Inter-Brain Synchrony as a Neural Mechanism of Social Connection in Schizophrenia

/ABSTRACT Social dysfunction is a core feature of schizophrenia, and individuals with a schizophrenia diagnosis often lack strong social ties to friends and family. This type of social disconnection is detrimental to health and associated with reduced quality of life. However, current treatments have little to no effect on social functioning and connectedness in schizophrenia, and new treatment approaches are urgently needed. Yet, poor understanding of the neural mechanisms that underlie the formation and maintenance of social connections in schizophrenia has hindered the development of novel interventions. Recent social neuroscience research has identified inter- brain synchrony as an important neural mechanism that promotes the formation of social ties by facilitating successful social interactions in healthy samples. Converging evidence suggests that this mechanism may be disrupted in schizophrenia, yet it has never been investigated directly in a schizophrenia sample. This project will investigate inter-brain synchrony and its relevance to social connection in schizophrenia for the first time, using methods adapted from non-clinical research. In this study, participants who have a schizophrenia diagnosis and healthy control participants will each take part in structured social interactions with two different laboratory confederates while electroencephalographic (EEG) recordings are collected simultaneously from both the participant and the confederate. The interaction with one confederate will include a conversation structured to induce a feeling of interpersonal closeness (experimental condition), while the interaction with the other confederate will include a conversation structured to include only superficial small-talk (control condition). The amount of inter-brain synchrony between participants and confederates will be assessed based on EEG activity from just before and after each conversation, during a brief collaborative task. This study has two major goals. First, the project will investigate inter-brain synchrony as a neural mechanism of social dysfunction in schizophrenia by comparing synchrony between the schizophrenia and control samples as well as investigating relationships between levels of inter-brain synchrony and participants’ social connectedness. Second, the project will test the malleability of inter-brain synchrony measures by comparing synchrony between the two experimental conditions and the pre- vs. post-conversation measures. As an additional goal, the project will investigate relationships between inter-brain synchrony and interpersonal synchrony of behavior measured during the social interactions, and with clinical variables (e.g., symptoms). Achieving these goals has the potential to transform the understanding and treatment of social dysfunction and disconnectedness in schizophrenia by elucidating the role of a novel neural mechanism. This study could offer new treatment targets for interventions to improve social functioning, and it could provide a basis for the development of novel biomarkers to assess social functioning in schizophrenia and other mental health conditions. Project Number: 1R21MH139044-01A1 | Fiscal Year: 2025 | NIH Institute/Center: National Institute of Mental Health (NIMH) | Principal Investigator: Eric Reavis (+1 co-PI) | Institution: UNIVERSITY OF CALIFORNIA LOS ANGELES, LOS ANGELES, CA | Award Amount: $433,125 | Activity Code: R21 | Study Section: Adult Lifespan Psychopathology Study Section[ALP] View on NIH RePORTER: https://reporter.nih.gov/project-details/11234188