FC29-01 - Reduced cortical inhibition in violent offenders: A study with transcranial magnetic stimulation

Abstract

IntroductionAggression and violent behaviour are often noticed as a threat of society. Therefore, the understanding of violent behaviour has high social relevance.ObjectivesThe investigation sample comprised 80 right-handers: 40 prisoners who committed severe violent crimes and 40 controls with no history of violence. All subjects were male and matched for age.AimesWe performed a study with transcranial magnetic stimulation (TMS) in a sample of violent offenders in order to measure cortical inhibition in the motoneural system which is part of the frontal cortex.MethodsTo investigate the intracortical inhibition and the intracortical facilitation we conducted paired-pulse stimulation according to the technique of Kujirai et al. (1993). The investigation sample comprised 80 right-handers: 40 prisoners who committed severe violent crimes and 40 controls with no history of violence. All subjects were male and matched for age.ResultsUsing the paired-pulse paradigm with interstimulus intervals (ISI) of 1–15 ms, a reduced cortical inhibition (ISI 3 ms) was found in violent offenders compared with control subjects in the left cortex.ConclusionsThese findings corroborate the hypothesis of inhibition deficits in violent offenders when compared with control subjects due to a lack of impulsive control.