Supplementary Material for: Gesture Performance in First- and Multiple-Episode Patients with Schizophrenia Spectrum Disorders

<b><i>Background/Aim:</i></b> Gesturing plays an important role in social behavior and social learning. Deficits are frequent in schizophrenia and may contribute to impaired social functioning. Information about deficits during the course of the disease and presence of severity and patterns of impairment in first-episode patients is missing. Hence, we aimed to investigate gesturing in first- compared to multiple-episode schizophrenia patients and healthy controls. <b><i>Methods:</i></b> In 14 first-episode patients, 14 multiple-episode patients and 16 healthy controls matched for age, gender and education, gesturing was assessed by the comprehensive Test of Upper Limb Apraxia. Performance in two domains of gesturing - imitation and pantomime - was recorded on video. Raters of gesture performance were blinded. <b><i>Results:</i></b> Patients with multiple episodes had severe gestural deficits. For almost all gesture categories, performance was worse in multiple- than in first-episode patients. First-episode patients demonstrated subtle deficits with a comparable pattern. <b><i>Conclusions:</i></b> Subjects with multiple psychotic episodes have severe deficits in gesturing, while only mild impairments were found in first-episode patients independent of age, gender, education and negative symptoms. The results indicate that gesturing is impaired at the onset of disease and likely to further deteriorate during its course.