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.

Priming effects were examined in 40 children (9 -15 years old) using functional magnetic resonance imaging (fMRI). An orthographic judgment task required participants to determine if two sequentially presented spoken words had the same spelling for the rime. Four lexical conditions were designed: similar orthography and phonology (O+P+), similar orthography but different phonology (O+P−), similar phonology but different orthography (O−P+), and different orthography and phonology (O−P−). In left superior temporal gyrus, there was lower activation for targets in O+P+ than for those in O−P− and higher accuracy was correlated with stronger activation across all lexical conditions. These results provide evidence for phonological priming in children and greater elaboration of phonological representations in higher skill children, respectively. In left fusiform gyrus, there was lower activation for targets in O+P+ and O+P− than for those in O−P−, suggesting that visual similarity resulted in orthographic priming even with only auditory input. In left middle temporal gyrus, there was lower activation for targets in O+P+ than all other lexical conditions, suggesting that converging orthographic and phonological information resulted in a weaker influence on semantic representations. In addition, higher reading skill was correlated with weaker activation in left middle temporal gyrus across all lexical conditions, suggesting that higher skill children rely to a lesser degree on semantics as a compensatory mechanism. Finally, conflict effects but not priming effects were observed in left inferior frontal gyrus, suggesting that this region is involved in resolving conflicting orthographic and phonological information but not in perceptual priming.