Functional MRI study about Chinese character radicals identification in school children / 中华行为医学与脑科学杂志

ABSTRACT

Objective To explore the specific brain regions involved in Chinese character radicals visualspatial processing,as well as to explore the relationship between visual-spatial identification and Chinese characters radicals identification.To provide an evidence for understanding the underlying neural mechanism of developmental dyslexic.Methods Twelve healthy Chinese fourth and fifth grade children(7 boys and 2 girls,aged from 10 to 11 years old)were chosen from a primary school in Guangzhou.The children were native Chinese speakers and right handed.The subjects participated in two fMRI experiments on a 3.0 T Siemens MR scanner.Two separate block-designed cognitive tasks were devised,one was figure directions judgement task and the other was Chinese characters radical identification task.A single-shot GE-EPI scan sequence were used for fMRI scans.The BOLD fMRI data were collected and were preprocessed and analyzed in SPM2.Results The subjects had longer reaction time during the two experiments tasks than in control states((879±127)ms vs(805±124)ms,P=0.029;(917±144)ms vs(750±101)ms,P＜0.01),and had same response accuracy in both tasks and control states((96±5)% vs(95±8)%,P=0.515;(89±10)% vs(96±6)%,P=0.130).In figure direction judgement experiment,activations were found in bilateral occipital,right superior parietal,right precuneus and right middle frontal cortices.However,different and more extensive regions including left superior parietal,left precuneus,left hippocampus,right thalamus,right caudate cortices and bilateral occipital cortices were involved in identifying the radicals of Chinese characters.Conclusion Right hemisphere was dominant in judging the figure direction,and left hemisphere is dominant in identifying radicals of Chinese characters.These fMRI results show light on underlying partial similar neurophysiological mechanism between judging figure directions and identifying Chinese character radicals.The visual-spatial ability may be essential for Chinese character radical identification.