Growth in literacy, cognition, and working memory in English language learners

• We assess ELL children’s growth on measures of working memory and literacy.
• Executive and phonological components of WM were distinct within L1 and L2.
• A hierarchical linear model separated cross-sectional effects from growth effects.
• Growth in the executive component of WM was directly linked to growth in L2 literacy.

This cohort sequential study explored the components of working memory that underlie English reading and language acquisition in elementary school children whose first language is Spanish. To this end, children (N = 410) in Grades 1, 2, and 3 at Wave 1 were administered a battery of cognitive (short-term memory [STM], working memory [WM], rapid naming, phonological processing, and random letter and number generation), vocabulary, and reading measures in both Spanish and English. These same measures were administered 1 and 2 years later. The results showed that (a) a three-factor structure (phonological STM, visual–spatial WM, and verbal WM) captured the data within both language systems, (b) growth in both the executive and STM storage components was uniquely related to growth in second language (L2) reading and language acquisition, and (c) the contribution of growth in the executive component of WM to growth in L2 processing was independent of growth in storage, phonological knowledge, inhibition, and rapid naming speed. The results suggested that growth in the phonological storage system does not supersede growth of the executive component of WM as a major contributor to growth in children’s L2 reading and language.