Tasting emotions: An in-depth fmri study exploring gustatory and visual cross-modal associations across various spatio-temporal regions of the human brain

This study investigates how taste influences emotional face recognition, focusing on the cross-modal interaction between gustatory and visual stimuli. While prior research has primarily examined how visual cues modulate taste perception, the reverse direction-how taste shapes visual processing in emotional contexts-remains underexplored. Using a combination of task-based functional MRI (task-fMRI) and resting-state fMRI (rs-fMRI), we examined the neural mechanisms by which taste modulates the perception of emotional faces. Behaviorally, sour tastes facilitated faster recognition of disgusted faces, while sweet tastes enhanced the detection of pleasant expressions. Neuroimaging results revealed that these emotionally congruent taste-face pairings elicited distinct activation patterns in the early visual cortex, including a significant interaction effect in the right calcarine gyrus (primary visual cortex, V1). Task-fMRI also showed modulation in the medial cingulate gyrus, fusiform gyrus, and superior frontal regions depending on emotional congruency. Resting-state fMRI revealed sustained alterations in intrinsic connectivity within the medial cingulate and paracingulate cortex following cross-modal dissonance, suggesting lasting neural effects beyond stimulus presentation. Together, these findings demonstrate the dynamic and enduring influence of taste on emotional face processing and offer novel insights into the neural basis of multisensory affective integration. By integrating task-based and resting-state fMRI, this study provides a comprehensive framework for understanding how affectively salient gustatory inputs shape social perception through both early perceptual and sustained neural mechanisms.