Large-scale brain network interactions differentiate sweet, sour, and salty food cues during visual processing

Visual cues play an important role in food selection by providing early information about taste properties before consumption. However, the large-scale neural mechanisms underlying the perception of different tastes from visual food cues remain poorly understood. Using electroencephalography and whole-brain functional connectivity analysis, we conducted an exploratory, hypothesis-generating investigation of large-scale brain network responses to visual food cues associated with three basic taste qualities, including sweet, sour, and salty. We computed functional connectivity across 100 cortical parcels, and examined the distribution of significant connections across seven canonical brain networks. Brain network connectivity differed across taste categories. Sweet food images engaged default mode network connectivity with somatomotor and attention networks. Sour food images showed significant limbic and salience network connectivity, suggesting heightened affective evaluation. Salty food images evoked the most widespread engagement, with significant control network involvement alongside visual, default mode, and attention networks. Our findings suggest that large-scale network interactions vary with the inferred taste profile of visual food cues. This network-level characterization provides exploratory evidence for taste-associated brain-wide communication during visual food processing.