Gender Differences in Brainwave and Emotional Responses to Lightness and Chroma Variations of Purple Eyeshadow

Purpose: This study aimed to inform cosmetic color planning strategies by examining gender differences in brainwave activity and emotional evaluations elicited by purple eyeshadow stimuli that systematically vary in lightness and chroma.Methods: A total of 60 adult participants (30 males, 30 females) viewed purple eyeshadow sets across two variation series. Their brainwave responses were assessed using the coefficient of variation for brainwave power relative to their baseline EEG, while their emotional responses were measured using an average preference index (API) derived from semantic differential scales. Data were subjected to repeated-measures analysis of variance.Results: Low-lightness stimuli significantly increased β, γ, SEF50, and SEF90 whereas high-lightness stimuli enhanced α activity, suggesting relaxation. High-chroma conditions elicited stronger β, γ, SEF50, and SEF90 responses with less reduction in α activity compared with low-chroma stimuli. Hence, dark, saturated colors were associated with arousal and attentional activation, while lighter, less saturated tones promoted relaxation. Based on API results, positive evaluations were observed at intermediate lightness levels (6 and 8), with gender-specific differences in emotional responses despite generally consistent brainwave patterns.Conclusion: Physiological and psychological responses to cosmetic colors are more strongly influenced by lightness adjustments than by chroma. Thus, effective cosmetic color planning should prioritize lightness modulation while incorporating gender-specific preferences.