The Role of the Temporoparietal Junction (TPJ) in the Patient/clinician Interaction During Evoked Pain Treatment - a Hyperscan EEG Study

The patient/clinician relationship is central in clinical therapies for chronic pain and has been linked with treatment efficacy. To assess the brain mechanisms underlying these psychosocial interactions, neurophysiological objective measures are still needed. A recent publication from our team applied functional MRI hyperscanning (synchronized neuroimaging) to demonstrate that patient/clinician brain concordance in the temporoparietal junction (TPJ) was up-regulated following a clinical interaction and this up-regulation was associated with analgesia in fibromyalgia patients. Here we propose a hyperscanning study where the patient/clinician brain response is evaluated using electroencephalography (EEG). This non-invasive neuroimaging technique allowed for an ecologically valid experimental setting with a realistic intervention as well as further characterization of TPJ dynamics in the brain-to-brain model during pain treatment. We recorded EEG simultaneously (28 dyads, 64 channels) from low-back pain patients and acupuncturists during a task with treatment and no-treatment trials in conjunction with evoked cuff pain. Using a liner-inverse approach, we reconstructed the electrical activity from 17 Regions of Interest. Statistical connectivity patterns were obtained by comparing Partial Directed Coherence estimated for treatment and no-treatment trials (α=0.05, FDR corrected) and their properties were summarized by computing the degree of each node (number of connections exchanged between brains involving a specific area). We found that TPJ was one of the dominant nodes connecting patient and clinician brain activity in Theta band. TPJ degree in the patients was significantly higher during treatment trials compared to no-treatment (p<0.01). Additionally, we found increased connectivity in clinicians’ TPJ when evoked pain was being observed, but not treated. The key role of the TPJ in the patient/clinician interaction during pain treatment has now been demonstrated by both EEG and fMRI neuroimaging. Future studies will investigate how TPJ activity and concordance can predict]the quality of the patient/clinician interaction and clinical outcomes for a longitudinal treatment. Grant support from R33-AT009306. The patient/clinician relationship is central in clinical therapies for chronic pain and has been linked with treatment efficacy. To assess the brain mechanisms underlying these psychosocial interactions, neurophysiological objective measures are still needed. A recent publication from our team applied functional MRI hyperscanning (synchronized neuroimaging) to demonstrate that patient/clinician brain concordance in the temporoparietal junction (TPJ) was up-regulated following a clinical interaction and this up-regulation was associated with analgesia in fibromyalgia patients. Here we propose a hyperscanning study where the patient/clinician brain response is evaluated using electroencephalography (EEG). This non-invasive neuroimaging technique allowed for an ecologically valid experimental setting with a realistic intervention as well as further characterization of TPJ dynamics in the brain-to-brain model during pain treatment. We recorded EEG simultaneously (28 dyads, 64 channels) from low-back pain patients and acupuncturists during a task with treatment and no-treatment trials in conjunction with evoked cuff pain. Using a liner-inverse approach, we reconstructed the electrical activity from 17 Regions of Interest. Statistical connectivity patterns were obtained by comparing Partial Directed Coherence estimated for treatment and no-treatment trials (α=0.05, FDR corrected) and their properties were summarized by computing the degree of each node (number of connections exchanged between brains involving a specific area). We found that TPJ was one of the dominant nodes connecting patient and clinician brain activity in Theta band. TPJ degree in the patients was significantly higher during treatment trials compared to no-treatment (p<0.01). Additionally, we found increased connectivity in clinicians’ TPJ when evoked pain was being observed, but not treated. The key role of the TPJ in the patient/clinician interaction during pain treatment has now been demonstrated by both EEG and fMRI neuroimaging. Future studies will investigate how TPJ activity and concordance can predict]the quality of the patient/clinician interaction and clinical outcomes for a longitudinal treatment. Grant support from R33-AT009306.