Abstract
Professionals working with prelingually, profoundly deaf children with cochlear implants must be able to give both qualitative and quantitative information regarding vocabulary acquisition and all areas of language development. The following investigation is an initial attempt to address this need. This single subject study evaluated a 4-year-old, prelingually, profoundly deaf child's acquisition of receptive and expressive spoken vocabulary in the first year of multichannel cochlear implant use. Three standardized assessments were utilized to evaluate these areas of langu age development. A prelingually deaf child, after 12 months of cochlear implant use can be described as having a 'hearing age' of 12 months. It was hypothesized that the subject of this study would be more likely to acquire vocabulary at a rate similar to that of a hearing-age control, rather than that of a chronological-age control. In order to test this hypothesis, comparisons were made with standardized data for nor mally-hearing children. It was found that this child acquired vocabulary at approximately twice the rate of a hearing age control.