Abstract
Impaired breathing-related interoceptive abilities have been associated with many adverse outcomes, including high levels of trait anxiety. However, research has not yet considered the neural connectivity patterns which might underpin these poor interoceptive abilities, and how this may relate to anxiety. Identifying the brain connectivity linked to interoception of breathing within a healthy population provides insight into the neural processes that permit adaptive brain-body communication as well as instances where this communication goes awry. To investigate the neural patterns associated with breathing-related interoceptive abilities, 65 healthy participants underwent a resting-state magnetic resonance imaging session and completed both a breathing-related interoceptive task and a trait anxiety questionnaire. The breathing task provided measures of four aspects of interoceptive ability which were analysed alongside trait anxiety as predictors of the resting-state data. We observed that connectivity between the bilateral amygdala and insula cortex was linked to the level of confidence ascribed to respiratory-related interoceptive judgements (metacognitive bias), while left-lateralised connectivity between the amygdala and insula cortex was associated with a worsened ability to detect an inspiratory resistance (interoceptive sensitivity). Both reductions in confidence and sensitivity correlated with heightened trait anxiety levels at a behavioural level. However, the connectivity differences across levels of metacognitive bias and interoceptive sensitivity were only minimally mediated by healthy levels of trait anxiety. Therefore, our findings indicate that within a healthy population, the resting-state connectivity between the amygdala and the insula cortex is linked to breathing-related interoceptive processes in a manner that is largely independent of anxiety. Conversely, the broader literature suggests this neural dissociation of interoceptive and anxiety outcomes may not be a feature of clinical anxiety populations. Thus, the results of this project may offer critical insights into the differences between healthy and clinical levels of trait anxiety, serving as an interesting foundation for future investigations.