Disentangling interoception: insights from focal strokes affecting the perception of external and internal milieus

摘要: Interoception is the moment-to-moment sensing of physiological condition body. The multimodal sources interoception can be classified into two different streams afferents: an internal pathway signals arising from core structures (i.e., heart, blood vessels, and bronchi) external body-mapped sensations chemosensation pain) peripersonal space. This study examines differential processing along these within insular cortex (IC) their subcortical tracts connecting frontotemporal networks. Two rare patients presenting focal lesions IC (insular lesion, IL) or its (subcortical SL) were tested. Internally generated interoceptive assessed through a heartbeat detection (HBD) task, while those externally triggered tapped via taste, smell, pain recognition tasks. A pattern was observed. patient showed impaired signal SL exhibited perception deficits. Such selective deficits remained even when comparing each with group healthy controls brain-damaged patients. These outcomes suggest existence distinguishable streams. Results are discussed in relation neuroanatomical substrates, involving fronto-insulo-temporal network for cognitive contextual integration.