Neurobiologically Informed Phenomenology of the Schizophrenia Spectrum

Schizophrenia patients present heterogeneous symptom patterns. Similarly, neuroimaging studies indicate widespread but nonspecific structural and functional cerebral alterations. Dimensional approaches have been proposed as best suited to describe the phenomenology of schizophrenia. While neural correlates were demonstrated for single symptoms such as hallucinations or formal thought disorders, currently proposed dimensions cannot be easily linked to an underlying functional neuroanatomy. A new phenomenological framework of psychosis is proposed including three-symptom dimensions organized according to neurobiological information and relevance to human communication, i.e., language, affectivity, and motor behavior. Empirical evidence suggests that each of these three behavioral dimensions can be identified by a specific, operationalized symptom pattern and can be related to a distinct cerebral circuitry. In addition, these dimensions allow focusing on the intact communication resources of the patients and provide testable hypotheses to study pathophysiological pathways contributing to the schizophrenia syndrome. Preliminary findings using the Bern Psychopathology Scale (BPS) in neuroimaging and other studies support our theoretical assumption concerning the association between phenomenology and pathobiology.