Researchers have found that exposure to blue light can increase alertness in humans. Participants exposed to blue light versus green light were rated more alert and less sleepy. This finding can be extremely useful in improving performance and warding off fatigue. To read the complete article on how blue light has an alerting effect go to http://www.brighamandwomens.org/about_bwh/publicaffairs/news/publications/DisplayBulletin.aspx?articleid=6222