Auditory and verbal memory predictors of spoken language skills in children with cochlear implants

Large variability in individual spoken language outcomes remains a persistent finding in the group of children with cochlear implants (CIs), particularly in their grammatical development.

In the present study, we examined the extent of delay in lexical and morphosyntactic spoken language levels of children with CIs as compared to those of a normative sample of age-matched children with normal hearing. Furthermore, the predictive value of auditory and verbal memory factors in the spoken language performance of implanted children was analyzed.

Thirty-nine profoundly deaf children with CIs were assessed using a test battery including measures of lexical, grammatical, auditory and verbal memory tests. Furthermore, child-related demographic characteristics were taken into account.

The majority of the children with CIs did not reach age-equivalent lexical and morphosyntactic language skills. Multiple linear regression analyses revealed that lexical spoken language performance in children with CIs was best predicted by age at testing, phoneme perception, and auditory word closure. The morphosyntactic language outcomes of the CI group were best predicted by lexicon, auditory word closure, and auditory memory for words.

Qualitatively good speech perception skills appear to be crucial for lexical and grammatical development in children with CIs. Furthermore, strongly developed vocabulary skills and verbal memory abilities predict morphosyntactic language skills.