Psychopathology of stable and unstable mixed states: A historical view

The concept of mixed states was proposed at the end of last century by Krae pelin and Weygandt to confer unity to manic-depressive illness and to bette r differentiate this disease from dementia praecox, The concept has been fu rther elaborated by the Hamburg and Vienna schools (Mentzos and Berner, res pectively), and dichotomized in stable and unstable mixed states. Stable mi xed states represent a condition of the synchronic copresence of symptoms o f both polarities; unstable mixed states, or "mixed pictures." are characte rized by the rapid cycling of these symptoms. The former represent clinical expressions of bipolar disorder, and the latter represent trans-nosologica l conditions with multiple outcomes. Current North American nosology retain s the original Kraepelinian concept of stable mixed states and ignores the concept of unstable mixed states, which is very close to the concept of ult radian cycling proposed by Kramlinger and Post in 1996, Copyright (C) 2000 by W.B. Saunders Company.