Distinct roles of striatal direct and indirect pathways in value-based decision making

• Main Authors: Shinae Kwak, Min Whan Jung
• Format: Article
• Language: English
• Published: eLife Sciences Publications Ltd 2019-07-01
• Series: eLife
• Subjects: basal ganglia; D1 receptor; D2 receptor; reversal; dynamic foraging; reinforcement learning
• Online Access: https://elifesciences.org/articles/46050

The striatum is critically involved in value-based decision making. However, it is unclear how striatal direct and indirect pathways work together to make optimal choices in a dynamic and uncertain environment. Here, we examined the effects of selectively inactivating D1 receptor (D1R)- or D2 receptor (D2R)-expressing dorsal striatal neurons (corresponding to direct- and indirect-pathway neurons, respectively) on mouse choice behavior in a reversal task with progressively increasing reversal frequency and a dynamic two-armed bandit task. Inactivation of either D1R- or D2R-expressing striatal neurons impaired performance in both tasks, but the pattern of altered choice behavior differed between the two animal groups. A reinforcement learning model-based analysis indicated that inactivation of D1R- and D2R-expressing striatal neurons selectively impairs value-dependent action selection and value learning, respectively. Our results suggest differential contributions of striatal direct and indirect pathways to two distinct steps in value-based decision making.