Alpha oscillations during sunscreen application associated with willingness to pay.

As one of the most critical experiential attributes of cosmetics, tactile sensation directly shapes the perception of cosmetic value. To investigate its neural underpinnings, a task was designed to investigate the relationship between electroencephalographic (EEG) signal activity elicited during sunscreen application and willingness to pay (WTP). A total of 25 participants applied 6 sunscreens in a randomized order on the dorsum of the hand. EEG signals were recorded synchronously during application, and WTP was collected afterward. Linear mixed-effects models (LMM) were used to examine the association between multiple EEG features-including emotional valence, arousal, and principal components extracted from spectral power in the alpha (8-12 Hz), beta (12-27 Hz) and gamma (27-40 Hz) bands-on log-transformed WTP. Only the second principal component of alpha power during the application phase (APPLY_α_PC2) showed a significant positive association with WTP (t = 4.000, p < 0.001). This component exhibited a distinct oscillatory topography characterized by alpha synchronization over prefrontal and parietal regions and alpha desynchronization over temporoparietal areas, suggesting a neural pattern that may reflect task-relevant cortical engagement during tactile experience. The specific neural state indexed by prefrontal-parietal alpha synchronization is more directly associated with WTP than conventional emotional indicators. This neural pattern could serve as a candidate objective marker for evaluating cosmetic application experiences in product development and sensory testing.