[Aetiology of depressive disorders--the biopsychosocial model].
The biopsychosocial model has been developed from general system theory and describes the interaction of body and mind. Unipolar depression has a complex pathogenesis which on an individual level presents in very diverse ways. The article focuses on biological factors such as heritability, changes in neurotransmitters, endocrinological factors and chronobiological patterns. The psychosocial factors include critical life events, social pressure, cognitive and learning theory-based factors as well as personality factors.It was found that the biological, psychological and (eco-) social factors that contribute to etiopathogenesis frequently interact. The biopsychosocial model lends itself to collecting all the factors that are linked to a depression etiopathogenetically and to using them for the purpose of diagnostics.It thus provides a suitable basis for individually tailored therapy and also has valuable applications in the field of psychoeducation.