Orthographic and cognitive factors in the concurrent development of basic reading skills in two languages

There is some controversy in the research literature as to whether the development of reading skills in different orthographies varies primarily as a function of common underlying cognitive processes ('the central processing hypothesis'), or alternatively, as a function of orthographic transparency ('the script dependent hypothesis'). These alternative views were examined by studying the reading skills of 245 children in grades 1-5, learning to read concurrently in English, their first language (L1) and Hebrew, their second language (L2). Children were administered a non-verbal intelligence task, parallel L1 and L2 memory tasks, and word recognition and pseudoword reading tasks in both languages. Ratings of Hebrew oral proficiency were provided by teachers. The central processing hypothesis was partially supported in that regardless of orthography, memory explained a small proportion of the variance on L1 and L2 reading measures. Though L2 oral proficiency was a significant predictor of L2 reading, it explained only a small proportion of the variance. The script dependent hypothesis was supported by the fact that (a) children could read more accurately voweled Hebrew (a 'transparent' orthography) than English (a 'deep' orthography), (b) the developmental profiles associated with English word recognition and pseudoword decoding was much steeper than the one depicting Hebrew word recognition and Hebrew pseudoword word decoding, and (c) decoding error categories were orthography-specific. We conclude that the two alternatives are complementary: When the script is less complex young children appear to develop their word recognition skills with relative ease, even in the absence of sufficient linguistic proficiency. At the same time, a more accurate picture of what facilitates L1 and L2 reading development is enhanced when individual differences in underlying cognitive skills are considered as well.