N170 sensitivity to orthographic and visual-spatial processing in Chinese L1 and L2 kindergartners.

Abstract

Visual-spatial and orthographic processing skills contribute to early stages of learning to read, particularly in a morphosyllabic writing system such as Chinese. In addition, the parietal-occipital N170 component is sensitive to different classes of visual stimuli, and suggestively associated with perceptual expertise developed through plastic changes in the visual system. This study examined the visual-spatial and orthographic sensitivity of the N170 in emergent readers of Chinese. Kindergarten children speaking Chinese as a fi rst language (L1) and as a second language (L2) identified question marks in a stream of stimuli presented whilst recording their electrophysiological responses. The nonattended stimuli varied in script (Chinese characters, Korean Hangul characters vs. Chinese random strokes). Chinese vocabulary and word reading, Cantonese morphological, phonological and lexical tone awareness, Chinese orthographic memories, basic visual skills, and copying skills were also assessed behaviourally. L1 children outperformed L2 children on all Chinese reading related and orthographic knowledge measures, but did not differ on any basic visual, hand-eye coordination and pure copying skills. At the N170 component, signifi cant scriptal effects showed a greater N170 for Chinese followed by Korean and random strokes, indicating that the kindergarten children could passively distinguish familiar Chinese characters from unfamiliar stimuli. The hemisphere-by-script interaction suggest that the right hemisphere may be engaged in coarse-grained visualspatial analysis as Chinese and Korean differed from random strokes, whilst the left hemisphere is engaged in fi ner-grained visual-spatial and orthographic analysis as children differentiated Chinese and Korean scripts. Moreover, given that no group differences between L1 and L2 Chinese speakers were found, the challenges emergent readers face during early stages of learning to read Chinese as a second language possibly do not arise from assumed greater visual-spatial or orthographic demands indexed by the N170.