Speech Functional Memory And Functional Features Of Visual Working Memory In Children With Chinese Reading Disabilities

The model of working memory theory, which was proposed by Baddeley and Hitch, is dominant in the field of reading disabilities. Working memory here refers to a limited capacity allowing the temporary storage and manipulation of the information. There are four components in the working memory, they are Phonological Loop (Verbal Working Memory), Visuo-spatial Sketch Pad (Visuo-spatial Working Memory), Central Executive and the Episodic Buffer.Phonetic writing has high transparency, which means it has strong form-sound corresponding rules. Researches from phonetic writing are consistently conclude that reading disabilities defect in verbal working memory, but there are no consistent conclusions about visuo-spatial working memory. Chinese characters are a kind of ideographic writing, combined form, sound and meaning together. Unlike phonetic writing, because of its low transparency, ideographic writing does not have strong form-sound-meaning corresponding rules, the readers need more visual spatial perceptual ability. There are about80percent to90percent of Chinese characters are phonograms, the retrieval of the phonetic element from Chinese characters relate to phonological processing. So whether there are verbal working memory or/and visuo-spatial working memory defects among Chinese reading disabilities. Both verbal working memory and visuo-spatial working memory are not single resources as a whole, they are made up of different components. The sub-components of the verbal working memory are phonological store and articulatory rehearsal, while visuo-spatial working memory is composed by visual object working memory and visual spatial working memory. This study based on the theory of Baddeley working memory model, aim at researching the functions and characteristics of the visual working memory and visuo-spatial working memory. Three experiments were carried out:Experiment1using visual rhyme task, compares whether there is a difference between Chinese dyslexia children and normal children in starting articulatory rehearsal mechanism, to investigate the functions and characteristics of the Chinese dyslexia in verbal working memory. With accuracy and reaction time as index, the results show that the group of Chinese dyslexia is significantly slower than the normal group in both the staring and non-starting retelling tasks, and they have longer reaction time. Although the reaction time decreased, but what’s the more important is that the dyslexia group has lower accuracy in starting rehearsal task than non-starting rehearsal task. This result suggests that Chinese reading disabilities defect the verbal working memory, especially the articulatory rehearsal mechanism.Experiment2using visual graphics memory task, compares whether there is a difference between Chinese dyslexia children and normal children in visual object working memory, to examine the functions and characteristics of the Chinese dyslexia in visual object working memory. The research found that the score of the reading disabilities are significantly lower than the normal children. So we think Chinese reading disabilities defect of the visual object working memory.Experiment3uses Grossi breadth paradigm, compares whether there is a difference between Chinese dyslexia children and normal children in visual spatial working memory, to explore the functions and characteristics of the reading disabilities in visual spatial working memory. The study found that dyslexia children’s visual spatial working memory score was significantly lower than normal group of children, so we think that Chinese dyslexia children defect of the visual spatial working memory.