LONGITUDINAL APPROACHES TO SPEECH DEVELOPMENT IN BILINGUAL FAMILIES: INPUT QUANTITY, QUALITY, AND HOME LANGUAGE PRACTICES

Аннотация

Research on bilingual language development in early childhood highlights the critical role of input both in quantity and quality. Longitudinal designs provide unique opportunities to trace how dual-language exposure shapes children’s speech trajectories across time. This article outlines key methodological priorities for longitudinal research in bilingual families, emphasizing precise quantitative measures of input such as number of words and frequency of dialogues, alongside qualitative parameters including parental responsiveness and the use of language across different activities (Place and Hoff, 2011). Comparative studies across diverse socio-economic and cultural contexts are necessary to determine the conditions under which home use of English (or another majority language) supports optimal bilingual outcomes. Rigorous evaluation of interventions, including parent training programs, should employ experimental or quasi-experimental designs to assess causal effects on children’s speech development. We conclude that while targeted and balanced incorporation of English at home can provide bilingual advantages, preserving rich interactions in the heritage language and ensuring high-quality input remain essential. Practical strategies for parents and practitioners are proposed to optimizebilingual speech development. Keywords: Bilingual development, Longitudinal design, Language input, Parental responsiveness, Home languagepractices