title: The integration of the internal and external milieu in the insula during dynamic emotional experiences.
abstract: Whilst external events trigger emotional responses, interoception (the perception of internal physiological states) is fundamental to core emotional experience. By combining high resolution functional neuroimaging with concurrent physiological recordings, we investigated the neural mechanisms of interoceptive integration during free listening to an emotionally salient audio film. We found that cardiac activity, a key interoceptive signal, was robustly synchronised across participants and centrally represented in the posterior insula. Effective connectivity analysis revealed that the anterior insula, specifically tuned to the emotionally salient moments of the audio stream, serves as an integration hub of interoceptive processing: interoceptive states represented in the posterior insula are integrated with exteroceptive representations by the anterior insula to highlight these emotionally salient moments. Our study for the first time demonstrates the insular hierarchy for interoceptive processing during natural emotional experience. These findings provide an ecologically-valid framework for elucidating the neural underpinnings of emotional deficits in neuropsychiatric disorders.
authors.affiliation: QIMR Berghofer Medical Research Institute, Herston, QLD, Australia.
authors.forename: Vinh Thai
authors.initials: VT
authors.lastname: Nguyen
authors.affiliation: QIMR Berghofer Medical Research Institute, Herston, QLD, Australia; Black Dog Institute, Sydney, Australia.
authors.forename: Michael
authors.initials: M
authors.lastname: Breakspear
authors.affiliation: School of Automation, Northwestern Polytechnical University, Xi'an, China.
authors.forename: Xintao
authors.initials: X
authors.lastname: Hu
authors.affiliation: QIMR Berghofer Medical Research Institute, Herston, QLD, Australia. Electronic address: christine.cong@gmail.com.
authors.forename: Christine Cong
authors.initials: CC
authors.lastname: Guo
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D001307:Auditory Perception / Q000502:physiology; D001341:Autonomic Nervous System / Q000502:physiology; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000502:physiology*; D004644:Emotions / Q000502:physiology*; D005260:Female; D006339:Heart Rate; D006801:Humans; D065812:Interoception / Q000502:physiology*; D008279:Magnetic Resonance Imaging; D008297:Male; D055815:Young Adult
keywords: Dynamic causal modelling; Heart rate variability; Insula cortex; Interoception; Naturalistic stimuli