- Uncertainty affects performance in many cognitive tasks, including the visual-search task, and individual differences in the experience of uncertainty may contribute to several psychological disorders. Despite the importance of uncertainty, to date, no study has explained the basic mechanisms underlying individual differences in the experience of uncertainty. However, it has been suggested that inhibition, a cognitive mechanism aimed at suppressing unwanted thoughts or actions, may affect the development of uncertainty. In the current study, we investigated the relationship between inhibition and behavioral responses to uncertainty in the visual-search task. To accomplish this goal, forty six university students completed a novel combined visual-search and stop-signal task, in which we manipulated the degree to which the inhibitory control system was activated by varying the proportions of stop signals in separate blocks. We utilized target-absent trials in the visual-search task as a behavioral probe of responses to uncertainty. We found that activating higher levels of inhibitory control resulted in faster responses to target-absent visual-search trials, while not affecting target-present trials. These findings suggest that activation of inhibitory control may causally affect behavioral responses to uncertainty. Thus, individual differences in inhibitory control may influence the ability to rely on internal-ambiguous cues which are common in visual-search and other cognitive tasks. Clinical implications for obsessive-compulsive disorder (OCD) and other disorders involving deficient inhibitory control and difficulty with uncertainty are discussed.