The shared conceptual system and language processing in bilingual children: Findings from literacy assessment in Spanish and Náhuatl

Findings are reported from a series of literacy assessments in which four classes of bilingual 3rd and 5th grade students from an indigenous community in Central Mexico participated. Subjects who completed the battery of tests of reading and writing in Spanish and Náhuatl range from balanced bilinguals to Spanish-dominant speakers with at least receptive language proficiency in Náhuatl, the principal indigenous language of the region (Tlaxcala and Puebla states). Typically, in bilingual schools in Mexico, instruction is predominantly or exclusively in Spanish. In the case of the present study, virtually all literacy teaching is carried out in Spanish, thus presenting investigators with the unique opportunity to examine the application of literacy skills learned through one language to literacy tasks in another language that children understand, but in which they have not had the opportunity to practice reading and writing. Findings offer a different vantage point from which to conceptualize the models of linguistic interdependence, common underlying proficiency, and transfer, developed and elaborated upon by researchers in the field of bilingual education. In the study of bilingualism and second language learning it is necessary to specify more precisely which aspects of language competence and language use are interdependent and which aspects are separate; what precisely does interdependence refer to? What are the conditions under which knowledge and skills stored in a common underlying proficiency can be accessed, in particular under special circumstances of language contact (for example, those that involve indigenous languages)? And is transfer a useful concept for describing the various aspects of bilingual proficiency?