Grammatical Abilities in Young Cochlear Implant Recipients and Children With Normal Hearing Matched by Vocabulary Size

The Contribution of Noun and Verb Lexicon Sizes to Later Grammatical Outcomes in Mandarin-Speaking Children With Cochlear Implants

PURPOSE

The present study evaluated the applicability of the sentence-focused framework to Mandarin-speaking children with cochlear implants (CIs) by examining the relative contribution of receptive/expressive noun and verb lexicon sizes to later grammatical complexity.

METHOD

Participants were 51 Mandarin-speaking children who received cochlear implantation before 30 months of age. At 12 months after CI activation, parents were asked to endorse words that their child could understand only or understand and say using the infant version of the Early Vocabulary Inventory. At 24 months after CI activation, parents were asked to endorse the grammatical structures that their children were able to say using the Grammatical Complexity subtest in the Mandarin Communicative Development Inventory-Taiwan. Children's receptive/expressive noun and verb lexicon sizes and grammatical complexity scores were computed from these parent checklists.

RESULTS

Correlational analyses showed that children's receptive/expressive noun and verb lexicon sizes at 12 months after CI activation were all highly correlated with their grammatical complexity scores at 24 months after CI activation (ρs = .52-.63, ps < .001). Regression analyses further revealed that verb lexicon sizes at 12 months after CI activation outweighed noun lexicon sizes in accounting for grammatical complexity at 24 months after CI activation.

CONCLUSIONS

Our findings supported the prediction of the sentence-focused framework. Emphasizing the role of verbs in early intervention has the potential to enhance grammatical outcomes in Mandarin-speaking children with CIs.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.26129044.

Processing of Plural Marking in Nouns by German-Speaking Children With Normal Hearing and Children With Cochlear Implants: An Eye-Tracking Study

PURPOSE

Our goal is to understand how the different types of plural marking are understood and processed by children with cochlear implants (CIs): (a) how does salience affect the processing of plural marking, (b) how is this processing affected by the incomplete signal provided by the CIs, and (c) is it linked to individual factors such as chronological age, vocabulary development, and phonological working memory?

METHOD

Sixteen children with CIs and 30 age-matched children with normal hearing (NH) participated in an eye-tracking study. Their task was to choose the corresponding picture to an auditorily presented singular or plural noun. Accuracy, reaction time, and gaze fixation were measured and analyzed with mixed-effect models.

RESULTS

Group differences were found in accuracy but not in reaction time or gaze fixation. Plural processing is qualitatively similar in children with CIs and children with NH, with more difficulties in processing plurals involving stem-vowel changes and less with those involving suffixes. Age effects indicate that processing abilities still evolve between 5 and 11 years, and processing is further linked to lexical development.

CONCLUSIONS

Our results indicate that early implantation seems to be beneficial for the acquisition of plural as indicated by very small between-group differences in processing and comprehension. Processing is furthermore affected by the type of material (i.e., phonetic, phonological, or morphological) used to mark plural and less so by their segmental salience. Our study emphasizes the need to take into account the form of the linguistic material in future investigations at higher levels of processing.

Learning a Sign Language Does Not Hinder Acquisition of a Spoken Language

PURPOSE

The purpose of this study is to determine whether and how learning American Sign Language (ASL) is associated with spoken English skills in a sample of ASL-English bilingual deaf and hard of hearing (DHH) children.

METHOD

This cross-sectional study of vocabulary size included 56 DHH children between 8 and 60 months of age who were learning both ASL and spoken English and had hearing parents. English and ASL vocabulary were independently assessed via parent report checklists.

RESULTS

ASL vocabulary size positively correlated with spoken English vocabulary size. Spoken English vocabulary sizes in the ASL-English bilingual DHH children in the present sample were comparable to those in previous reports of monolingual DHH children who were learning only English. ASL-English bilingual DHH children had total vocabularies (combining ASL and English) that were equivalent to same-age hearing monolingual children. Children with large ASL vocabularies were more likely to have spoken English vocabularies in the average range based on norms for hearing monolingual children.

CONCLUSIONS

Contrary to predictions often cited in the literature, acquisition of sign language does not harm spoken vocabulary acquisition. This retrospective, correlational study cannot determine whether there is a causal relationship between sign language and spoken language vocabulary acquisition, but if a causal relationship exists, the evidence here suggests that the effect would be positive. Bilingual DHH children have age-expected vocabularies when considering the entirety of their language skills. We found no evidence to support recommendations that families with DHH children avoid learning sign language. Rather, our findings show that children with early ASL exposure can develop age-appropriate vocabulary skills in both ASL and spoken English.

Deficient sensory and cognitive processing in children with cochlear implants: An event-related potential study

Compared with children having normal hearing (NH), those with cochlear implants (CIs) perform poorly in spoken language comprehension which involves both low-level acoustic encoding and higher-level cognitive processing. Here, we performed an electroencephalography study to portray this brain dynamics of speech perception in CI children. We presented a Mandarin Chinese monosyllable or four-syllable idiom to CI and NH children, and infrequently varied its lexical tone to form a novel monosyllable or pseudo-idiom in an oddball paradigm. The tone contrast embedded in the monosyllables evoked similar mismatch negativities (MMNs) in CI and NH children at an early stage (~200 ms). However, the amplitude of the MMN evoked by the tone contrast in the idiom context was significantly lower in CI children than in NH children. Furthermore, robust late discriminative negativity (LDN) at a late stage (~500 ms) was found only in NH children, but not in CI children. The MMN and LDN findings indicate deficits of low-level acoustic encoding in a complex context (such as an idiom) and higher-level cognitive processing in CI children, respectively. Both deficient sensory and cognitive processing may contribute to the speech perception difficulties in CI children.

Deaf Children of Hearing Parents Have Age-Level Vocabulary Growth When Exposed to American Sign Language by 6 Months of Age

OBJECTIVE

To examine whether children who are deaf or hard of hearing who have hearing parents can develop age-level vocabulary skills when they have early exposure to a sign language.

STUDY DESIGN

This cross-sectional study of vocabulary size included 78 children who are deaf or hard of hearing between 8 and 68 months of age who were learning American Sign Language (ASL) and had hearing parents. Children who were exposed to ASL before 6 months of age or between 6 and 36 months of age were compared with a reference sample of 104 deaf and hard of hearing children who have parents who are deaf and sign.

RESULTS

Deaf and hard of hearing children with hearing parents who were exposed to ASL in the first 6 months of life had age-expected receptive and expressive vocabulary growth. Children who had a short delay in ASL exposure had relatively smaller expressive but not receptive vocabulary sizes, and made rapid gains.

CONCLUSIONS

Although hearing parents generally learn ASL alongside their children who are deaf, their children can develop age-expected vocabulary skills when exposed to ASL during infancy. Children who are deaf with hearing parents can predictably and consistently develop age-level vocabularies at rates similar to native signers; early vocabulary skills are robust predictors of development across domains.