Anxiety makes time pass quicker: neural correlates

Anxiety can be an adaptive process that promotes harm avoidance. It is accompanied by shifts in cognitive processing, but the precise nature of these changes and the neural mechanisms that underlie them are not fully understood. One theory is that anxiety impairs concurrent (non-harm related) cognitive processing by commandeering finite neurocognitive resources. For example, we have previously shown that anxiety reliably ‘speeds up time’, promoting temporal underestimation, possibly due to loss of temporal information. Whether this is due anxiety ‘overloading’ neurocognitive processing of time is unknown. We therefore set out to understand the neural correlates of this effect, examining whether anxiety and time processing overlap, particularly in regions of the cingulate cortex. Across two studies (an exploratory Study 1, N=13, followed by a pre-registered Study 2, N=29) we combined a well-established anxiety manipulation (threat of shock) with a temporal bisection task while participants were scanned using functional magnetic resonance imaging. Consistent with our previous work, time was perceived to pass more quickly under induced anxiety. Anxiety induction led to widespread activation in cingulate cortex, while the perception of longer intervals was associated with more circumscribed activation in a mid-cingulate area. Importantly, conjunction analysis identified convergence between anxiety and time processing in the insula and mid-cingulate cortex. These results provide tentative support for the hypothesis that anxiety impacts cognitive processing by overloading already-in-use neural resources. In particular, overloading mid-cingulate cortex capacity may drive emotion-related changes in temporal perception, consistent with the hypothesised role of this region in mediating cognitive affective and behavioural responses to anxiety.