Sweet taste modulates social-affective processing: Elevated explicit affective ratings and attenuated LPP differentiation

Sweet taste is associated with positive affect and interpersonal intimacy, but its influence on social-affective processing remains unclear. Across two ERP experiments, we examined how sweetness modulates explicit affective evaluations and late positive potential (LPP) differentiation of social information in heterosexual women. In Experiment 1 ( N = 32), participants evaluated romantic and friendship interaction pictures under sweet and control taste conditions. Sweetness increased overall valence and arousal ratings and attenuated romantic–friendship LPP differentiation, with a significant Taste × Picture Type interaction (\(\:{{η}ₚ}²\) = .139). In Experiment 2 ( N = 56), participants passively viewed positive, negative, and neutral opposite-sex interaction pictures in either a sweet or control group. A significant Group × Picture Type interaction (\(\:{{η}ₚ}²\) = .060) was observed, with smaller positive–neutral and positive–negative LPP differentiation in the sweet group than in the control group, as confirmed by Holm-corrected interaction contrasts. Together, these findings suggest that sweet taste modulates explicit affective evaluation and late-stage electrophysiological differentiation in distinct ways.