Discriminate Sound Ability Of Children With Visual Impairment Of Cognitive Research

Sound discrimination is the first stage for people in learning language. Both oral communication and written reading include this progress. Visual impaired children have sensitive hearing, for example big hearing memory and good hearing attention. But it has not been studies whether sound (pure tone, music and speech sound included) discrimination is better or worse in visual impaired children than in normal children. Therefor this research was designed to examine this issue by signal detection theory.The sound was classified into two categories according to the type of sound wave. One was pure tune, the other was compound tone which was made up of music and speech sound. Therefor three kinds of sound materials were presented to blind, weak sighted and normal children. After they discriminated the sound, the right rate of their answers, sensory discriminability and response bias of them were computed. Results were used two-factor ANOVA analysis (age * eye condition) to examine effects of age and eye condition on the developing progress of children's sound discrimination ability. In addition, children's performances on these three different sounds were compared.The results showed that blind children had more sensitive hearing on pure tone discrimination than normal children but there was no difference between blind, weak sighted and normal children on music and speech sound discrimination. It was caused by the different distinguishing way between pure tone and compound tone. When discriminate pure tone, people relied on sensation and when discriminate compound tone, people relied more on perception integration, hearing tactics and many other factors. The results also somewhat supported the viewpoint that if visual impaired children had no other defects, they had no difference with normal children. And age is the most important factor for children in developing sound discrimination ability. From the developing progress standpoint, the results of this experiment supported Developmental Compensation theory. In pure tone and speech sound discrimination, blind children of small age performed much worse than normal children did. This meant visual impairment would block the children's development temporarily. But with the education, training and children's efforts, their backward ability could be compensated and impaired children would catch up with normal children. Finally they would have no difference with normal children in sound discrimination.