Study: Combat stress alters brain activity

Stress from combat changes activity in soldiers' brains, compromising their ability to focus attention, researchers in the Netherlands say.

Dutch veterans who served with NATO in Afghanistan showed declines in their working memory and in the capacity to sustain attention in tests about a month and a half after arriving home, according to a brain imaging study published Monday in the Proceedings of the National Academy of Sciences. The structural changes mostly disappeared a year and a half after the soldiers were removed from active duty, the researchers found.

Studies have shown that chronic stress increases the likelihood of psychiatric illnesses, prompting some nations to boost post-combat evaluations.

President Barack Obama signed an executive order Aug. 31 increasing suicide prevention efforts for U.S. veterans and expanding their access to mental-health care as returning soldiers face an unemployment rate more than 3 percentage points higher than the rest of the population.

"If you have been stressed for a long time, more or less continuously, there are some remnants," said Guido van Wingen, a neuroscientist at the Brain Imaging Center in Amsterdam who helped to write the study.

"But the brain is almost entirely capable of restoring if you give people enough time to go on with their normal lives. This should be optimistic for everyone returning from deployment."

The study examined the differences between 33 healthy Dutch soldiers sent to Afghanistan as part of the NATO and 26 peers who were never deployed. They had matched their nondeployed peers on brain scans and memory tests taken before they left for war.

Magnetic resonance imagining scans of the blood flow in the brains showed those who had been deployed had significantly less activity than the control group in the midbrain, a region important for voluntary movement.