gms | German Medical Science

Background: We have diagnosed and treated schizophrenia for over a century but have not come very far in alleviating its burden. This may be due to a simple, but essential aspect, widely ignored in conventional diagnostics, treatment and research: the moving body. The phenomenology-based embodiment approach to psychopathology regards schizophrenia as a prereflective disturbance of the embodied self, a disembodiment, which manifests in altered motor as well as interactional behavior. Although altered motor behavior has already been described in the 19th century and is considered an important domain of schizophrenia psychopathology today, the embodiment approach has not resulted in a fundamental change of research methods and diagnostics: There is no clear definition of a motor domain in schizophrenia; Motor abnormalities are not observed and indicated in the standard setting of clinical care; Widely used assessment scales, such as the Positive and Negative Symptom Scale (PANSS) include motor symptoms in a very imprecise and highly subjective way and very few of the assessment tools examine full-body movement.

Methods: In order to find empirical evidence for the theoretical concept of disembodiment and to explore ways of integrating movement into the diagnosis and treatment of schizophrenia, I propose an innovative experimental set-up: (1) Full-body Motion Tracking (MoCap) will be used to define socio-motor markers of schizophrenia. I will invite at least 40 participants (20 SCHZ, 20 CTRL) to the Heidelberg Center for Motion Research (HCMR). Eight MoCap cameras (Qualisys, space accuracy 1 mm, temporal resolution 120 Hz) will capture 48 markers attached to the participant’s skin and cloths while walking back and forth on a predefined path (A. simple walk, B. dual task: walk with cognitive task) and while doing coordination and interaction tasks (Tandem Walk, Star Jump, Mirror Game). The data-driven analysis of the resulting time series will follow algorithms by Troje and Tschacher. One-factorial ANCOVAs will shed light on differences between the groups. Movement characteristics will be related to symptom severity (NSS, PANSS) and self-experience, specifically body experience (EASE), of patients. In combination with a systematic literature review on descriptions of motor symptoms in different academic disciplines I will attempt the definition of a motor domain of the schizophrenic illness.