Schedule of Events | Search Abstracts | Invited Symposia | Symposia | Rising Stars | Poster Sessions | Data Blitz

A dominant exploration-exploitation axis shapes individual differences in sequential decision-making

Poster Session A - Saturday, March 7, 2026, 3:00 – 5:00 pm PST, Fairview/Kitsilano Ballrooms

Mojtaba Abbaszadeh¹ (mojtaba.abbaszadeh@umontreal.ca), Erica Ozanick¹, Noa Magen¹, David Darrow², Xinyuan Yan², Nicola Grissom², Alexander Herman², Becket R. Ebitz¹; ¹University of Montreal, ²University of Minnesota

People vary widely in how they make decisions under uncertainty. Although many studies use this variability to estimate differences in specific cognitive parameters, the core dimension(s) that organize individual differences in uncertain decision-making remain unclear. Here, we analyzed behavioral data from 1001 participants performing a restless three-armed bandit task in which reward probabilities changed unpredictably over time. Using a novel analytical approach that accounts for the intrinsic stochasticity of this task, we identified a dominant, nonlinear axis of individual variability. This principal axis was strongly and selectively associated with the probability of exploration, as estimated by a latent-state model. Thus, the main driver of individual differences in bandit task performance appears to be the tendency to explore versus exploit, rather than personality traits, reinforcement-learning model parameters, or simple low-level strategies. Demographic factors also predicted position along this axis: participants at the exploratory end tended to be younger, and self-identified men were overrepresented at both extremes. Together, these findings provide a principled framework for characterizing individual differences in task behavior and highlight the cognitive and demographic factors that shape decision-making under uncertainty.

Topic Area: THINKING: Decision making