Home language and societal language skills in second-generation bilingual adults

Research aims were (a) to test competing predictions regarding the levels of heritage and societal language proficiency among young adults who experienced early exposure to both languages, and (b) to identify sources of individual differences in degree of bilingualism.

Participants comprised 65 Spanish-English bilinguals who reported using both languages on a weekly basis, 25 native English monolinguals, and 25 native Spanish monolinguals. Language and literacy skills were assessed with a battery of standardized and research-based assessments. Degree of bilingualism was calculated for the bilingual participants.

Paired sample t-tests compared the bilinguals' skills in English to their skills in Spanish. Hierarchical regression evaluated factors related to their degree of bilingualism. Independent sample t-tests compared bilinguals' single-language skills to monolinguals.

The bilinguals' English skills were stronger than their Spanish skills on every measure. Thus, degree of bilingualism was largely a function of level of Spanish skill and was associated with concurrent Spanish exposure. Bilinguals' English skills were not different from the monolinguals except in speed of lexical access. The bilinguals' Spanish skills were significantly lower than the Spanish monolinguals on every measure except in accuracy judgments for grammatically correct sentences.

Previous studies of bilingual adults have focused on sequential bilinguals and previous studies of heritage language speakers have focused on their grammatical skills. This is the first study, to our knowledge, to assess a wide range of functionally relevant skills in adults with early exposure to a heritage and societal language.

These findings demonstrate that early exposure to and continued use of a home language does not interfere with the achievement of societal language and literacy skills, while also demonstrating that even a widely and frequently used home language may not be acquired to the same skill level as a societal language used in school.