Development of Phonological, Lexical, and Syntactic Abilities in Children With Cochlear Implants Across the Elementary Grades

Purpose: This study assessed phonological, lexical, and morphosyntactic abilities at 6th grade for a group of children previously tested at 2nd grade to address 4 questions: (a) Do children with cochlear implants (CIs) demonstrate deficits at 6th grade? (b) Are those deficits greater, the same, or lesser in magnitude than those observed at 2nd grade? (c) How do the measured skills relate to each other? and (d) How do treatment variables affect outcome measures? Participants: Sixty-two 6th graders (29 with normal hearing, 33 with CIs) participated, all of whom had their language assessed at 2nd grade. Method: Data are reported for 12 measures obtained at 6th grade, assessing phonological, lexical, and morphosyntactic abilities. Between-groups analyses were conducted on 6th-grade measures and the magnitude of observed effects compared with those observed at 2nd grade. Correlational analyses were performed among the measures at 6th grade. Cross-lagged analyses were performed on specific 2nd- and 6th-grade measures of phonological awareness, vocabulary, and literacy to assess factors promoting phonological and lexical development. Treatment effects of age of 1st CI, preimplant thresholds, and bimodal experience were evaluated. Results: Deficits remained fairly consistent in type and magnitude across elementary school. The largest deficits were found for phonological skills and the least for morphosyntactic skills, with lexical skills intermediate. Phonological and morphosyntactic skills were largely independent of each other; lexical skills were moderately related to phonological skills but not morphosyntactic skills. Literacy acquisition strongly promoted both phonological and lexical development. Of the treatment variables, only bimodal experience affected outcomes and did so positively. Conclusions: Congenital hearing loss puts children at continued risk of language deficits, especially for phonologically based skills. Two interventions that appear to ameliorate that risk are providing a period of bimodal stimulation and strong literacy instruction.