Phase-coded oscillatory ordering promotes the separation of closely matched representations to optimize perceptual discrimination

Indeed, item-specific neuronal activity was found to cluster on different oscillatory phases. However, the consequences of this neural mechanism for perception are unknown.

Here, we investigated whether and how neuronal item separation through oscillatory clustering influences perceptual item separation. In an EEG experiment, participants categorized sounds parametrically varying in pitch, relative to an arbitrary pitch boundary. We found that pre-stimulus oscillatory phase, in the theta and alpha ranges, biased near-boundary sound categorization responses to one category or the other.