Imperative and Interrogative motivations shape decision-making and long-term memory via distinct neural routes

Poster Session B - Sunday, April 14, 2024, 8:00 – 10:00 am EDT, Sheraton Hall ABC

Yuxi Candice Wang¹ (yuxi.wang@duke.edu), Alyssa H. Sinclair², R. Alison Adcock¹; ¹Duke University, ²University of Pennsylvania

Motivation influences decision-making and memory. Imperative motivation is performance-oriented and urgency-focused, leading to sparse, decontextualized memory. In contrast, interrogative motivation is learning-oriented and supports both present and future goals, which encourages exploration and enhances memory for details. We used fMRI (N=59) to investigate the underlying neural mechanisms for imperative and interrogative motivations. Participants were randomly assigned to imperative or interrogative motivation group, where they imagined executing or planning a museum heist. Next, all participants completed the same reinforcement learning task where they repeatedly chose among four doors (choice phase) to reveal a trial-unique painting along with its reward value (feedback phase). Cumulative rewards earned were converted to monetary bonus to be paid on the next day, after a surprise memory test for paintings. Replicating our prior behavioral findings, participants in the imperative group made more optimal choices during reinforcement learning while participants in the interrogative group showed better incidental memory for paintings. Model-based analyses found more exploitation for the imperative group, and more directed exploration to resolve uncertainty for the interrogative group. fMRI results during the choice phase showed, for the imperative group, dorsal striatal activation predicting exploitation and, for the interrogative group, greater representation of uncertainty in the vmPFC. During the feedback phase, reward representation in the VTA was stronger in the interrogative group than in the imperative group, for whom amygdala activation predicted memory success. In sum, we show that motivational states shift the balance between exploitation and exploration during decision-making and pave distinct routes to long-term memory.

Topic Area: LONG-TERM MEMORY: Episodic