University of Pennsylvania researchers found that rodents that had been exposed to stress had a weakened alcohol-induced dopamine response and voluntarily drank more alcohol compared to controls due to changes in the circuitry in the ventral tegmental area, the heart of the brain's reward system.

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University of Pennsylvania researchers found that rodents that had been exposed to stress had a weakened alcohol-induced dopamine response and voluntarily drank more alcohol compared to controls due to changes in the circuitry in the ventral tegmental area, the heart of the brain's reward system.