Manipulation of interpersonal synchrony in psychotherapy using extended reality: Mapping future directions.

Interpersonal synchrony is the dynamic coordination of two individuals over time, reflected in the alignment of their actions, emotions, thoughts, and physiological processes. Interpersonal synchrony is a core mechanism associated with therapeutic alliance and treatment outcomes in psychotherapy. However, given the largely correlational nature of current literature, manipulation of synchrony is essential in order to reveal its potential causal relationships with therapeutic relationships in psychotherapy. Despite growing recognition of its clinical significance, synchrony remains difficult to manipulate because it often emerges implicitly, shaped by relatively stable individual and interpersonal characteristics. This paper first introduces an Extended Reality (XR)-based framework for understanding interpersonal synchrony, drawing from Milgram and Kishino's Reality-Virtuality continuum. We then use this framework to map options for synchrony manipulation during therapeutic encounters involving real and digital entities. We then explore the different challenges of implementing these synchrony manipulations, including conceptual, technological, and ethical issues. This outlines a future-oriented perspective on the potential of XR to provide an infrastructure for synchrony manipulation. This may provide new opportunities for tailoring therapy to individual synchrony profiles, with potential applications in treating disorders marked by interpersonal dysfunction, such as social anxiety or autism spectrum disorder. Ultimately, XR manipulation of synchrony may transform both research and clinical practice by bridging the gap between static trait-like tendencies and the facilitation of adaptive therapeutic flexibility.