Author: Norman A S Farb1,2, Zoey Zuo2, Cynthia J Price3
1 Department of Psychology, University of Toronto Mississauga, Mississauga, Ontario, Canada, L5L 1C6 firstname.lastname@example.org.
2 Department of Psychological Clinical Sciences, University of Toronto Scarborough, Scarborough, Ontario, Canada, M1C 1A4.
3 Department of Biobehavioral Nursing and Health Informatics, University of Washington, Seattle, Washington, USA, 98195.
Date published: 2023 Jun 14
Other: Special Notes: doi: 10.1523/ENEURO.0088-23.2023. , Word Count: 357
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 interoceptive attention 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 completed the IEAT during two separate scanning sessions (N = 44) as part of a randomized control trial of Mindful Awareness in Body-oriented Therapy (MABT). Compared to Active Exteroception, Active Interoception deactivated somatomotor and prefrontal regions. Greater self-reported interoceptive sensibility (MAIA scale) predicted sparing from deactivation within the anterior cingulate cortex (ACC) and left-lateralized language regions. The right insula-typically described as a primary interoceptive cortex-was only specifically implicated by its deactivation during an exogenously paced respiration condition (Active Matching) relative to self-paced Active Interoception. Psychophysiological interaction (PPI) analysis characterized Active Interoception as promoting greater ACC connectivity with lateral prefrontal and parietal regions commonly referred to as the Dorsal Attention Network (DAN). In contrast to evidence relating accurate detection of liminal interoceptive signals such as the heartbeat to anterior insula activity, interoceptive attention towards salient signals such as the respiratory cycle may involve reduced cortical activity but greater ACC-DAN connectivity, with greater sensibility linked to reduced deactivation within the ACC and language-processing regions.Significance StatementInteroception, the representation of the body's internal state, is poorly understood compared to the external senses, with existing neuroimaging studies failing to match task difficulty between interoceptive and exteroceptive tasks. The present study used a novel fMRI task to compare interoceptive and exteroceptive attention and explore whether this distinction was moderated by self-reported interoceptive awareness. The results implicate three novel interoceptive mechanisms: interoceptive attention reduces widespread cortical activity while increasing prefrontal connectivity, wherein greater self-reported interoceptive awareness is linked to preserved activation of the anterior cingulate cortex and language regions. Rather than increasing activation of interoceptive cortex, interoceptive attention to the breath may involve attending to body representations typically ignored in favor of exteroceptive information and other forms of cognition.
Keywords: Attention; Awareness; Interoception; Respiration; Sensibility; fMRI.
PMID: 37316296 DOI: 10.1523/ENEURO.0088-23.2023