The authors review what has been learned about the causes, symptoms, and
treatments of seasonal affective disorder and discuss its relevance to
affective illness in general. They point out that seasonal and
environmental influences on depression have been themes in writings on
affective illness for more than 2,000 years and that there has been a
resurgence of interest during the past decade. There appear to be two
primary, opposite seasonal patterns of annual depression--winter depression
and summer depression--with opposite vegetative symptoms. Seasonal
affective disorder is not uncommon. It is important to identify patients
with winter depression because they respond to a specific treatment,
phototherapy.Abstract Teaser