The Influence of Vocal Synchrony on Outcome and Attachment Anxiety/Avoidance in Treatments of Social Anxiety Disorder

• Published in: Psychotherapy (Chicago, Ill.) Ill.), 2021-12, Vol.58 (4), p.510-522
• Main Authors: Schoenherr, Désirée, Strauss, Bernhard, Stangier, Ulrich, Altmann, Uwe
• Format: Article
• Language: English
• Subjects: Anxiety; Anxiety Disorders - therapy; Attachment Behavior; Avoidance; Female; Human; Humans; Interpersonal Relationships; Male; Phobia, Social; Psychotherapy; Severity (Disorders); Social Phobia; Synchrony; Therapeutic Alliance; Treatment Outcome; Treatment Outcomes
• ISSN: 0033-3204; 1939-1536
• DOI: 10.1037/pst0000393

Research indicates an effect of nonverbal synchrony on the therapeutic relationship and patients' symptom severity within psychotherapy. However, vocal synchrony research is still rare and inconsistent. This study investigates the relationship between vocal synchrony and outcome/attachment dimensions, controlling for therapeutic alliance and movement synchrony. Our sample consisted of 64 patients with social anxiety disorder. Symptom severity was assessed with the Liebowitz Social Anxiety Scale and the Inventory of Interpersonal Problems, whereas attachment was assessed with the Experiences in Close Relationships Questionnaire at the beginning and end of therapy. Therapeutic alliance was measured with the Helping Alliance Questionnaire II. We determined vocal synchrony of the median and range of the fundamental frequency (f0) by correlating f0 values of manually segmented speaker turns. Movement synchrony was assessed via motion energy and time-series analyses. Patient- and therapist-led synchrony was differentiated. Statistical analyses were performed using mixed effects linear models. Vocal synchrony had a negative impact on outcome. Higher vocal synchrony led to higher symptom severity (if the patient led synchrony, at the end of therapy) as well as attachment anxiety, avoidance, and interpersonal problems at the end of therapy. Predicting attachment anxiety, the effect of therapist-led vocal synchrony went beyond the effect of therapeutic alliance and movement synchrony. High vocal synchrony may arise due to a lack of autonomy in social anxiety disorder patients or might reflect attempts to repair alliance ruptures. The results indicate that vocal synchrony and movement synchrony have different effects on treatment outcome. Clinical Impact Statement Question: This study investigated the association between vocal synchrony and symptom change and changes in attachment dimensions of patients with social anxiety disorder. Vocal synchrony was assessed using a highly standardized segmentation procedure and automated extraction of vocal features. Findings: Results show that high vocal synchrony was linked to higher symptom severity (social anxiety, avoidance, and interpersonal problems) and higher attachment anxiety and avoidance at the end of therapy. The effect of vocal synchrony on attachment anxiety goes beyond the effect of therapeutic alliance and movement synchrony. Meaning: This study highlights the differential effect of nonverbal synchrony, in parti