Listeners can easily say if a singer sounds in tune or out of tune (Larrouy-Maestri et al., 2013, 2015) and if a band plays on the beat or not. In fact, we are used to “categorize” what we hear and identify performances sounding wrong. However, as is true for several types of judgments (e.g., beauty or obscenity), the definition of ‘correctness’ in music lacks precision, and the foundation of such categorization remains unclear (Larrouy-Maestri, under review). This project examines what ‘correctness’ means in different musical contexts and the cognitive processes behind such categorization. To do so, we investigate auditory processing of manipulated sequences with methods from psychophysics, physiology and electrophysiology. By comparing ‘correctness’ perception across pitch and time dimensions and examining potential listeners’ profiles, this project aims at clarifying the mechanisms underlying music perception.