Brain signature of food and alcohol stimuli processing: a comparative EEG study

Food and alcohol cues are potent motivational stimuli that engage neural systems supporting reward and approach-avoidance behavior. While EEG studies have largely emphasized event-related potentials, less is known about how sustained oscillatory dynamics differentiate appetitive cues with distinct biological and learned significance.

EEG activity was recorded in healthy adults during passive viewing of food-related, alcohol-related, and matched neutral images using a paradigm optimized for prolonged exposure. Spectral power was analyzed across canonical frequency bands with cluster-based permutation statistics. Individual differences in alcohol use were assessed using the Alcohol Use Disorders Identification Test (AUDIT). Additional psychometric assessments included measures of depression (BDI-II), trait anxiety (STAI-Trait), eating behavior (DEBQ), and nicotine dependence (Fagerström).

Food and alcohol cues elicited dissociable oscillatory responses. Food images were associated with increased delta-band power over posterior and central regions, whereas alcohol images induced decreased delta power and increased alpha-band activity over parieto-occipital areas. These effects were most pronounced in individuals with higher AUDIT scores, while lower-AUDIT scorers showed no consistent oscillatory modulation. Psychometric scores indicated non-clinical levels of depression and anxiety across participants.

The findings indicate that food and alcohol cues engage partially distinct oscillatory dynamics during passive viewing. EEG spectral measures capture sustained, state-dependent aspects of motivational processing, highlighting differences between biologically grounded and learned reward cues.