Poster C9, Wednesday, August 21, 2019, 10:45 am – 12:30 pm, Restaurant Hall
Coarse print tuning in Chinese children with and without dyslexia: preliminary results from an EEG study
Urs Maurer1, Fang Wang1, Ka Chun Wu1, Jianhong Mo1, Xiao Chang Zheng1, Jie Wang2, Chin Lung Yang1, Catherine McBride1, Carrey T. S. Siu2, Kevin K. H. Chung2, Patrick C. M. Wong1;1The Chinese University of Hong Kong, 2Education University of Hong Kong
Coarse print tuning occurs within the first 200 ms after stimulus presentation, as measured by a difference in the N1 component of the ERP between responses to familiar words and unfamiliar visual control stimuli, such as symbols or false fonts. Coarse print tuning has been suggested to reflect visual expertise for words or letter strings. In alphabetic languages, N1 print tuning has been shown to develop with learning to read and to be reduced in children with dyslexia. The questions for the present study were whether print tuning would occur for Chinese in young children and whether it would be reduced in Chinese dyslexia. Here we report data from a preliminary sample of Chinese 2nd and 3rd graders who were either dyslexic (N=53) or not (N=29). They were presented with familiar Chinese and unfamiliar Korean characters, while the EEG was recorded. ERP analyses focused on the N1 component at left and right occipito-temporal (OT) electrodes. We additionally computed a topographic analysis of variance (TANOVA) at each time point to test for effects that were not restricted to the N1 component and OT electrodes. Even though the N1 itself was rather small, the repeated measures ANOVA on N1 amplitudes at OT electrodes revealed a robust main effect of stimulus condition (p<0.001), reflecting a larger N1 in response to Chinese compared to Korean. No other main effects nor any interactions were significant. The point-to-point TANOVA revealed significant ERP map differences between Chinese and Korean characters starting from 150 ms on, but no interaction between stimulus condition and group in any time window that was long enough to survive a duration correction for multiple comparisons. The robust effects of print tuning in the N1 component are in agreement with many previous studies in alphabetic languages and a few studies in Chinese, suggesting that print tuning also occurs in Chinese, presumably reflecting visual expertise. The lack of group differences in print tuning between dyslexic children and controls suggests that print tuning may play a different role for the development of dyslexia in Chinese compared to alphabetic languages.
Themes: Disorders: Developmental, Reading
Method: Electrophysiology (MEG/EEG/ECOG)