Depressive disorders are characterized by sadness severe enough or persistent enough to interfere with function and often by decreased interest or pleasure in activities. Exact cause is unknown but probably involves heredity, changes in neurotransmitter levels, altered neuroendocrine function, and psychosocial factors. Diagnosis is based on history. Treatment usually consists of drugs, psychotherapy, or both and sometimes electroconvulsive therapy or rapid transcranial magnetic stimulation (rTMS). The term depression is often used to describe the low or discouraged mood that results from disappointments (eg, financial calamity, natural disaster, serious illness) or losses (eg, death of a loved one). However, better terms for such moods are demoralization and grief.
The negative feelings of demoralization and grief, unlike those of depression, do the following:
Occur in waves that tend to be tied to thoughts or reminders of the inciting event
Resolve when circumstances or events improve
May be interspersed with periods of positive emotion and humor
Are not accompanied by pervasive feelings of worthlessness and self-loathing