Optimal Sound-Color Matching Scheme of Five-Element Music and Lighting Colors for Emotional Responses in Patients with GAD: A Randomized, Two-Factor Mixed-Design Trial.

BACKGROUND

Sound-color matching offers a novel approach to enhance music therapy, but the optimal combinations for emotional dysregulation in generalized anxiety disorder (GAD) remain untested.

OBJECTIVE

To identify the optimal sound-color matching scheme for emotional responses in GAD patients using Five-Element music and different lighting colors.

METHODS

A randomized two-factor mixed-design trial was conducted between June 2024 and February 2025 at Grade-A tertiary hospitals. Lighting color (cyan, red, yellow, white, black) was the between-subjects variable, and musical emotional valence (positive, neutral, negative) was the within-subjects variable. 210 eligible GAD patients were randomly assigned to five lighting color groups. The audiovisual stimulation combined calibrated LED lighting and validated Five-Element music segments in a standardized laboratory environment. Primary outcomes were subjective valence and arousal scores (Self-Assessment Manikin). Secondary outcomes included skin conductance (SC), skin temperature (ST), heart rate (HR), and electroencephalography (EEG) power spectral density (PSD).

RESULTS

All 210 patients were included in the subjective data analysis, with 205 providing valid physiological data and 204 yielding EEG data. Significant interactions between lighting color and music valence were observed for valence scores (F=2.02, p<0.050), arousal scores (F=2.77, p<0.050), ST (F=51.18, p<0.050), and HR (F=39.77, p<0.050). Cyan lighting with positive music produced the highest valence scores (7.79±0.81) and optimal physiological regulation (lowest HR: -15.44±1.89 beats per minute (bpm); highest ST: 0.84±0.09°C). Red lighting with positive music induced the highest arousal (6.83±1.23). EEG analysis revealed a significant interaction only in the theta band (F=1.98, P=0.024), with positive music showing lower PSD across all bands.

CONCLUSION

Among the tested pairings, positive Five-Element music with cyan lighting elicited the most favorable immediate emotional and physiological responses in patients with GAD, supporting further investigation of sound‑color matching as a multimodal adjunctive strategy for emotional regulation.

TRIAL REGISTRATION: This clinical trial was registered at the Chinese Clinical Trial Registry (clinical trial number: ChiCTR2400079878).