Brain-Body Coupling in Listening to Metronomic Sounds and Music.

Wearables continue to expand their ability to sample more signals from the brain and body while reducing form factors and limiting on-device computing to meet real-world comfort and power constraints. Where evolving multimodal sensing platforms can combine electrophysiological (ExG), optical, chemical, and mechanical sensors for holistic brain-body state estimation, understanding of cross-modal coupling mechanisms remains limited. Here, we collect and analyze bio-signals in a brain-body coupling experiment using simultaneous electroencephalogram (EEG), electrocardiogram (ECG), and respiratory measurements. Our experimental paradigm contrasted listening to self-selected music, preceded by tempo-matched isochronous cues. The results show a clear entrainment of cardiac rhythms with the underlying beat of auditory stimuli for both metronome cues and subject-selected music. Magnitude-Squared coherence analysis showed frequency coupling across recorded modalities, with ECG, EEG, and breath, exhibiting peak coherence near heard or underlying musical beat or its harmonics. We present minimally pre-processed data to motivate future methodological explorations of multiscale brain-body entrainment to rhythmic stimuli.Clinical relevance-These findings have implications for designing music therapy and biofeedback interventions that could adapt to ongoing brain-body rhythms. Understanding brain-body entrainment mechanisms and validating simplified measurement approaches could enable more accessible and effective rhythmic interventions in clinical settings, particularly for conditions benefiting from audio-based therapies or cardiac rehabilitation.