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Major Depressive Disorder

  1. Erin S. Sheets1,
  2. Alisha L. Brosse2

Published Online: 30 JAN 2010

DOI: 10.1002/9780470479216.corpsy0522

Corsini Encyclopedia of Psychology

Corsini Encyclopedia of Psychology

How to Cite

Sheets, E. S. and Brosse, A. L. 2010. Major Depressive Disorder. Corsini Encyclopedia of Psychology. 1–2.

Author Information

  1. 1

    Brown University Medical School and Butler Hospital

  2. 2

    University of Colorado at Boulder

Publication History

  1. Published Online: 30 JAN 2010


Major depressive disorder (MDD) is characterized by depressed mood or a lack of interest or pleasure in once-enjoyable activities, and associated symptoms (e.g., sleep disturbance; appetite/weight disturbance; difficulty concentrating; feelings of worthlessness or exaggerated guilt). To receive a diagnosis of MDD, at least five symptoms must be present most of the day, nearly every day, for at least two weeks (American Psychiatric Association [APA], 2000).


  • major depression;
  • relapse;
  • recurrence