Abstract
Adaptive decisions are not instantaneous choices but processes that unfold over time, requiring organisms to decide not only what to choose but how long to persist in that choice as opportunity costs mount. Prevailing theories in neuroeconomics and reinforcement learning model value as a static quantity computed at the moment of choice, leaving persistence under specified. This thesis examines an alternative view in which valuation unfolds dynamically, with decision relevant signals changing across distinct stages of a decision. To test this, I developed the TIME Bandit task, a self paced foraging paradigm that dissociates strategy, choice, and persistence in rats. Behaviorally, this design revealed that while standard reinforcement learning models accounted for which option rats chose, they did not fully explain how long rats waited, indicating that persistence reflects a distinct post choice evaluation. Using fiber photometry, I found that nucleus accumbens dopamine release varies systematically across decision stages. Pre choice dopamine was associated with strategic state (explore vs. exploit); choice evoked activity predicted subsequent waiting time; and during waiting, dopamine declined toward a threshold that coincided with quitting on single trials. A normative decay to threshold model provided a compact description of these behavioral and neural dynamics. Together, these findings suggest that valuation is distributed across time rather than confined to a single computation at choice. They further indicate that mesolimbic dopamine signals differ across decision epochs, relating to strategy, commitment, and persistence in ways not captured by a unitary value signal. This work offers an integrated framework for interpreting dopamine dynamics during extended decisions and highlights the importance of time investment as a behavioral window into post choice valuation.
Committee Chair
Adam Kepecs
Committee Members
Camillo Padoa-Schioppa; Larry Snyder; Marco Pignatelli; Yao Chen
Degree
Doctor of Philosophy (PhD)
Author's Department
Biology & Biomedical Sciences (Neurosciences)
Document Type
Dissertation
Date of Award
4-28-2026
Language
English (en)
DOI
https://doi.org/10.7936/80ty-jp37
Recommended Citation
Arora, Apoorva, "Valuation in Time: Mesolimbic Dopamine tracks Decision Strategy, Commitment and Persistence" (2026). Arts & Sciences Graduate Student Theses and Dissertations. 3753.
The definitive version is available at https://doi.org/10.7936/80ty-jp37