Natural daylight is the primary ‘external environmental’ influencer of human performance and mood.
Our circadian rhythm, the body’s barometer of emotional state, responds most positively above all other external environmental influencers, to the solid ‘non flicker’ and even distribution horizontally and vertically that natural daylight delivers – leading to increased production of neurotransmitters such as serotonin, which in turn leads to greater mental stimulation.
Why is sunlight s good for you? SAD disorder – it’s a thing!
http://time.com/4888327/why-sunlight-is-so-good-for-you/