NEW YORK (AP) — About half of all 16- to 18-year-olds coming into New York City's jails say they had a traumatic brain injury before being incarcerated, most caused by assaults, according to a new study that's the latest in a growing body of research documenting head trauma among young offenders. Experts say the findings, published this week in The Journal of Adolescent Health, could lead to better training for correction officers on how to deal with the possible symptoms of such trauma, which include problems with impulse control and decision-making. A growing body of research shows that inmates whose brains have been jolted by trauma are linked to higher rates of breaking jailhouse rules, substance abuse and greater difficulty re-entering society after detention, said John D.