Rostrolateral prefrontal cortex and individual differences in uncertainty-driven exploration.
How do individuals decide to act based on a rewarding status quo versus an unexplored choice that might yield a better outcome? Recent evidence suggests that individuals may strategically explore as a function of the relative uncertainty about the expected value of options. However, the neural mechanisms supporting uncertainty-driven exploration remain underspecified. The present fMRI study scanned a reinforcement learning task in which participants stop a rotating clock hand in order to win points. Reward schedules were such that expected value could increase, decrease, or remain constant with respect to time. We fit several mathematical models to subject behavior to generate trial-by-trial estimates of exploration as a function of relative uncertainty. These estimates were used to analyze our fMRI data. Results indicate that rostrolateral prefrontal cortex tracks trial-by-trial changes in relative uncertainty, and this pattern distinguished individuals who rely on relative uncertainty for their exploratory decisions versus those who do not.
Department of Cognitive, Linguistic, and Psychological Sciences, Brown Institute for Brain Sciences, Brown University, Providence, RI 02912-1978, USA. david_badre@brown.edu
David
D
Badre
Bradley B
BB
Doll
Nicole M
NM
Long
Michael J
MJ
Frank
D000293:Adolescent; D000328:Adult; D001931:Brain Mapping; D002755:Choice Behavior; D003198:Computer Simulation; D005106:Exploratory Behavior / Q000502:physiology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007206:Individuality; D008279:Magnetic Resonance Imaging; D008297:Male; D008959:Models, Neurological; D009483:Neuropsychological Tests; D010100:Oxygen / Q000097:blood; D017397:Prefrontal Cortex / Q000098:blood supply / Q000502:physiology*; D011930:Reaction Time; D012054:Reinforcement, Psychology; D035501:Uncertainty; D055815:Young Adult
D010100:Oxygen