Multimodal evidence of interoceptive dimensions in 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.

Munich

Conferencia; 10th International Conference on Frontotemporal Dementias; 2016

International Society for Frontotemporal Dementias

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 skills. 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.