Sociophonetic Variation and Change in Heritage Languages: Lexical Effects in Heritage Italian Aspiration of Voiceless Stops

In a previous study on voiceless stop aspiration in Heritage Calabrian Italian spoken in Toronto, we found that the transmission of a sociophonetic variable differed from cross-generational phonetic variation induced by increased contact with the majority language. Universal phonetic factors and the social characteristics of the speakers appeared to influence contact-induced variation much more straightforwardly than the transmission of the sociophonetic variable. In the current study, we investigate further, examining possible alternative explanations related to the lexical distribution of the aspiration phenomena. We test two alternative hypotheses, the first one predicting that the diffusion of a majority language's phonetic feature is frequency-driven while change in a sociophonetic feature is not (or not that regularly across generations), and the second one predicting that sociophonetic aspiration decreases across generations by being progressively more dependent on the frequency of lexical items. Our results show that sociophonetic aspiration resists lexicalization and applies to both frequent and infrequent words even in the speech of third-generation speakers. By contrast, the progressive introduction of contact-induced phonetic change is led by high-frequency words. These findings add to the complexity of heritage language phonology by suggesting that the pronunciation features of a heritage language can follow different fates depending on their sociolinguistic roles.