Watching Violent TV Shows Linked to Impaired Executive Function in the Human Brain

Violent video games and television have long concerned parents and researchers. Could watching violent scenes impact the human brain? It turns out that that might actually be the case. Scientists have found that young adult men who watched more violence on television had less mature brain development and poorer executive functioning.

The researchers examined young men who provided estimates of their television viewing over the past year, and then kept a detailed diary of their TV viewing for a week. The participants also completed a series of psychological tests measuring inhibitory control, attention and memory. The scientists also employed MRI scans to measure brain structure.

"We found that the more violent TV viewing a participant reported, the worse they performed on tasks of attention and cognitive control," said Tom Hummer, one of the researchers, in a news release. "On the other hand, the overall amount of TV watched was not related to performance on any executive function tests. The worry is that more impulsivity does not mix well with the behaviors modeled in violent programming."

What was more interesting what the MRI showed. It turns out that men with higher violent television exposure had less volume of white matter connecting the frontal and parietal lobes, which can be a sign of less maturity in brain development. In fact, white matter is tissue in the brain that insulates nerve fibers connect different brain regions, making them more efficient. The fact that there was less reveals that executive functioning may have been slightly impaired.

That said, the scientists caution about leaping to conclusions. They're still not sure about a few important facts.

"With this study we could not isolate whether people with poor executive function are drawn to programs with more violence or if the content of the TV viewing is responsible for affecting the brain's development over a period of time," said Hummer in a news release. "Additional longitudinal work is necessary to resolve whether individuals with poor executive function and slower white matter growth are drawn to violent programming or if exposure to media violence modifies development of cognitive control."

The findings are published in the journal Brain and Cognition.