Effect of Early Intervention on Language Development in Hearing-Impaired Children

Hearing loss from birth up to the age of 3 years has a negative effect on speech/language development and results in sensory, cognitive, emotional, and academic defects in adulthood by causing delayed development of communicative-linguistic abilities. The present study was performed in order to assess the effect of early intervention on language development in Persian children aged 6-7 years with severe sensorineural hearing loss. Thirty boys and girls aged 6-7 years participated in this study, all of them had severe congenital sensorineural hearing loss in both ears. All children were using bilateral behind-the-ear hearing aid, and had similar economic/socio-cultural backgrounds. Subjects were categorized into two groups based on the age of identification/intervention of hearing loss (3-6 and 12-15 months of age). The Persian TOLD-P3 test was used to evaluate language development in all subjects. Data collection was accomplished by observation, completion of questionnaires, and speech recording. There was a significant difference in language development in 11 sub-tests and five lingual gains on the Persian TOLD-P3 test between early (3-6 months of age) and late identified/intervened (12-15 months of age) hearing-impaired children (P<0.05). Early identified/intervened hearing-impaired children had a notable preference in all assessed sub-tests and lingual gains. Early identification/intervention of hearing loss before the age of 6 months has a significant positive effect on a child’s language development in terms of picture/relational/oral vocabulary, grammatical comprehension, sentence combining, grammatical completion, phonologic analysis, word differentiation, word production, semantics, and syntax. Moreover, early identification/ intervention of hearing loss develops the hearing-impaired child’s lingual gains in visual vocabulary, grammatical completion, word differentiation, phonologic analysis, and word production.