[The longitude study on the mental development of congenital hearing-impaired infants and toddlers]

To explore the effect of chronological age and acoustic device in cognitive development of congenital hearing-impaired infants and toddlers, and analyze the correlation of abilities in cognitive development with other factors.

Depending on chronological age (1 year old group and 2 years old group) and acoustic device (hearing aids and cochlear implantation), locomotor, personal-social, hearing and speech, hand and eye co-ordination, performance tests in Griffith Cognitive Development Scale were used to assess the cognitive development of 80 hearing-impaired infants and toddlers aged 0-2 years, including before intervention (0 month), after intervention (6, 12 months). Datas were analyzed by Repeated Measurements and Pearson Correlation Test.

During 1 year hearing intervention and rehabilitation, hearing and speech, performance and cognitive were extremely significant difference for each phase of early intervention (P < 0.01), the development of locomotor, personal-social, hand and eye co-ordination were no significant difference (P > 0.05). Personal-Social in 1 year old group with hearing impairment was much higher than 2 years old group P < 0.05). Hearing and speech in cochlear implanted group with hearing loss was much higher than hearing aids group. Cognitive development was positive correlation with various region development P < 0.01), and was negatively correlated with chronological age (P > 0.05).

Cognitive development is proportional to recovery time. The chronological age of early intervention obviously affect deaf children's cognitive development. The ability of hearing and speech in cochlear implanted children is superior to children with hearing aids in severe and profound hearing impaired children.