Fig. 4From: Enhancement of autonomic and psychomotor arousal by exposures to blue wavelength light: importance of both absolute and relative contents of melanopic componentMean heart rate and heart rate variability indices during five sessions of blue, green, and white light exposures in ten subjects in the main study. Error bars indicate standard error of the means. HF high-frequency component, LF low-frequency component, LF/HF LF-to-HF ratio in powerBack to article page