Nonverbal synchrony in diagnostic interviews of individuals with social anxiety disorder.

The present study examined nonverbal synchrony (i.e., synchrony between individuals' movement) during diagnostic interviews of individuals with and without social anxiety disorder (SAD). Specifically, 42 individuals with SAD and 42 individuals without SAD underwent a structured clinical interview, and videos of clinical interviews were analysed using Motion Energy Analysis (an objective machine-based video analysis) to quantify each individuals' movement as well as dyadic synchrony. Results indicated that interviews of individuals with SAD had significantly lower levels of nonverbal synchrony compared to interviews of individuals without SAD. In addition, interviews of individuals with SAD had lower levels of pacing compared to interviews of individuals without SAD (pacing refers to synchrony in which the interviewer initiates movement to which the participant responds). Analyses with social anxiety represented as a continuum of severity (vs. a diagnostic dichotomy) resulted in similar findings. Thus, individuals with SAD synchronized with interviewers' movement to a lesser extent compared to individuals without SAD, and social anxiety was associated with diminished synchrony. Implications for psychopathology and diagnosis of SAD are discussed.