The Younger the Better? Variability in Language Development of Young German-speaking Children with Cochlear Implants

The influence of age at implantation and experiential factors on language development in young children with cochlear implants was examined. There were two samples, one cross-sectional with 41 children, and one longitudinal with 26 children. Age at implantation in both samples ranged from 6 to 47 months, with children evenly distributed in the age groups: 6-12, 13-24, 25-42 months at implantation. Linguistic progress was assessed by parental questionnaire, and for the longitudinal sample additionally, by one-hourly spontaneous speech samples. Data were collected 12, 18, 24 and 30 months after implantation. Measures of vocabulary and grammar were taken, including number of word types, MLU, inflectional morphology and sentence complexity. In both samples there was extensive variability in linguistic progress. Children’s linguistic progress was significantly related to social class, measured by parental education, but not age at implantation. Maternal dialogue variables were analyzed in the longitudinal sample and found to be related to children’s linguistic progress. Thus, experiential factors account for the extensive variability in children’s linguistic growth rather than age at implantation. The data support an epigenetic rather than a maturational concept of ‘sensitive phase’.