Bright light stimulates the release of serotonin, a neurotransmitter that improves mood and reduces melancholy. Unfortunately, being in a dimly lit environment makes people feel even more down and sluggish..!! Exposure to bright white screens has been shown to improve happiness, focus, sleep, and even athletic performance. What is the answer, then? White Screen! You heard correctly! Numerous scientists claim that by projecting pure white light, White Screen improves mood.