Language acquisition in young German-speaking children with cochlear implants: individual differences and implications for conceptions of a 'sensitive phase'.

The acquisition of language was studied longitudinally in a sample of 22 German-speaking children with cochlear implants (mean implantation age 29 months) and a control group of 22 normally hearing children. Spontaneous speech samples were collected over 27-36 months, starting at the the one-word stage. Results indicate that grammatical progress as measured by mean length of utterance was slower for cochlear-implanted children. However, there were substantial individual differences in the cochlear-implanted group. While 10 cochlear-implanted children progressed at pace with normally hearing children, 12 cochlear-implanted children remained well behind. Cochlear-implanted children who showed fast progress at an early stage continued to make fast progress as time went on, and those who showed slow progress early on continued to progress slowly. Pre-operative hearing was a better predictor of subsequent linguistic growth than age at implantation. Increases in vocabulary were associated with grammatical progress in both groups. Copyright 2001 S. Karger AG, Basel