The functional neuroanatomical organization of interoceptive dimensions: Multimodal evidence from neurodegeneration and stroke

GARCÍA-CORDERO, I., SEDEÑO, L., TORRALVA, T., DE LA FUENTE, L., FERRARI, J., RODRIGUEZ, C., BAEZ, S., YORIS, A., ESTEVES, S., MELLONI, M., SALAMONE, P., MANES, F., GARCÍA, A. M. & IBAÑEZ, A.

La Havana

Congreso; 18th World Congress of the International Organization of Psychophysiology; 2016

International Organization of Psychophysiology

Interoception encompasses multiple dimensions and relies on widespread neural hubs. To examine neurocognitive process in such brain network, we assessed cardiac interoceptive accuracy, learning, and awareness in healthy subjects and patients offering contrastive lesion models of neurodegeneration and stroke: behavioral variant frontotemporal dementia (bvFTD), Alzheimer?s disease (AD), and fronto-insular stroke. Neural correlates of the three dimensions were examined through structural and functional resting-state imaging and online measurements of the heart-evoked potential (HEP). The three patient groups presented deficits in interoceptive accuracy, associated to insular affectation, connectivity alterations, and abnormal HEP modulations. Interoceptive learning was differentially impaired in AD patients, suggesting a key role of memory skill. Interoceptive awareness results showed that bvFTD and AD patients overestimated their performance, indexed by abnormal anterior regions and associated networks engaged in to metacognitive process, and probably related to the well known insight deficits of this population. Findings specify how damage to specific hubs in a broad fronto-temporo-insular network compromises differentially interoceptive dimensions, and how such disturbances affect widespread connections beyond those critical hubs. This is the first study in which a multiple lesion model reveals fine-grained alterations of body sensing, offering new theoretical insights into neuroanatomical foundations of interoceptive dimensions.This work was partially supported by grants from CONICET, CONICYT/FONDECYT Regular (1130920 and 1140114), COLCIENCIAS (1115-545-31374, contract: 392), FONCyT-PICT 2012-0412, FONCyT-PICT 2012-1309, FONDAP 15150012, and the INECO Foundation.