Trauma Can Affect Brain Function In Healthy People Several Years After Event
Exposure to trauma may create enough changes in the brain to sensitize people to overreact to an innocuous facial gesture years later, even in people who don't have a stress-related disorder.
It appears that proximity to high-intensity traumas can have long lasting effects on the brain and behavior of healthy people without causing a current clinical disorder. But these subtle changes could increase susceptibility to mental health problems later on. These findings are reported in the May issue of Emotion, published by the American Psychological Association (APA).
Evidence that trauma can have long-term effects on the brains of healthy individuals was demonstrated by measuring adults' reactions to emotional stimuli several years after witnessing a trauma, said lead author Barbara Ganzel, PhD, and colleagues. In the experiment, 22 healthy adults viewed fearful and calm faces while undergoing functional magnetic resonance imaging (fMRI) to measure their bilateral amygdala activity (part of the brain that judges emotional intensity, and that forms and stores emotional memories) between 3.5 and 4 years after September 11, 2001.