Abstract/Summary

Anxiety disorders are the most common mental health issues experienced in society, and can occur earlier in the lifespan than other mental health disorders. Untreated anxiety in young people can lead to challenges at school and home, and can increase the probability of long-term mental health problems. Intolerance of Uncertainty (IU) has been linked to higher levels of anxiety and worry in both adults and children but a number of limitations exist. There is limited research examining IU and worry in young children, a lack of longitudinal research examining associations between IU and worry across childhood, and almost no understanding of how high IU relates to behavioural, cognitive and emotional responses under uncertainty, particularly in children. In Study 1, IU and generalised anxiety were assessed across childhood. The results revealed associations between generalised anxiety and IU at each time point; those with higher IU had higher symptoms than those with lower IU. Contrary to expectations, longitudinal analysis showed that higher IU predicted downward trends in generalised anxiety over time. This suggests that IU is associated with generalised anxiety across childhood but is unlikely to play a causal role in the onset of generalised anxiety. Following this, Study 2 explored the relationship between IU and children’s behaviour and affect under uncertainty. This study also examined the role of curiosity to tease apart effects of IU from curiosity. IU was not found to predict children’s emotional responses, however children did seek more information under higher uncertainty than lower uncertainty, but this was not related to either IU or curiosity. Lastly, Study 3 replicated Study 2 but with adult participants. Those higher in IU were more worried and had more negative affect than those with lower IU, particularly in high uncertainty trials, but they did not seek more information. Overall, these studies provide new knowledge about developmental associations between IU and generalised anxiety and advance current understanding of the construct of IU and how it is associated with behavioural, cognitive and emotional responses to uncertainty. Future priorities lie in psychophysiological, observational and qualitative work with children.