Experience-driven Predictability Does Not Influence Neural Entrainment to the Beat.

Humans spontaneously synchronize movements to a perceived underlying pulse, or beat, in music. Beat perception may be indexed by the synchronization of neural oscillations to the beat, marked by increases in EEG amplitude at the beat frequency [Nozaradan, S., Peretz, I., Missal, M., & Mouraux, A. Tagging the neuronal entrainment to beat and meter. Journal of Neuroscience, 31, 10234-10240, 2011]. Indeed, neural synchronization to the beat appears stronger for strong-beat than non-beat rhythms [Tal, I., Large, E. W., Rabinovitch, E., Wei, Y., Schroeder, C. E., Poeppel, D., et al. Neural entrainment to the beat: The "missing-pulse" phenomenon. The Journal of Neuroscience, 37, 6331-6341, 2017] and may underlie the generation of an internal representation of beat. However, because we are exposed disproportionately to strong-beat rhythms (e.g., most Western music) in the environment, comparisons of neural responses to strong-beat and non-beat rhythms may be confounded by relative differences in familiarity. Here, we dissociated beat-related and familiarity-related neural responses by comparing EEG amplitudes during the perception of strong-beat and non-beat rhythms that were either novel or made familiar through training. First, we recorded EEG from participants while they listened to a set of strong-beat, weak-beat, and non-beat rhythms. Then, they were trained on half of the rhythms over four behavioral sessions by listening to and tapping along with them, such that half of the rhythms were familiar by the end of training. Finally, EEG responses to the full rhythm set (half now familiar, half still unfamiliar) were recorded posttraining. Results show no effect of training on EEG amplitude at beat or stimulus-related frequencies and little evidence of familiarity-driven changes in EEG amplitude for weak- and non-beat rhythms. This suggests that oscillatory entrainment to the beat is not driven by familiarity and therefore likely reflects beat processing.