Cochlear implantation at 12 months: Limitations and benefits for vocabulary production

The purpose of this investigation was to learn the degree to which cochlear implantation at 12 months of age could reduce gaps in performance between hearing age and chronological age - that is, whether infants with access to cochlear implants at 12 months of age would be 12 months delayed, or less, in vocabulary production one year later.

Baseline vocabulary production was measured by parent interview and direct observation approximately 4 months post cochlear implant (CI) activation, and again 12 months after CI activation using the MacArthur-Bates Communicative Development Inventory: Words and Sentences.

Infants produced few if any words shortly after CI activation. Word production increased significantly during the 12 months following CI activation but scores were still significantly below age-level expectations based on chronological age. Vocabulary scores were, however, significantly better than expected based on hearing age, or duration of implant use.

Word production was delayed at both time points; however, access to cochlear implants at 12 months of age decreased the size of anticipated delays one year later, narrowing the expected gap between hearing age and chronological age.