Psychologists at the University of Alabama in Birmingham have been startling people in an attempt to help those with post-traumatic stress disorder (PTSD). They used functional magnetic resonance imaging (fMRI) to measure what went on in people's brains when they heard a loud, unexpected burst of static. When the participants heard the sound there was an increase in activity in the frontal lobes of their brains. The amount of activity in this part of the brain predicted the physiological stress (sweaty palms and racing hearts) experienced by the participants. When the participants expected the sound there was much less activity in this part of the brain. The scientists hope that the discovery of which part of the brain is activated when people are shocked might allow them to develop treatments for PTSD.
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