Abstract

Mixed states are frequent clinical pictures in psychiatric practice but are not well described in nosologic systems. Debate exists as to defining mixed states. We review factor and cluster analytical studies and prominent clinical/conceptual models of mixed states. While mania involves standard manic symptoms and depression involves standard depressive symptoms, core additional features of the mixed state are, primarily, psychomotor activation and, secondarily, dysphoria. Those features are more pronounced in mixed mania than in mixed depression but are present in both.