Neural Dynamics Underlying Uncertain Reward Evaluation in Individuals With Intolerance of Uncertainty

Intolerance of uncertainty (IU) has long been recognized as a transdiagnostic factor for various internalizing disorders. Previous studies have examined the influence of IU on the processing of uncertain threats, but little attention has been paid to uncertain reward processing. The current event-related potential study investigated this issue by examining the effects of IU on the neural dynamics underlying reward evaluation in different uncertain scenarios. We recorded EEG activity from a high-IU group (N = 35) and a low-IU group (N = 36) when they completed three guessing tasks in which rewards were delivered with either predictable or unpredictable probability, time, or magnitude. Behaviorally, the high-IU relative to the low-IU group exhibited a general aversion to uncertainty. During the early stage of reward evaluation as indexed by the reward positivity, participants with low IU, instead of those with high IU, were sensitive to predictable versus unpredictable rewards, specifically for the time task. During the late stage as indexed by the P3, the high-IU versus low-IU group was more sensitive to predictable versus unpredictable conditions, regardless of uncertainty type. Our findings demonstrate IU-related individual variability in neural dynamics underlying uncertain feedback processing in the reward domain, supporting a valence-independent maladaptation in uncertainty processing in IU.