Introduction
RECRUITMENT
Interoception, the sense of the body’s internal state, is central to human experience, providing homeostatic cues (Our understanding has been limited by a focus on interoceptive accuracy by the research community. For example, heartbeat detection paradigms model the ability to detect a liminal cardiac signal (Research confirms that interoceptive accuracy may not be especially relevant for emotion regulation and wellbeing. Clinical populations often show normal interoceptive accuracy (Interoceptive attention tendency, and specifically the ability to sustain interoceptive attention remains a compelling if underexplored determinant of mental health (Interoceptive attention seems to recruit a distinct neural network from exteroception that features the middle insula (Yet neuroimaging studies characterizing interoceptive attention to the breath have been confounded by nonequivalent task demands. We therefore developed a novel fMRI paradigm for characterizing the neural dynamics of breath-focused interoception compared with a closely balanced exteroception task. We hypothesized (H1) that interoception would result in greater somato-insular recruitment than exteroception, but reduced DAN activation. We further hypothesized (H2) that greater self-reported interoceptive sensibility would correlate with greater SLN activity during interoception, consistent with the SLN’s ascribed role in sensory monitoring and integration (