Purpose: Investigating how Munsell’s primary color (i.e., red eye shadow) influences human brain and emotional responses to establish foundational data for image formation. Methods: We analyzed the relative power differences in background brainwaves due to variations in five levels of brightness and saturation for each eye both in male and female individuals in their twenties. We used the coefficient of variation for brainwaves for our analysis. In addition, we assessed the preferences for altered red eye shadow and the emotional responses to determine the average preference index. We performed statistical analysis for brainwaves and emotional evaluations using repeated measure analysis of variance in SPSS, followed by post hoc testing with Tukey’s test at a 95% confidence level. Results: The brainwave and emotional responses obtained by presenting red eye shadow brightness and saturation modification-created stimuli revealed that both men and women exhibited beta and gamma wave activation and alpha wave inactivation upon low brightness and high saturation stimuli. Men were more sensitive to brightness stimuli, whereas women displayed higher-level variability in brainwave responses upon saturation changes. Both genders preferred red eye shadows with brightness and saturation levels of 8 and 2, respectively. The perceptual image responses indicated that stimuli with low or high brightness were perceived as modern and subtle or clear and cute, respectively. Medium or high saturation stimuli were perceived as clear and natural or associated with a modern image, respectively, by both genders. Conclusion: This study demonstrated the impact of various color stimuli on the human brain and emotions. We consider the obtained results as foundational data, which could be used in future image consulting or when crafting desired image presentations.