Affective Disorder is a mood disorder characterized by depression
which occurs at a particular time of the year (usually winter).
The symptoms include fatigue, apathy and loss of concentration.
SAD usually occurs only in adults, and in women more frequently
than men. It is thought that SAD may be triggered or exacerbated
by the lack of sunlight during winter months, and in fact
SAD is more common in northern latitudes, where there may
be only a few hours of sunlight during winter days.
Individuals suffering from SAD often benefit
from light therapy, which involves daily exposure to lights
designed to produce the same kind of radiation as sunlight;
they may also benefit from counseling, exercise, stress management
and antidepression medication.
by Catherine E. Myers. Copyright © 2006 Memory Loss and the Brain