Sympathetic nervous system synchrony between participants of couple therapy

Synchrony, or the moment-by-moment coordination between people in social situations, has been connected with increased liking and rapport. However, this type of synchrony is an underexplored area with regard to autonomic nervous system activity. The purpose of this research was to study physiological synchrony between participants in couple therapy by focusing on the sympathetic nervous system (SNS), which reflects arousal and emotional reactions. The data comprised 12 couple therapy cases (24 clients, 10 therapists) participating in the Relational Mind in Events of Change in Multiactor Therapeutic Dialogues (2013-2016) research project. Electrodermal activity (EDA) and heart rate were recorded from the clients and therapists at the start and at the end of the therapy. The aim of the research was threefold: to study the physiological reactions and synchrony that can be observed between participants in couple therapy, to analyze whether the levels of EDA synchrony change throughout the therapy processes, and to assess whether the possible changes in EDA synchrony are related to the therapeutic alliance or the therapy outcome. The results showed that between the participants of couple therapy, significant SNS synchrony occurred, which was not due merely to chance or to the presence of similar features within the therapy sessions. At the start of the therapy, the couples had the lowest level of SNS synchrony, whereas the co-therapists had the highest synchrony. The only significant SNS changes observed were in the couples, whose mutual synchrony increased towards the end of the therapy. The changes in SNS synchrony between the couples, and between the clients and the therapists, mostly showed a positive relationship with the increasing alliance and with the clients’ better wellbeing – although one specific pattern of decreasing synchrony seemed to be beneficial. The results highlight the role of embodiment in human interaction, and assist in understanding the healing mechanisms of therapy