Depression is categorized under the Axis I disorder.
A general over-lap of causes and factors may exist between depression and generalized anxiety disorder, as well as the depressive stage in Manic-Depression condition. But, the key symptoms which help differentiate an purely depressed person, includes their over all dullness in character, a morbid and dismal look about them, and over bearing reliance on as well as being hung up in the past, on regrets, feeling guilty, seeing past mistakes and life experiences as a sorry string-along, due to which the present and future gets neglected, is ignored and the focus on the individual's everyday living is brooding over own past, in dismay and dejection.
In Manic-Depressive condition, the affect, behavior ...
Clinical Psych: depression and manic-depression/challenges in assessment, differential diagnosis, and use of psychopharmacological and non-pharmacological treatment