Nonverbal communication in schizophrenia: A 3-D Analysis of patients’ social interactions

Abstract

Background: Schizophrenia is a severe mental illness affecting approximately 0.4% of the population. A core feature of schizophrenia is social dysfunction, however, the precise nature of patients’ social deficits remain unknown. During face-to-face interaction we use nonverbal cues to coordinate, regulate and manage conversation. Patients have difficulty perceiving nonverbal cues in social cognitive tests, but it is unclear if this difficulty persists in their social encounters. The aim of this thesis is to determine if patients’ social deficits are manifest in the nonverbal behaviour of their social interactions, specifically investigating; (1) interpersonal coordination between the head movements of interacting partners and (2) the head and hand movements of patients and their partners in the context of conversation role. The relationship between nonverbal behaviour and patients’ symptoms, social cognition, rapport and social outcomes will also be assessed. Methods: The experimental study involved twenty patient (1 patient, 2 healthy participants) and twenty control (3 healthy participants) three-way groups. Groups were motion captured while discussing a moral dilemma. Healthy participants were unaware a patient was present. Results: (1) interpersonal coordination was reduced in patients’ three-way interactions (2) patients displayed less head and hand movement, while their healthy participant partners displayed more. Increased patients’ negative symptoms intensified this pattern and were associated with reduced patient rapport. Patients spending more time actively involved in their three-way interactions had poorer social outcomes. Patients’ performance on social cognitive assessments showed no association with their nonverbal behaviour. Interpretation: Patients’ three-way interactions display atypical patterns of nonverbal behaviour. The presence of a patient changes the behaviour of the healthy participants they are interacting with; even when they are unaware a patient is present. Patients’ symptoms mediate the behaviour of patients and their partners, and influence patients’ rapport.