Hand movements that change during psychotherapy and their relation to therapeutic outcome: An analysis of individual and simultaneous movements.

Hands are, compared to other body parts, the body parts that display the most gestural movements during an interaction and their movement is sensitive to reveal anxiety states. However, psychotherapy research focuses on movement synchrony of different body parts to be an indicator of improved symptoms. The present study investigates symptoms in social anxiety disorder and considers both, individual and simultaneous hand movements. 56 video recordings of 28 patient-therapist dyads with patients with social anxiety at the beginning and in the end of psychotherapy were analyzed. Two independent blind certified raters analyzed the hand movement behavior using the NEUROGES® analysis system for nonverbal behavior concerning individual movement units and the simultaneous overlaps between the patients' and therapists' movement units. Simultaneous overlap change negatively correlated with symptoms (LSAS week eight-measurement, r = -.52; and week 15-measurement, r = -.52; BDI pre-measurement, r = -.54). The patients' right hand movement at the end of the psychotherapy correlated significantly with therapeutic alliance (HAQ post-measurement; r = .55). Hand movement behavior analysis should be considered in psychotherapy research in combination with movement synchrony as a measurement parameter related to therapeutic process and outcome. Enriching previous findings, this study indicates that simultaneous movement change is related to symptoms and therefore a process-sensitive parameter in psychotherapy.