Girls who are at a higher risk of depression might have brains that deal differently with punishment and rewards. Researchers from Stanford University studied 26 girls between the ages of 10 and 14. Half of them had mothers with recurrent depression and were considered to be at high-risk themselves while half had no personal or family history of depression. Both groups were given MRI brain scans while completing a task that could result in either reward or punishment. Girls in the high risk group had a weaker brain response to the anticipation and receiving of a reward. In particular they showed no activitiy in a part of the brain called the dorsal anterior cingulate cortex which is believed to play a role in linking learning to reward. However, the girls in the at-risk group showed greater brain activity than the other girls in response to being punished.
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