affective disorder

also called mood disorder

Any of several mental disorders characterized by dramatic changes or extremes of mood. The major affective disorders include bipolar disorder—which may include manic and depressive episodes—and major depressive disorder. Among the symptoms of manic episodes are elevated, expansive, or irritable moods, with hyperactivity, pressured (rapid and forced) speech, and inflated self-esteem. Depressive episodes and major depressive disorder are characterized by dejected moods, lack of interest in life, sleep disturbances, agitation, and feelings of worthlessness or guilt.

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