Dopamine Depressive Symptoms and Decision-Making: The Relationship between Spontaneous Eyeblink Rate and Depressive Symptoms Predicts Iowa Gambling Task Performance

摘要

Depressive symptomatology has been associated with alterations in decision-making, although conclusions have been mixed with depressed individuals showing impairments in some contexts, but advantages in others. The dopaminergic system may link depressive symptoms with decision-making performance. We assessed the role of striatal dopamine D2 receptor density, using spontaneous eyeblink rate, in moderating the relationship between depressive symptoms and decision-making performance in a large undergraduate sample that had not been screened for mental illness (N=104). Regression results revealed that eyeblink rate moderated the relationship between depressive symptoms and advantageous decisions on the IGT in which individuals with more depressive symptomatology and high blink rates (higher striatal dopamine D2 receptor density) performed better on the task. Computational modeling results demonstrated that depressive symptoms alone were associated with enhanced loss aversive behavior, while individuals with high blink rates and elevated depressive symptoms tended to persevere in selecting options that led to net gains (avoiding options with net losses). These findings suggest that variation in striatal dopamine D2 receptor availability in individuals with depressive symptoms may contribute to differences in decision-making behavior.