Revisiting the association between musical expertise and second-language proficiency

Musical expertise is frequently correlated with second-language (L2) proficiency, but it remains unclear whether this association generalizes across languages and measures. Here, we examined links between musical expertise and L2 proficiency among native speakers of Portuguese (Study 1) and Polish (Study 2). L2 (English) proficiency was assessed with both self-reports and objective tests of pragmatic competence. Musical expertise was defined as music training and musical ability, with ability assessed via self-reports and objective tests of melody and rhythm perception. In Study 1 (Portugal, n = 146), musical expertise showed no associations with L2 proficiency. In Study 2 (Poland, n = 174), after accounting for demographic variables and non-verbal reasoning, L2 proficiency correlated positively with self-reported musical ability, but not with music training or melody or rhythm perception. These findings suggest that links between musical expertise and L2 proficiency are weak, inconsistent, or contingent on how L2 proficiency is defined and measured.