Intolerance of uncertainty and insula activation during uncertain reward.

Individuals with high intolerance of uncertainty (IU) have been shown to exhibit abnormal threat responding, which may be mediated by hyperactive anterior insula (aINS) response to uncertainty. Research has indicated that individuals with high IU also exhibit abnormal positive valence responding, suggesting that IU may impact responding to uncertainty regardless of the valence of the potential outcome. To date, no study has investigated the neural processes associated with IU and response to uncertain positive stimuli, such as rewards. Therefore, this study was designed to examine the association between individual differences in IU and neural activation during uncertain reward using functional magnetic resonance imaging (fMRI). Thirty-seven adults completed a self-report measure of IU and a reward task during fMRI. Consistent with the threat literature, greater IU was associated with increased aINS activation during uncertain reward. This association was more robust for the prospective IU subscale, a dimension characterized by worry about future events. Together with prior studies, these findings provide evidence that IU is related to abnormal threat and reward responding, and that these deficits may be similarly linked to hyperactive aINS response to uncertainty.