FROM OCCIPITO-TEMPORAL CORTEX TO FRONTAL AND PERISYLVIAN NETWORKS: PATHWAYS FOR EMOTIONAL AND MOTOR RESONANCE

The perception of emotional facial expressions recruits distributed networks extending beyond occipito-temporal visual regions into frontal and perisylvian cortices. Intracranial evidence supports a dissociation between emotional/interoceptive resonance (anterior cingulate cortex, anterior insula) and motor resonance (Rolandic operculum) during passive observation, suggesting that this ability relies on partially distinct networks (Del Vecchio et al., 2024). However, the anatomical and functional organization of these networks and the pathways through which visual information reaches them remain poorly understood.

Here, we combined diffusion tensor imaging (DTI) and resting-state fMRI to identify anatomical pathways linking visual and frontal/perisylvian regions and to characterize their interactions. Regions of interest were defined based on intracranial sites responsive to emotional faces (Del Vecchio et al., 2024). Temporal dynamics were analyzed using intracranial event-related potentials recorded from occipito-temporal and frontal/perisylvian regions in 44 epilepsy patients. DTI and resting-state fMRI analyses revealed that frontal and perisylvian territories participate in three circuits corresponding to the Salience, Sensorimotor, and Dorsal Attention networks. The first two map onto limbic/prefrontal and premotor territories, while the third occupies a cognitive/attentional position linking the other systems, providing a framework for emotional/interoceptive and motor resonance processes. Electrophysiological findings showed prominent facial expression–related activity in ventral occipito-temporal regions, suggesting a preferential route to resonance systems. Together, these results provide evidence for a tripartite architecture comprising emotional/limbic, premotor, and cognitive/attentional networks, through which information conveyed by parallel occipito/temporal pathways. Their integration supports emotional and motor resonance, enabling adaptive responses to social stimuli.