Let there be "winter" light.

• Position: Your Life - Treating seasonal affective disorder

If the cold weather is leaving you grouchy, down in the dumps, lethargic, a bit heavier than usual, and finding your sleep patterns altered, you may have a case of seasonal affective disorder, or SAD. In searching for a cure, researchers are looking at timing light therapy with a patient's biorhythms; treating individuals with smaller, portable lights; and studying people's reactions to the seasonal absence of electrically-charged negative ions that occur naturally in the spring air.

"While some of these solutions are still in the research stage, I think the word has been out to people who get depressed in the winter that this is something that can be treated," stresses Paul Desan, director of the Winter Depression Research Clinic at Yale-New Haven (Conn.) Hospital.

SAD became an official diagnosis in the late 1980s. Optimum treatments, including antidepressants and light therapy, emerged in the 1990s. Studies estimate that about five percent of people who live in areas that are at about the same latitude as Connecticut suffer from true SAD; about three times that number report significant problems with mood, energy, and sleep during the winter months.

The current focus is on finding ways to make light exposure treatment more...