What is a Mood Disorder?
Ordinarily, people experience a wide range of moods and have an equally large repertoire of affective expressions; they feel in control more or less of their moods and affects. In mood disorders, the sense of control is lost, and people experience distress. People with an elevated mood (mania) can show expansiveness, flight of ideas, decreased sleep, heightened self-esteem and grandiose ideas. People with depressed mood (depression) can have a loss of energy and interest, feelings of guilt, difficulty in concentrating, loss of appetite and thoughts of death or suicide.
Source: Synopsis of Psychiatry, Kaplan & Sadock, 1998.
Related Resources and Sites Source: http://www.psyweb.com/Mdisord/moodd.html#df