One driver contemplates the meaninglessness of it all during a snowfall. (Photo: Lori Holder-Webb/Flickr)

Feeling a little down lately? You're not alone. Most Americans turned back their clocks on Sunday, which means this week was the first they left work after the sun went down. Those with seasonal affective disorder, or SAD, might find themselves wanting to go straight home and hibernate, says Kelly Rohan, a clinical psychologist who studies SAD at the University of Vermont. Forget the gym. And definitely forget that potluck. Better to wallow in misery.

Rohan got interested in SAD when she was a graduate student at the University of Maine. She and her co-workers were always trying to recruit volunteers for studies about depression, but she noticed they only succeeded in certain months: "We were beating them away with a stick in the fall and winter and in the spring and summer, you could hear crickets in the lab," she says.

Clinical psychologist Kelly Rohan sits in front of a light box. (Photo: Andy Duback)

Since then, scientists have found one treatment to combat SAD: Those super-bright "light boxes" designed to mimic the sun. Rohan, however, has been busy checking if something else might work better: Cognitive behavioral therapy. In her new study in the American Journal of Psychiatry, Rohan and her colleagues found that, among 177 SAD patients in Vermont and New York, light boxes and cognitive behavioral therapy worked equally well initially. But two years later, participants who were assigned to undergo cognitive behavioral therapy were less likely to record depressive episodes than those assigned to use light boxes. "My interpretation of this is these are both are effective treatments, but it seems that getting the cognitive therapy gives you more bang for your buck, in terms of staying well over time," Rohan says.

"Getting the cognitive therapy gives you more bang for your buck."

Cognitive behavioral therapy teaches people to recognize when they're feeling depressed, and to try to think more positively. It also teaches them to remain as active as they'd been in the spring and summer. There's no science yet to explain why the therapy might work better in the long run, but Rohan thinks part of the problem is that light boxes relieve depression only so long as people use them. People might just get tired of having to sit in front of their light boxes for up to an hour every morning during winter. Cognitive behavioral therapy, on the other hand, teaches people novel ways of thinking that they're able to draw on whenever they need.

Some treatment guidelines for doctors, such as the Canadian Consensus Guidelines for the Treatment for Seasonal Affective Disorder, list only light boxes and anti-depressant medicines as therapies for SAD. Rohan wants to see cognitive behavioral therapy added to the list. There's still much more research on light boxes than on cognitive behavioral therapy, but there's enough to consider the latter an option, Rohan thinks.

Meanwhile, she hopes to receive a grant to continue collecting evidence for cognitive behavioral therapy. As for you, it's probably a good idea to go to the gym tonight, and to that potluck.

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