According to Diagnostic Criteria from DSM-IV-TR, depression is consider a mood disorder. Major depressions Episode, Manic Episode, Mixed Episode, Hypomanic Episode, are some of the types of depression. Each type has different criteria to meet to be considered as the type of depression.
Major depression Episode must show five or more symptoms during the same two week periods. The symptoms would be depressed most of the day or nearly everyday. There is significant weight gain or loss; the person may feel insomnia or hypersomnia nearly every day, fatigue or loss of energy nearly everyday, feeling of worthlessness, excessive or inappropriate guilt, diminished ability to think or concentrate, and/or recurrent thoughts of death. Also, the symptoms are not due to the direct physiological effects of substance.
Manic Episode is different because a distinct period of abnormally and persistently elevated, expensive or irritable mood is lasting at least one week. There should be three or more symptoms. They symptoms are inflated self-esteem or grandiosity, decreased need of sleep, more talkative, flight of ideas, distractibility, increase in goal-directed activity, and excessive involvement in pleasurable activities.
In comparicent, mixed episode is combining of major depression episode and manic episode nearly every day during a one week period. This could cause impairment in occupational functioning or usual social activities or relationships with others.
Hypomanic episode is a distinct period of persistently elevated, expansive or irritable mood. It would have three or more symptoms. The symptoms would be inflated self-esteem or grandiosity, decreased need for sleep, more talkative than usual,...