Note-by-note predictability modulates rhythm learning and its neural components.

Rhythm production requires the integration of perceptual predictions and performance monitoring mechanisms to adjust actions, yet the role of auditory prediction remains underexplored. To address this, electroencephalography was recorded from 70 non-musicians as they synchronized with and reproduced rhythms containing notes of varying predictability. Participants were split into three groups, each receiving different visual cues to aid rhythm perception. Behaviorally, higher asynchrony occurred with less predictable notes. However, participants who viewed rhythms as distances between lines showed improved timing. EEG revealed that the Error Negativity component seems to reflect prediction error, increasing only when errors were clear and expected. When perceptual predictability was low, Ne response was reduced. The Error Positivity component, however, was heightened by both performance errors and unpredictable stimuli, highlighting the salience of such events. Overall, predictability plays a key role in shaping the neural and behavioral mechanisms underlying rhythm production.