When 22 acupuncture clinicians and 23 patients seeking pain relief mirrored each other's facial expressions during acupuncture treatment, patients experienced less pain, according to a new study. Additionally, brain activity involved in representing the mental state of others, which is key for empathy and compassion, became more aligned after the doctor and patient had bonded during a clinical interaction prior to the treatment. Stronger alignment between these brain circuits was associated with stronger pain relief during treatment. The findings may help scientists better understand the neuroscience behind nonverbal patient-clinician interactions to improve clinical care. Positive clinical encounters are associated with higher patient satisfaction, mutual trust, treatment adherence, and clinical outcomes, while suboptimal interactions can result in miscommunication, clinician burnout, patient distrust, and decreased likelihood that patients will seek care. However, the behavioral and neural mechanisms behind these interactions have remained unknown. To investigate, Dan-Mikael Ellingsen and colleagues paired female patients suffering from chronic fibromyalgia pain with acupuncture clinicians. Pairs were assessed under two conditions - the doctor either first performed a consultation and intake with the patient to establish rapport before the treatment, or no such meeting occurred. For each treatment, the doctor prepared acupuncture needles attached to MRI-compatible electrodes hooked to an electronic needle stimulation device, then walked to an MRI scanner a short distance away, where they could communicate nonverbally with patients via video. Pairs that had established a clinical relationship beforehand - but not those who had just met - showed extensive alignment in brain circuitry involved in social mirroring during the treatment. Ellingsen et al. suggest that positive clinical rapport may provide a safety signal to patients, helping to drown out the pain and provide relief.