Brain Glitch May Raise Some Girls' Odds of Depression

Young girls at high risk for depression appear to have a malfunctioning reward system in their brains, a new study suggests.

The finding comes from research that included a high-risk group of 13 girls, aged 10 to 14, who were not depressed but had mothers who experienced recurrent depression and a low-risk group of 13 girls with 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.

Compared with girls in the low-risk group, those in the high-risk group had weaker neural responses during both anticipation and receipt of the reward. Specifically, the high-risk girls showed no activation in an area of the brain called the dorsal anterior cingulate cortex, believed to play a role in reinforcing past experiences to assist learning.

The high-risk girls did have greater activation of this brain area when receiving punishment, compared with the other girls. The researchers said that this suggests that high-risk girls have an easier time processing information about loss and punishment than information about reward and pleasure.

Considered together with reduced activation in the striatal areas commonly observed during reward, it seems that the reward-processing system is critically impaired in daughters who are at elevated risk for depression, although they have not yet experienced a depressive episode, wrote Ian H. Gotlib, of Stanford University, and his colleagues.

Clearly, longitudinal studies are needed to determine whether the anomalous activations observed in this study during the processing of rewards and losses are associated with the subsequent onset of depression, they concluded.

The study was published in the April issue of the Archives of General Psychiatry.

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