A new study published in the journal NeuroImage: Clinical suggests that youths between the ages of 12 and 18 who have committed homicide have significantly different brain structures, compared with other teenage criminals who have not committed homicide.
The research team, including senior study author Dr. Kent Kiehl of The Mind Research Network in Albuquerque, New Mexico, says the findings may lead to new treatments and behavioral therapies to prevent violent crimes.
According to the study background, violence that results in homicide puts severe emotional and financial burden on society. The researchers say that around 15,000 homicides are committed in the US every year, directly affecting 9.3% of Americans. Each homicide offense costs more than $17 million and, in 2011, the total cost of homicides in the US reached $250 billion.
But the team notes that regardless of such figures, there have been no resolute neuroscientific studies looking at youth who commit homicide - a population that the researchers believe may be most at risk for adopting violent behavior.
"Adolescence is a time of signiﬁcant biological, cognitive, and neural changes, and is sometimes associated with reckless, irresponsible, delinquent, and at times, violent behavior," the study authors explain.
"Most adolescents age out of this type of behavior, but a small percentage of youth continue this anti-sociality into adulthood and are referred to as being on the 'life-course persistent' trajectory," the researchers say. "Research that attempts to identify youth at the highest risk of committing serious and violent crimes as adolescents and/or adults could be particularly valuable for prevention and treatment efforts."
Homicide offenders 'had reduced gray matter in their brains'
Using what is described as "high-resolution structural magnetic resonance imaging (MRI) and voxel-based morphometry," the researchers analyzed the brains of 20 male youths who had committed homicide alongside the brains of 135 youth offenders who had not committed homicide. All juveniles were incarcerated in maximum-security facilities.
The MRI scans were also compared with the brain scans of two control groups that consisted of individuals who had not committed any criminal offenses, in order to help validate results.
The researchers found that the youth offenders who committed homicide had lower total brain volumes than those who had not committed homicide.
In particular, they had reduced volumes of gray matter in the medial and lateral temporal lobes, including the hippocampus and posterior insula. The temporal lobes, the researchers say, are involved in processing emotion and controlling impulsive behavior.
According to the team, the technology used in the study was able to determine which brains belonged to homicide offenders with 81% accuracy, indicating that such methods could be used to identify individuals who are at risk of committing serious crimes.
Commenting on the findings, Dr. Kiehl says:
"As policymakers grapple with the high societal, human, and budgetary costs of violent crime and incarceration among young people, it is within the power of neuroscience to help understand the brain abnormalities involved.
Then we can create medicine and behavioral therapies to reduce the likelihood of these violent crimes, or in a perfect world, prevent these crimes from happening at all. It is my hope that these findings will lead to the ability to better understand at-risk kids before they commit homicide and put them on a different and productive path."
Last year, Medical News Today reported on a study by UK researchers, which suggested that, as a result of modern-day high-resolution digital images, corneal reflections in photographs could be used to solve crimes.