The influence of uncertainty and intolerance of uncertainty on anxiety

Background and objectives: Although the influence of uncertainty and intolerance of uncertainty (IU) on anxiety pathologies has been well-established, only a few studies examined the interaction between uncertainty and IU in producing anxiety. Meanwhile, there is a lack of research utilizing experimental methods to manipulate the situational uncertainty. Therefore, the current study aimed to more systematically investigate whether and how trait IU interacted with uncertainty in the production of anxiety. Methods: the current study examined the influence of threat-related uncertainty and IU on anxiety in a lab setting. A variant of the threat-of-shock paradigm was employed to manipulate the uncertainty level. State anxiety and worry were measured immediately before and after this manipulation. Hierarchical linear modeling was used for data analysis. Results: Results showed that trait IU contributed to elevated state anxiety and worry. Meanwhile, when under imminent threat, uncertainty provoked increased worry but exerted limited influence on state anxiety. The interaction effect of uncertainty and IU on anxiety was not evident in this study. Limitations: Results were based on a non-clinical sample rather than individuals with clinical diagnoses. Conclusions: Uncertainty could be regarded as a trigger of worrying thoughts, while IU is an important cognitive vulnerability factor of anxiety and related symptoms. The possible reasons for these findings and their implications were discussed in light of theoretical models of anxiety, worry, and IU.