A survey of 197 youth offenders in England — boys aged 11 to 19 who have been incarcerated — found that they are three times more likely to have had a traumatic brain injury (TBI) than their non-offending counterparts. About half of the 197 youths reported a brain injury, in keeping with another English survey of adult prisoners that found a rate of TBI of 60%.
Traumatic brain injury has long been associated with adult prisoners: the Centers for Disease Control and Prevention (CDC) found that between 25% and 87% of men and women imprisoned for violent crimes have suffered a TBI prior to incarceration. That’s a big range, but even at its low end, it is about three times higher than the rate of TBI in the general population (8.5%). (More on Time.com: Amnesia and a Camera: Photos as Memories)
The new British study also found that youth offenders with multiple brain injuries were more likely to have carried out more violent crimes. The researchers said that while brain injury alone was unlikely to have spurred criminal behavior, it appeared to play a role in children who were already at risk of committing crimes.
“The associations between brain injuries and crime are very problematic,” Huw Williams, the study’s author and an associate professor of clinical neuropsychology at the University of Exeter, told BBC Radio 4′s All in the Mind. “It may not be causal in the sense of increasing the chances of crime, but it may well be a factor in terms of re-offending.” (More on Time.com: Special Report: Kids and Mental Health)
People who have suffered a TBI have trouble remembering regimented rules, keeping anger in check, planning and communicating, according to the CDC. These memory and behavior problems make ordinary life hard enough, but they can make survival difficult in a prison setting, and may contribute to rates of re-offense.
The survey found that a third of the young offenders had been “knocked out” more than once; boys who suffered three or more TBIs were more likely to have committed more violent crimes. Whether the repeated brain injury is a result of running with a tough crowd and getting into fights, or whether brain injury causes impulse problems that cause delinquent behavior is unclear. (More on Time.com: Study: Playing Tetris to Prevent PTSD Flashbacks)
“It might be a marker that these people are having much more violent lives, and the head injuries are a consequence of that, but it may also be likely that they are starting to have increased problems in terms of the neurocognitive effect of a brain injury,” Williams told the BBC.
Williams and the CDC recommend increasing screening for head injury. Williams suggests that police could ask the simple question during arrest — “Have you ever been knocked unconscious?” — and that follow-up treatment could be provided for those with cognitive disabilities as a result of their head trauma. The CDC is currently studying the most effective methods of care for prisoners with TBI.
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