Dec 12, 2013 09:37 AM EST By Staff Reporter, UniversityHerald Reporter

Long-time exposure to media coverage on distressing and catastrophic events can affect mental health, according to a University of California, Irvine study. Researchers said that those who spent six or more hours a day watching terrorism events on TV showed higher levels of acute stress symptoms.

This finding is prominent in people who have previously experienced a traumatic event, those who are used to watching traumatic events and in people with a pre-existing mental health condition.

"We were very surprised that repeated media exposure was so strongly associated with acute stress symptoms," E. Alison Holman, associate professor of nursing science at UC Irvine and the study's lead author, said in a statement."We suspect that there's something about repeated exposure to violent images or sounds that keeps traumatic events alive and can prolong the stress response in vulnerable people."

 "There is mounting evidence that live and video images of traumatic events can trigger flashbacks and encourage fear conditioning. If repeatedly viewing traumatic images reactivates fear or threat responses in the brain and promotes rumination, there could be serious health consequences."

For the study, researchers asked more than 4,500 adults to participate in surveys, two to four weeks after the 2013 Boston Marathon bombings, to determine the acute stress people experienced through direct/indirect exposure (media) to the tragic incident. The media included in the study was television, social media, and radio, videos, print and audio.

The researchers found that those who spent watching six or more hours a day of news coverage on the bombing were nine times more likely to report high acute stress symptoms such as hyper vigilance, disturbing thoughts and feelings of emotional detachment when compared to people who watched it less than an hour every day or those who were actually present at the marathon.

The findings have been published in the journal Proceedings of the National Academy of Sciences.

Previous studies have already established that people experience stress when they watch media coverage of traumatic events for more time.

-          The National Center for PTSD have found  that people who watched more news coverage of 9/11 terrorist attacks experienced more stress symptoms than those who comparatively spent less time watching the TV coverage.

-          Children, who spent more time watching Oklahoma City bombing experienced more symptoms similar to PTSD.

However, a Tel Aviv University study is contradicting both the findings. It said that frequent exposure to negative information (news of catastrophes and crime) makes a person immune to sadness.

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