Content area
Full text
Research Notes
The author(s) declare no competing financial interests.
Introduction
Knowledge of phonological structure of a language develops early in life through natural exposure to spoken language in the home environment (Jusczyk, Friederici, Wessels, Svenkerud & Jusczyk, 1993). This not only mediates learning the sounds of a language, but also lays the foundation for development of 'phonological awareness' (PA). PA refers to the inherent awareness of sound structure of a language, which enables complex manipulations of speech sounds (Caravolas & Bruck, 1993; Chuang, Joshi & Dixon, 2011). An extensive body of work has shown that phonological awareness skills are also the key stepping stone to reading acquisition (Wagner & Torgesen, 1987; Wagner, Torgesen, Rashotte, Hecht, Barker, Burgess, Donahue & Garon, 1997; Harm & Seidenberg, 1999; Goswami, 2001). However, most research to date has focused on the role of PA in reading development and relatively less effort has been made to investigate the neural correlates underlying PA itself. Given the above, the primary objective of this report was to examine the neuroanatomical structures underlying PA in children.
The children tested in this study were bilingual biliterates. It is estimated that about two thirds of the world's children are bilingual (Crystal, 1997). In many biliterate environments, children are instructed simultaneously in two languages (Bialystok, Luk & Kwan, 2005). Further, in various instances like Chinese-English, Hindi-English for instance, they learn to read languages that belong to distinct writing systems. Since the writing system that a language uses affects children's acquisition of literacy, biliteracy would be dependent on the successful acquisition of phonological information of two languages.
Past neuroimaging studies have demonstrated that acquisition of novel phonologies in multilinguals is associated with changes in brain structure. One such study (Abutalebi, Rosa, Castro Gonzaga, Keim, Costa & Perani, 2013) specifically studied non-native language production in adult multilinguals and reported two important findings: (1) multilinguals exhibited increased activity in left putamen for non-native language, and (2) the same multilingual population also showed higher grey matter in the same region - left putamen, as compared to monolinguals. The study concluded that the observed grey matter changes were the result of expertise in articulating multiple phonologies. Such neuroanatomical effects are hitherto unexplored in bilingual children, where acquisition of two sets of phonologies takes...