THE IMPACT OF MUSICAL FAMILIARITY ON TONAL SENSITIVITY: A BEHAVIOURAL AND ELECTROPHYSIOLOGICAL STUDY

Musical familiarity is thought to scaffold tonal prediction, yet its impact on neural indices of melodic discrimination remains unclear. Here we combined an ecologically valid tonal discrimination paradigm with high-density EEG to test how familiarity and musical exposure shape tonal sensitivity. Thirty right-handed adults listened to short trumpet renditions of familiar and unfamiliar melodies containing ±2-semitone deviations and performed a same–different judgment while P300, FN400 and Late Positivity (LP) components were recorded; participants also completed the melodic subtests of the Montreal Battery of Evaluation of Amusia (MBEA). Accuracy in the EEG task correlated strongly with MBEA performance (r = .69, p <.001), allowing us to contrast good and poor discriminators who differed in musical exposure. Good discriminators were more accurate, yet overall slower, and showed a pronounced left-hand advantage for detecting incongruent melodies, consistent with right-hemisphere specialization for global melodic processing. Electrophysiologically, they exhibited larger, right-lateralized P300 amplitudes and stronger FN400 and LP modulations by both familiarity and tonal deviance. SwLORETA source reconstruction of FN400 difference waves revealed preferential engagement of a left fronto-temporal and right superior temporal network, together with cerebellar contributions, during processing of unfamiliar and deviant melodies, with weaker and spatially restricted activation in poor discriminators. These findings indicate that everyday musical exposure sharpens hemispheric asymmetries and fronto-temporal–cerebellar circuitry supporting tonal sensitivity, suggesting that low MBEA scores may partly reflect limited familiarity with stylistically impoverished stimuli rather than genuine amusic traits.