Neural substrates of choosing actions and motivational drive, a role for the striatum

Alice Yiqing Wang

Optimal decision making requires one to determine the best action among available alternatives as well as the most appropriate level of engagement for performance. While current research and models of decision making have largely focused on the former problem, or action selection, less is known about the latter problem of the selection of motivational drive. Thus, I designed a self-paced decision-making paradigm that aimed to dissociate both facets of selection in rats. First, I showed that the expected net value of potential options influenced rats' general motivation to perform: rats globally exhibited shorter latency to initiate trials in states of high net return than in states of low net return. In contrast, the relative value of options biased choice direction. To study the neural substrates underlying either process, I examined the role of the striatum, which is closely...