Abstract
The authors compared language ability and neuro-psychological cognition in two patients, one (Case A) with a cochlear implant (CI) since 2 years of age, and the other (Case B) with an implant since 6 years of age. The conclusions were: 1) Patient A had suitable or better abilities for chronological age (CA) in the phonological cognition of single-syllables and words, acquisition of vocabulary, and articulation, a higher I. Q. on the Tanaka-Binet Test, V. I. Q. on the WPPSI, and the reading ability in age of 5 years that was the time after 2 years 11 month since he had started wearing the cochlear implant CI. 2) Patient B had a 100% score for abilities in the phonological cognition of single-syllables and words, a suitable I. Q. on the Tanaka-Binet Test, and the reading ability for CA, but she was greatly retarded in acquisition of vocabulary, and articulation, and her V. I. Q. on the WPPSI in age of 7 years that was the time after 1 year since she started wearing the CI. 3) These findings suggested that CIs should be implanted in congenitally children by 2 years of age, when the brain is very pliable.
