Development of brain networks involved in spoken word processing of Mandarin Chinese

Abstract

Developmental differences in phonological and orthographic processing of Chinese spoken words were examined in 9-year-olds, 11-year-olds and adults using functional magnetic resonance imaging (fMRI). Rhyming and spelling judgments were made to two-character words presented sequentially in the auditory modality. Developmental comparisons between adults and both groups of children combined showed that age-related changes in activation in visuo-orthographic regions depended on task. There were developmental increases in left inferior temporal gyrus and right inferior occipital gyrus in the spelling task, suggesting more extensive visuo-orthographic processing in a task that required access to these representations. Conversely, there were developmental decreases in activation in left fusiform gyrus and left middle occipital gyrus in the rhyming task, suggesting that the development of reading is marked by reduced involvement of orthography in a spoken language task that does not require access to these orthographic representations. Developmental decreases may arise from the existence of extensive homophony (auditory words that have multiple spellings) in Chinese. In addition, we found that 11-year-olds and adults showed similar activation in left superior temporal gyrus across tasks, with both groups showing greater activation than 9-year-olds. This pattern suggests early development of perceptual representations of phonology. In contrast, 11-year-olds and 9-year-olds showed similar activation in left inferior frontal gyrus across tasks, with both groups showing weaker activation than adults. This pattern suggests late development of controlled retrieval and selection of lexical representations. Altogether, this study suggests differential effects of character acquisition on development of components of the language network in Chinese as compared to previous reports on alphabetic languages.

Developmental differences in the influence of phonological similarity on spoken word processing in Mandarin Chinese

“…Importantly, this group-wise difference in processing onset mismatches suggests that top-down processing does not influence spoken word recognition in children to the same extent that it does in adults. This finding complements earlier work using fMRI showing that top-down modulation from prefrontal areas of the brain is weaker in children compared to adults during spoken word recognition tasks (Bitan et al, 2006; Bitan et al, 2009; Cao et al, 2011). However, there is another explanation for this difference between groups.…”

“…Nevertheless, we hypothesize that rhyme effects will be stronger in adults compared to children, as recent work using functional magnetic resonance imaging (fMRI) has shown that top-down modulation is weaker in children compared to adults during tasks of spoken word recognition (Bitan et al, 2006; Bitan, Cheon, Lu, Burman, & Booth, 2009). It could be the case that this effect is especially prominent in Mandarin (Cao et al, 2011). …”

Literacy effects on language and vision: Emergent effects from an amodal shared resource (ASR) computational model

“…There is already substantial empirical evidence within the literature to support such a position with Chinese literates who have not been exposed to an alphabetic writing system displaying reduced levels of phonological awareness (Cheung et al, 2001;Ho & Bryant, 1997;Huang & Hanley, 1995McBride-Chang et al, 2004;Read et al, 1986;Shu et al, 2008). Further, recent evidence from neuroimaging studies support the critical role of orthographic transparency in modulating effects of literacy on speech processing, with less involvement of associated orthographic processing regions observed in logographic literates compared to alphabetic literates when processing speech (Cao et al, 2011) and greater developmental changes in phonological processing regions as a consequence of literacy training in English over Chinese students (Brennan et al, 2013).…”

“…phonemes) it has been proposed that explicit training is necessary. Evidence in support of this position comes from observed similarities in processing between illiterates and logographic literates, for example Chinese literates, where there is little systematic correspondence between orthographic representations and the sequence of speech sounds that constitute their spoken form (Brennan, Cao, Pedroarena-Leal, McNorgan, & Booth, 2013;Cao et al, 2011;Cheung, Chen, Lai, Wong, & Hills, 2001;Ho & Bryant, 1997;Huang & Hanley, 1995McBride-Chang, Bialystok, Chong, & Li, 2004;Read, Yun-Fei, Hong-Yin, & Bao-Qing, 1986;Shu, Peng, & McBride-Chang, 2008). …”

Brain bases of morphological processing in young children

“…These regions are also typically active in young Chinese readers during phonological reading tasks (Cao et al, 2010, 2011; Brennan et al, 2012; Bolger et al, 2008; Siok et al, 2004, 2008), possibly due to children’s greater morphological processing when reading in Chinese (McBride-Chang et al, 2013). We hypothesized that English-speaking children (ages 6–12) should also exhibit significant activation in left ventral inferior (BA 47) and middle frontal (MFG BA 9) regions during an auditory morphology task.…”