Influential factors in lexical richness of young heritage speakers’ family language: Iranians in New Zealand

This study investigates the extent to which young heritage speakers’ oral narratives in their first language (L1) differ from monolinguals’ narratives with regard to lexical richness (lexical diversity and lexical sophistication). It also explores which demographic factors (age, age at emigration and length of emigration) and/or socio-linguistic factors (frequency of heritage language use and parental attitudes toward heritage language maintenance) account for the differences. The participants were a group of 25 young speakers of Persian as a heritage language, who were either born in or emigrated to New Zealand, and a group of 25 monolingual counterparts in Iran. Demographic information about the heritage speakers as well as information about parental attitude and practices regarding heritage language acquisition and maintenance were collected through semi-structured interviews with their parents. A film-retelling task was used to elicit the oral narratives, and these were analyzed for lexical diversity (by means of the Measure of Textual Lexical Diversity) and for lexical sophistication (by counting the incidence of low-frequency words). As expected, the monolinguals’ narratives tended to manifest greater lexical richness than the heritage speakers’, especially according to the measure of lexical sophistication. Against expectation, frequency of heritage language use and parental attitude toward heritage language acquisition and maintenance were not found to be significant predictors of the young heritage speakers’ results. For the heritage speakers who were born in New Zealand, the results were predicted best by their age, while for those who arrived in New Zealand at a later age, the best predictors were both their age and how old they were at the time of emigration. This suggests that the demographic factors overrode the potential influence of the socio-linguistic variables examined. This study sheds light on (factors that contribute to) young heritage speakers’ L1 lexical competence, a topic that has hitherto been under-investigated. A major implication of this study is showing the association of age and heritage speakers’ lexical richness. Although the statistical analyses did not show the effect of socio-linguistic variables, this finding indirectly supports the effect of parental input on heritage language proficiency in young bilinguals. Limitations of the study include the relatively small number of participants, the use of only one task to elicit speech samples and the reliance on parents’ self-reported family language habits