) this summer titled "Premotor functional connectivity predicts impulsivity in juvenile offenders" they explore impulse behavior in teenagers.

The researchers were looking for connections between activity in various areas of the brain and impulsive behavior.  The research involved examining the brains of juveniles incarcerated in a high security facility using functional magnetic resonance imaging.  These scans were compared with a control group of individuals over a span of ages from 13 to 55. The scans were performed while individuals were in a resting state.

The researchers report that "In less-impulsive juveniles and normal controls, motor planning regions were correlated with brain networks associated with spatial attention and executive control.  In more-impulsive juveniles, these same regions correlated with the default-mode network, a constellation of brain areas associated with spontaneous, unconstrained, self-referential cognition."

The strength of the information allowed them to predict impulsivity scores for individuals.  They concluded that "the change in functional connectivity with age mirrored that of impulsivity; younger subjects tended to exhibit functional connectivity similar to the more impulsive incarcerated juveniles, whereas older subjects exhibited a less-impulsive pattern. "  They said," this observation suggests that impulsivity in the offender population is a consequence of a delay in typical development, rather than a distinct abnormality."

Kiehl says very impulsive adolescents typically failed to plan ahead or to envision the consequences of their actions.  He says if researchers can measure which individuals are most likely to be impulsive, then it may be possible to tailor treatment for them so they have a greater awareness of the consequences of their actions, which in turn may make them less likely to reoffend.

Kiehl also noted that the delays in brain development they observed in impulsive youth, effects perhaps due to psychological trauma or other environmental experiences, has critical importance for how juveniles are treated by the criminal justice system.  Indeed, in the next steps of his research Kiehl and his team are documenting how delayed brain maturation in youth can change over time with effective treatment – results that are sure to make a call for more evidence-based treatment of impulsive youth involved in the criminal justice system.

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