Perceiving Shell Shock

Soldiers' brains adapt to perceived threats during deployment

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) According to researchers at the Military Mental Health Research Center and the Rudolf Magnus Institute of Neuroscience, soldiers' brains adapt to perceived threats rather than actual events during a mission.

In other words, stress is caused by what the individual views as a threat, not necessarily by the actual threat that exists. This perceived threat is responsible for neural changes.

Combat-induced stress is known to cause complications such as fatigue, slower reaction times, disconnection from one's surroundings, and difficulty prioritizing.

In a study of 36 soldiers deployed in Afghanistan between 2008 and 2010, researchers found that continual exposure to stress leads to changes in the neural circuits of the brain that control fear and vigilance. The study is the first of its kind to have a control group comparison.

Soldiers underwent two brain scans in addition to filling out a questionnaire about their combat experiences. Researchers found increased activity in the amygdala and insole, the parts of brain that control fear and vigilance. Changes to the frontal lobe (the emotional center of the brain) depended on how soldiers perceived events during deployment. Although the soldiers did not develop post-traumatic stress disorder (PTSD), the changes to their brains led to similar symptoms that lasted for at least two months after soldiers returned home.

Future studies will focus on how long these changes last in soldiers' heads, and if perceived high levels of stress put soldiers at an increased risk of developing symptoms of post-traumatic stress.

The study is published in the journal Molecular Psychiatry.

Reviewed by: 
Review Date: 
January 25, 2011
Last Updated:
January 26, 2011