Nonverbal Social Communication and Gesture Control in Schizophrenia

Abstract

Schizophrenia patients are severely impaired in nonverbal communication, including social perception and gesture production. However, the impact of nonverbal social perception on gestural behavior remains unknown, as is the contribution of negative symptoms, working memory, and abnormal motor behavior. Thus, the study tested whether poor nonverbal social perception was related to impaired gesture performance, gestural knowledge, or motor abnormalities. Forty-six patients with schizophrenia (80%), schizophreniform (15%), or schizoaffective disorder (5%) and 44 healthy controls matched for age, gender, and education were included. Participants completed 4 tasks on nonverbal communication including nonverbal social perception, gesture performance, gesture recognition, and tool use. In addition, they underwent comprehensive clinical and motor assessments. Patients presented impaired nonverbal communication in all tasks compared with controls. Furthermore, in contrast to controls, performance in patients was highly correlated between tasks, not explained by supramodal cognitive deficits such as working memory. Schizophrenia patients with impaired gesture performance also demonstrated poor nonverbal social perception, gestural knowledge, and tool use. Importantly, motor/frontal abnormalities negatively mediated the strong association between nonverbal social perception and gesture performance. The factors negative symptoms and antipsychotic dosage were unrelated to the nonverbal tasks. The study confirmed a generalized nonverbal communication deficit in schizophrenia. Specifically, the findings suggested that nonverbal social perception in schizophrenia has a relevant impact on gestural impairment beyond the negative influence of motor/frontal abnormalities.

Gesture Performance in First- and Multiple-Episode Patients with Schizophrenia Spectrum Disorders

“…In the light of these findings, it is likely that inefficient gesture performance may contribute to impaired social functioning and functional outcome. Given that poor social perception impaired gesture performance [17], poor gesture performance in first-episode patients may result from poor social cognition at the very onset of the disorder. In fact, deficits in social cognition were reported even before the actual onset of psychosis, for instance in adolescents at risk for psychosis [48], and may already substantially impact social functioning in first-episode patients.…”

“…In addition, it was shown that pantomiming meaningless gestures was particularly disturbed [15], which is associated with poor frontal lobe function [16]. Furthermore, disturbed nonverbal social perception is linked to poor gesture performance in schizophrenia [17]. …”

Systems Neuroscience of Psychosis: Mapping Schizophrenia Symptoms onto Brain Systems

“…fMRI studies suggest the existence of similar domain-specific long-range connections between specialized cortical regions and the limbic system, e.g., for emotional face processing, between the fusiform gyrus, the amygdala, and the orbitofrontal cortex [23, 24]. In the motor domain, the capacity to recognize nonverbal information such as hand gestures is strongly linked to the performance of hand gestures [25], suggesting a parallel organization with direct connections between brain areas of action perception and those of action planning [26]. The cortical connections of the motor system include areas of executive control and action planning (rostral to primary motor cortex) and parietal areas of action perception (see right panel of Fig.…”

“…Two studies noted an association of impaired gesture performance with frontal lobe dysfunction and motor abnormalities in schizophrenia [25, 126]. In addition, patients have problems interpreting the hand gestures of others correctly [129].…”

“…Furthermore, they tend to misperceive neutral gestures as threatening [37] and incidental movements as gestures [36]. We demonstrated a generalized deficit – such as in gesture performance, gesture knowledge, nonverbal perception, and tool use – in schizophrenia [25]. In contrast to controls, performance was correlated between the tasks assessing nonverbal social perception, gesture performance, gesture recognition, and tool use.…”