Neural entrainment predicts the anticipatory P300 component during musical meter perception: An EEG study using dual-meter sound stimuli

Meter, the organization of beats into regular groupings, is a core element of music perception that arises from the interplay between the bottom-up processing of acoustic features and top-down attentional mechanisms. To disentangle this interplay, we previously developed dual-meter stimuli consisting of band-limited noise bursts that varied in center frequency and duration, with one feature following a triple-meter pattern and the other a quadruple-meter pattern. The perceived meter thus switches between the two by shifting attention from one acoustic feature to another, even when the physical stimulus remains identical. Using these stimuli, we investigated whether directing attention to specific acoustic features is associated with neural entrainment and anticipatory processing of the perceived metrical structure, and whether the former predicts the latter, by recording electroencephalogram (EEG) signals while isolating the effects of acoustic differences. We found that EEG spectral profiles shifted toward the metrical structure of the attended feature, and that the P300 component, an index of anticipatory processing, tended to be larger when the metrical structure was disrupted than when it remained intact, although both measures varied considerably across individuals. Critically, linear regression analysis revealed that participants whose neural entrainment more closely tracked the attended metrical structure exhibited significantly larger P300 responses to metrical violations. These findings suggest that attending to specific acoustic features links neural entrainment with anticipatory processing, which may underlie meter perception.