Delayed auditory experience results in past tense production difficulties and working memory deficits in children with cochlear implants: A comparison with children with developmental language disorder

• Published in: Neuropsychologia Vol. 196; p. 108817
• Main Authors: Delcenserie, A., Genesee, F., Champoux, F.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 15.04.2024
• Subjects: Atypical early language experiences; Child; Children with cochlear implants; Cochlear Implants; Humans; Infant, Newborn; Language; Language Development Disorders - etiology; Language Tests; Memory Disorders; Memory, Short-Term; Past tense verbs; Working memory; Children with cochlear implants; Atypical early language experiences; Past tense verbs; Working memory
• ISSN: 0028-3932; 1873-3514; 1873-3514
• DOI: 10.1016/j.neuropsychologia.2024.108817

Extent evidence has shown that morphosyntax is one of the most challenging linguistic areas for children with atypical early language experiences. Over the last couple of years, comparisons between deaf children with CIs and children with DLD have gained interest – as cases of atypical early language experiences, including, but not restricted to, delayed onset of exposure to language input and language-processing difficulties. Evidence suggests that the morphosyntactic difficulties experienced by deaf children with CIs and children with DLD are very similar in nature. However, the few studies that have directly compared both groups are inconclusive, with deaf children with CIs either performing significantly better or on par with children with DLD. These differences in findings can be attributed, in part at least, to a failure to implement essential methodological controls – even more so given that deaf children with CIs comprise a very diverse population. The goal of the present study was to directly compare the performance of deaf children with CIs to that of children with DLD on a morphosyntactic ability known to be particularly difficult for both groups. Specifically, the present study conducted a detailed examination of the past tense marking abilities of deaf children with CIs and children with DLD while controlling for factors specific to deaf children with CIs, for children's basic cognitive abilities as well as for children's age, sex assigned at birth, and SES. Past tense verbs are particularly relevant as they are used as a marker of developmental language disorder (DLD) in children learning French. Moreover, extent evidence shows that deaf children with CIs and children with DLD have important WM difficulties, but also that there is an association between auditory perception, processing abilities, and working memory (WM) abilities as well as with the acquisition of morphological features, including tense marking. Unfortunately, no study has examined the relation between the accurate production of past tense verbs and WM abilities in children with CIs and children with DLD learning French. Fifteen deaf children with CIs between 5 and 7 years of age were compared to 15 children with DLD and to 15 typically-developing monolingual controls (MON), matched on important variables, using a past tense elicitation task as well as measures of phonological and nonverbal WM abilities. The results confirm that the deaf children with CIs and the children with DLD both performed significantly lower than the MON controls on the past tense elicitation task – suggesting that difficulties with past tense verbs in French might not only be a marker of DLD but, instead, a correlate of atypical language acquisition. Of importance, the present study is the first to show that deaf children with CIs perform significantly lower than children with DLD on a past tense elicitation task – highlighting the importance of using methodological controls. As well, significant correlations were found between the performance of the deaf children with CIs and of the children with DLD on the past tense elicitation task and their phonological and nonverbal WM abilities. Taken together with previous studies conducted in the same populations, this represents another evidence suggesting that early atypical language experiences result in language and WM deficits, including morphosyntactic difficulties. •On a past tense elicitation task, the performance of deaf children with cochlear implants and of children with developmental language disorder learning French was significantly below that of the monolingual controls.•This is the first study to show that the performance of deaf children with cochlear implants is significantly worse than that of children with developmental language disorder on a past tense elicitation task.•The total score of deaf children with cochlear implants on the past tense elicitation task was positively and significantly correlated with their performance on measures of phonological and nonverbal working memory. This was not found for the other groups.•Taken together with previous studies conducted in the same population, these results suggest that total linguistic deprivation prior to implantation and delayed onset of exposure to auditory input results in language and working memory deficits in deaf children with CIs.