The Choreography of Coupled Brains: Coordinated Movement and Multi-Scale Neural Synchrony in Musical Theater for Individuals with Developmental Disabilities

Performing together, which demands moving, singing, and coordinating in real time, is among the most social things people do, yet whether such coordination synchronizes not only behavior but brain activity, within and between performers, has rarely been examined during genuine performance. In this pilot study, we used mobile electroencephalography, including dual-brain hyperscanning of co-performing partners, to resolve neural change over a 16-week musical-theater program in adolescents and adults with developmental disabilities, the majority autistic. We examined four levels: behavior, spectral power, within-brain (source-space) connectivity, and between-brain synchrony, framing all estimates as effect sizes. Anxiety decreased from pre- to post-intervention, consistently across participant and parent reports. During performance, high-beta and gamma power and within-brain amplitude connectivity rose broadly across the cortex, with maximal effects seen in parieto-occipital regions. Between-brain coupling was similarly carried by amplitude co-fluctuation rather than phase; however, it was graded by the degree of interpersonal movement coordination (strongest when partners mirrored one another) and scaled with movement vigor. Local and within-brain changes were thus broad and state-like, whereas coupling between brains was specific to interpersonal coordination. Coordinated movement may organize neural synchrony across scales, positioning musical theater as a tractable model for studying the social brain in motion.