Insula Interoception, Active Inference and Feeling Representation

TL;DR

This paper proposes a hierarchical modular model of the insula's role in interoception, linking its structure to higher-order visceral representations and conscious feelings, integrating neural architecture with adaptive behavior.

Contribution

It introduces the IMAC model, detailing insula modules' interactions with prefrontal and striatal regions for complex interoceptive processing and emotional experience.

Findings

Insula modules are specialized for higher-order interoceptive representations.

These modules form networks with prefrontal and striatal regions for adaptive behavior.

Interoceptive representations may give rise to conscious feelings.

Abstract

The body sends interoceptive visceral information through deep brain structures to the cerebral cortex. The insula cortex, organized in hierarchical modules, is the major cortical region receiving interoceptive afferents and contains visceral topographic maps. Yet, the biological significance of the insula's modular architecture in relation to deep brain regions remains unsolved. In this opinion, we propose the Insula Hierarchical Modular Adaptive Interoception Control (IMAC) model to suggest that insula modules (granular, dysgranular and agranular subregions), forming networks with prefrontal (supplementary motor area, dorsolateral and ventromedial cortices) and striatum (posterior, dorsomedial and ventromedial) subregions, are specialized for higher-order interoceptive representations, recruited in a context-dependent manner to support habitual, model-based and exploratory adaptive behavior. We then discuss how insula interoceptive representations, or metaceptions, could give rise to conscious interoceptive feelings built up from low-order visceral representations and associated basic emotions located in deep interoceptive brain structures.