Neural Dynamics of Interoceptive Attention and Awareness: A Within-Participant fMRI Study

Abstract

Interoception, the representation of the body’s internal state, serves as a foundation for emotion, motivation, and wellbeing. Yet despite its centrality in human experience, the neural mechanisms of interoception are poorly understood. The Interoceptive/Exteroceptive Attention Task (IEAT) is a novel neuroimaging paradigm that compares behavioral tracking of the respiratory cycle (Active Interoception) to tracking of a visual stimulus (Active Exteroception). Twenty-two healthy participants attended two separate scanning sessions (N=44 scans) during a randomized control trial of Mindful Awareness in Body-oriented Therapy (MABT). Compared to Active Exteroception, Active Interoception led to widespread cortical deactivation. Greater self-reported interoceptive awareness (MAIA scale) predicted sparing from deactivation along the anterior cingulate cortex (ACC) and left lateral prefrontal cortex. The right insula- typically described as a primary interoceptive cortex- was only specifically implicated by its deactivation during a paced respiration condition (Active Matching), relative to both Active Exteroception and Interoception. Instead, psychophysiological interaction analysis characterized Active Interoception as promoting greater ACC connectivity with lateral frontal and parietal regions commonly referred to as the Dorsal Attention Network. By comparing attention between highly accessible interoceptive and exteroceptive stimuli, these findings recast interoceptive attention as broadly inhibitory, linking greater interoceptive awareness to spared cortical inhibition within well-characterized attentional networks. In contrast to a literature that relates detection of liminal signals such as the heartbeat to anterior insula activity, attention towards accessible body sensations such as the breath may lead to a context of cortical inhibition in which sensory signals from the body may be better discerned.