Electrode-Level EEG Assessment of Sequential Taste and Packaging Exposure in Processed Foods: An Exploratory Study

Abstract

This study examined whether sustained electrode-level neural signals differentiate successive stages of a commercial food encounter and whether response patterns vary by gender. Fifty adults (25 male, 25 female; 20–40 years) completed a fixed protocol comprising a composite baseline, post-ingestive viewing of a branded product while residual flavor remained, later viewing of the same product under a recall instruction, and viewing of an unrelated snack product. Signals were acquired from eight scalp channels using a portable system, filtered at 0.5–45 Hz, notch-filtered at 50 Hz, common-average referenced, and aggregated into participant-level mean device-native amplitudes. Electrode-specific 4 × 2 mixed-design repeated-measures ANOVAs tested Condition, Gender, and their interaction; Greenhouse–Geisser correction addressed sphericity violations, and Benjamini–Hochberg adjustment controlled the false discovery rate. Condition effects were significant at all eight electrodes (all q ≤ 0.028), with partial ηp² ranging from 0.073 at O1 to 0.523 at C3 and the largest effects at C3, C4, and F4. Baseline-to-post-ingestive viewing yielded the broadest adjusted paired differences. Neither the Gender main effect nor the Condition × Gender interaction remained significant after correction, while individual trajectories showed marked heterogeneity. Portable low-density recordings therefore detected sequence-associated sensor-level differentiation across the protocol. Because condition was confounded with serial position, the baseline combined eye states, package stimuli were unmatched, amplitudes were uncalibrated, and behavioral validation was absent, the findings do not establish causal effects of flavor, product identity, recall, preference, cortical source, or consumer choice. Randomized, counterbalanced, behaviorally validated, and higher-density replication is required.