Evening will appear to fall earlier as clocks are set back an hour this weekend in most of the United States. People who experience Seasonal Affective Disorder (SAD), particularly in the Pacific Northwest's rain and gloom, know this time of year often triggers their condition.

Dr. Heidi Combs, a professor of psychiatry and behavioral sciences at the University of Washington School of Medicine, treats several patients for SAD and has advice about when to seek medical treatment.

“When it's starting to impair function, that is the time that you want to seek help to figure out what's going on, because it's a highly treatable disorder,” she said. “We don't want people out there suffering when there's great treatments available for them.”

[In downloadable video assets, Combs explains how light treatment can help to lessen the effects of SAD.]

Read our blog post to learn more about diagnosis and treatments for SAD.