School Bullies More Likely to Commit Partner Violence
And, violent behavior linked to increased gray matter volume in the mesolimbic reward system
TUESDAY, June 7 (HealthDay News) -- Boys who bullied their peers as a child are more likely to commit intimate partner violence (IPV) as adults; and, men who are violent have increased gray matter (GM) volume in their mesolimbic reward systems, according to two studies published online June 6 in the Archives of Pediatrics & Adolescent Medicine and the Archives of General Psychiatry, respectively.
Kathryn L. Falb, M.H.S., from the Harvard School of Public Health in Boston, and colleagues investigated the relationship between bullying peers as a child and committing physical or sexual IPV as an adult in a sample of 1,491 men, aged 18 to 35 years. IPV during the previous year was the main outcome studied. Compared to men who did not bully their peers in school, those who rarely bullied were 1.53 times more likely to commit IPV in the previous year, and those who frequently bullied their peers were 3.82 times more likely to commit IPV.
Boris Schiffer, Ph.D., from the University of Duisburg-Essen in Germany, and colleagues investigated the alterations in GM volume associated with violent behavior and lifelong substance use disorders. Compared to nonoffenders, violent offenders had increased GM volume in the amygdala bilaterally, the left nucleus accumbens, and right caudate head, and reduced GM volume in the left insula. These changes in volume were associated with psychopathy scores and lifelong aggressive behavior scores.
"A greater GM volume in the mesolimbic reward system may be associated with violent behavior," Schiffer and colleagues write.