The influence of orthographic depth on reading networks in simultaneous biliterate children

Children in bilingual societies often simultaneously acquire reading skills in distinct writing systems that vary in consistency of sound-letter mapping or orthographic depth. To investigate its effect on cortical reading networks in children, we performed functional imaging on 34 simultaneous Hindi-English biliterate children as they read word and nonword stimuli. In contrast to Hindi which is consistent and relies on phonological assembly for both stimuli, English is inconsistent which necessitates lexical retrieval for words, but phonological assembly for nonwords. While children recruited a shared reading network for both languages, factorial analysis revealed stimulus effects (word/nonword) in bilateral frontal, parietal and left angular regions. Subsequent analyses showed that the stimulus effect was significant in English, which has a deep orthography, in comparison to Hindi, which is transparent. Our results provide novel evidence that orthographic depth shapes cortical reading processes during development. (C) 2015 Elsevier Inc. All rights reserved.