Using Functional Near-Infrared Spectroscopy to Examine Consumer Stated Liking and Neuronal Responses to Regular and Light Variants of Coke and Potato Chips

This study examined differences in stated liking and prefrontal brain activation between regular and light versions of coke and potato chips using functional near-infrared spectroscopy (fNIRS). Thirty-one participants completed blind tastings of both variants, with water as a control. Stated liking was rated on a 7-point scale (before the tasting), and neuronal activation was analyzed with a General Linear Model at p < 0.10 (Bonferroni-corrected). Regular products received significantly higher liking scores than light variants ( p < 0.05). Both types evoked distinct prefrontal activation patterns compared to water, but no significant group-level neural differences appeared between regular and light versions ( p > 0.10). Subgroup analyses showed stronger activation in the dorsolateral and ventrolateral prefrontal cortex for likers of the respective product ( p < 0.10). Caloric reduction did not markedly alter cortical responses but influenced general evaluation, highlighting how fNIRS can reveal neural correlates of consumer preference for healthier foods.