One of the most exciting and promising areas of sleep research has centered on the use of bright light in treating specific conditions. Light has been successfully used as therapy for patients suffering from a variety of circadian rhythm sleep disorders, as well as for depression. The theory behind why light has a positive impact on our ability to sleep and feel well rested relies upon the existence of 24-hour body clocks called circadian oscillators. These are genetic components that process through each day in much the same way that the inner workings of a clock do. They respond to bright light that strikes our eyes. Scientists have determined that these oscillators can be reset when exposed to bright light, so that through careful use of light exposure we can be programmed to awaken earlier or later. Light therapy can be accomplished in a number of different ways. Perhaps the easiest is through the purchase of a bright-light box. This can be used at home. So for a person who has difficulty falling asleep much before dawn and who can’t awaken before noon but who is then wide awake late at night, the cure would be light exposure to bright light for at least half an hour immediately after he awakens each day. The exposure to the light would cause the patient to awaken earlier each day, and the light exposure would also follow this schedule, occurring earlier each day, until he has reached a more normal schedule and can then stabilize himself by shortening the period of time of exposure. Taking a daily dose of 1 mg of vitamin B12 may also prove helpful. For those who do not want to go to the expense of purchasing a light box, the same effect can be achieved by spending several full days outside in the sunlight. The problem with this cure is that it is only temporary – those who have severe sleep disorders will find that without the extensive exposure to daylight, they will quickly fall back into their own cycle. Getting out and taking a walk every morning for a period of at least half an hour may be enough to keep the cycle stable. Light therapy can be used to solve a number of problems beyond those that arise organically. Employees who perform shift work can be helped to stay awake during night shifts thorough the use of bright light in the work environment. They may also find that they can help themselves to get better quality sleep during the daylight hours if when they are driving home from work in the morning hours they work hard to shield themselves from the daylight. Extremely dark glasses such as welder’s goggles will help, but it is most important for workers to head straight home and not spend any time out in the sunlight – this is often a challenging proposition. Similar approaches can be used by those who are traveling abroad and crossing multiple time zones. Wearing dark glasses during the daytime prior to a trip from east to west may help the body clock adjust itself, and increasing exposure to sunlight during the daytime may help as well.