Given what we know about seasonal affective disorder (SAD)—namely, that it’s a form of depression that kicks in during the winter when days get shorter and darker—and that light therapy is an effective treatment for SAD, it’s safe to say that a sunrise alarm clock may benefit those with other types of depression. In fact, research has indicated that bright light therapy may be an effective, fast-acting therapy for non-seasonal forms of depression as well, including major depressive disorder (MDD).