Beta bursts correlate with synchronization of movements to rhythmic sounds

Accumulating evidence indicates transient beta bursts play an important role in the representation of temporal information and prediction. However, the role of beta bursts in sensorimotor synchronization (SMS) involving active interactions between motor and sensory systems to synchronize predictive movements to periodic events remains unclear. To answer this question, 15 participants were invited to complete a finger-tapping task whilst high-density EEG (128 channels) was recorded. Participants tapped with their right index finger in synchrony with 1 Hz and 0.5 Hz tone trains. In line with previous findings, we found a negative mean asynchrony between tone and tap time, i.e., taps preceded tones for both tone frequencies (1 and 0.5 Hz). In the EEG data, beta bursts were detected and their timing in relationship with tapping and auditory tracking was examined. Results revealed that beta bursts tracked tapping and were modulated by the low frequency phase of the tone frequency (i.e., 1 Hz or 0.5 Hz). Importantly, the locking of beta bursts to the phase of auditory tracking correlated with the behavioural variance on a single trial level that occurred while tapping to the tones. These results demonstrate a critical role for an interplay between beta bursts and low frequency phase in coordinating rhythmic behaviour.