Co-localization and neuromodulation of interoceptive and emotional processes in the insular cortex.

Contrary to classical doctrines, our daily introspective experience, and clinical and scientific evidence, indicate that inner bodily signals substantiate emotions and intimately shape cognition. The anterior insular cortex (AIC), a prime target in neuropsychiatric disorders, recently emerged as a crucial interface between sensory inputs related to bodily physiology (i.e. interoception) and emotional and cognitive processes underlying subjective feelings. Using complementary expertise from two groups, the present project aims at localizing regions of interoceptive and emotional overlap in AIC, and causally proving AIC’s involvement in integrating these two signals. First, building on our recent work in anesthetized animals, we will use concurrent high-resolution brain imaging and neural signal recordings to map and characterize the representation of interoceptive signals in AIC in alert animals. Next, we will examine whether ‘positive’ and ‘negative’ emotional visual stimuli, known to recruit distinct eye gazing strategies, differentially activate this representation. Finally, using electrical vagal nerve stimulation and optogenetic AIC inhibition, we will test whether perturbations of interoception alter emotional gazing strategies in a manner that requires the insula. This work will provide fundamental information on the neurobiological substrate underlying ‘body-mind’ interactions, with clear implications for our understanding of psychosomatic or gut-brain axis disorders.