Augmented Patient-Clinician Interactions Enhance Inter-Brain Synchrony Between Scalp Regions – a Hyperscan EEG Study

The patient-clinician relationship is central in clinical therapies for chronic pain. Previous research has found that a warm and empathic (augmented) clinical interaction compared to a neutral, business-like (limited) interaction can improve clinical outcomes, though what brain mechanisms are involved is still unknown. We completed an EEG-hyperscanning study (N=34 dyads) with brain EEG signals collected from chronic low back pain patients and clinicians (acupuncturists) during an ecologically valid experimental setting. Patients experienced either an augmented or a limited style clinical intake followed by an evoked pain task with acupuncture treatment and no-treatment trials. Behavioral data showed that the quality of the patient-clinician interaction did not directly modulate pain analgesia. However, patients randomized to the augmented group compared to the limited group reported decreased negative affect and higher expectations and interest in future acupuncture therapy. The brain-to-brain analysis (validated pipeline from Schwartz, 2022) revealed a greater linkage in the Alpha and Beta bands between right temporal-central areas in the patient-clinician network following augmented-style interaction, with comparable interconnectivity between augmented and limited groups during pain treatment in the left hemisphere. Additionally, following augmented interaction, clinicians’ right frontal region was highly connected with all patients’ brain regions, particularly with the cross-hemispheric frontal area. This result suggests a unique role for clinicians’ right frontal area in sustaining inter-brain synchrony during pain treatment, confirming its known involvement in higher-order social functions, including recognition of social clues and mentalizing. Future analyses will evaluate the link between inter-brain connectivity and behavioral/clinical outcomes following therapy.