Visual perception in acoustically deprived and normally hearing children

In the present study an attempt was made to establish if and to what extent auditory deprivation modifies the processes of visual analysis and synthesis. The study included 54 children aged 10-16 years with hearing impairment attending the School and Educational Center for Children with Hearing Impairment in Wrocław (group I) and 127 children with normal hearing acuity attending public schools (group II), forming a reference group. Hearing impairment in the children of group I was from 60 to 100 dB. In 9 of these children the hearing impairment was inherited, while in some others it was acquired and resulted from rubella during the mother's pregnancy (5 subjects) or a severe disease course in childhood, for instance cerebral meningitis (4 subjects) and otolaryngologic antibiotic therapy (7 subjects). In the remaining subjects the reason for auditory deprivation was unknown. Hearing impairment, apart from genetically conditioned causes, appeared in the first months or years of life. The general intellectual level of the examined children was similar to that of their control counterparts, which was confirmed by school psychologists during a routine examination. The examination was performed by means of two tests from the Nonverbal Score of the Wechsler Intelligence Scale for Children: Puzzles and Block Design. The children with a hearing deficit generally needed more time to perform the tasks than those with normal hearing. The investigated parameters of visual perception improved in correlation with age, but the dynamics of these changes were different in the two study groups.