Brain Scan (IMAGE) University of Washington Caption Amygdala activation (shown in red) in the left hemisphere of the brain was associated with PTSD symptoms following the Boston Marathon bombing. Credit Katie McLaughlin, University of Washington Usage Restrictions with credit License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.