Individual differences in anxiety and fear learning: The role of working memory capacity

Anxiety disorders are characterised by the perception of fear and threat in the presence of stimuli that are neutral or ambiguous. Attempts in previous research to explain the relationship between anxiety and fear learning have been inconsistent, possibly due to the influence of an unmeasured mechanism that mediates the relationship between them. Working memory capacity has been suggested as one such mechanism. The current study investigated the influence of anxiety-based individual differences upon associative fear learning, while accounting for individual differences in working memory. We hypothesised that individuals high in both anxiety and working memory would show unimpaired fear learning whereas individuals high in anxiety and low in working memory would exhibit dysfunctional fear learning. Sixty participants completed a battery of anxiety and working memory tests, as well as a fear conditioning experiment that tested for blocking, conditioned inhibition and fear discrimination. We found that anxious individuals were more likely to show impaired fear discrimination only if they also had a low working memory capacity. Furthermore, anxiety was particularly associated with poorer learning about safety cues. Such relationships were not observed for blocking and conditioned inhibition. These results suggest that the relationship between anxiety and fear learning is complex and warrants further investigation of the potential mediating role of higher-order cognitive faculties.