The Event-related Potential Study On The Working Memory Of The Deaf Children

Today，working memory is a hot area of interdisciplinary research in cognitiveneuroscience. In the Verbal working memory, phonological loop more responsible for voicestorage and retell processing, congenital hearing-impaired children due to the lack ofphonological loop, not be able to receive auditory information is bound to affect theprocessing of verbal information, there are differences in the nature of normal children,thevoice of their visual presentation materials registration and retell mechanisms within thelanguage. Function and brain mechanisms are normal people have a certain distinction. In thisstudy, the hearing impaired children and normal children, different processing mechanisms inverbal working memory, their behavior and the neural basis are significantly different.Corresponding verbal working memory and normal children, the study of hearing-impairedchildren in this working memory is defined as working memory for sign language. The studyof Sign language loop of deaf children working memory, help investigate thehearing-impaired children in the learning process method improved.The first, second and third section briefly describes the composition of the workingmemory, phonological loop processing mechanism of the verbal working memory; review ofprevious studies liking impaired people sign language loop processing characteristics, the signlanguage of hearing-impaired people working memory the concept, comparing the hearingimpaired population with normal visual representation of voice information processingdifferent, the basic method and the presence of the controversial issues and assumptions, andultimately raised the basic idea of the research.The fourth part of the thesis is divided into two experimental studies, First experimentalstudy of the digital memory span of deaf children and hearing children’s verbal workingmemory capacity differences, by comparing to listen impaired working memory span ofchildren sign language significantly less than the normal hearing children. Provides a basis tofurther explore the brain mechanisms of hearing-impaired children sign language workingmemory. Second experiment delayed response task, carried out research on verbal workingmemory ERP repetition and recognition time process by comparing the hearing-impairedchildren and normal children presented in writing Chinese characters stored ERP waveformand brain mapping reaction time and accuracy of the matching stage to draw the followingconclusions: Deaf children verbal working memory span is significantly less than the normal children.In the delayed P260component phase front of the scalp produces Chinese charactersdelayed response tasks, the average latency of hearing-impaired children than normal childrenshort, average amplitude than the normal children; differences in average latency of N2component of deaf children in the rear of the scalp and normal children was not significant,the average amplitude than that of normal children. In the matching stage Chinese charactersdelayed response tasks, deaf children’s reaction time was significantly shorter than that ofnormal children; the correct rate of deaf children is significantly less than the normal children.Deaf children and normal children in the whole process of Chinese characters in the delayedresponse task, activation of the cerebral area roughly the same, but in the delayed phase ofnormal children in the forehead and on both sides of the central activation degree is high,normal children in occipital area has obvious activation, and deaf children only in the topregion and central activation is obvious. Between150-300ms in the matching stage, the deafchildren, the prefrontal cortex, the left ventrolateral prefrontal cortex and parietal occipitalarea of central cortex activation was greater in normal children, middle prefrontal cortex andbilateral parieto-occipital areas greater activation. The delayed response task in the process ofthe hearing-impaired children, amplitude and latency are generally shorter, the topographicmap of deaf children most brain regions activated earlier, in the matching stage reaction timewas significantly shorter than normal children, fully shows that deaf children in the possibleuse of brain mechanisms of early processing Chinese characters remain, but in terms ofefficiency processing significantly worse than normal children.