Beginning to talk like an adult: increases in speech-like utterances in young cochlear implant recipients and typically developing children

Monitoring of Communication Precursors in Extremely Low Birth Weight (ELBW) Newborns by Video Analysis Method: Preliminary Results

Background: The survival of extremely low birth weight infants (ELBW) has increased worldwide. Even in the absence of major disabilities, ELBW infants show difficulty in simple language functions. It is relevant to assess early abilities, which are the base of early linguistic skills, in order to implement customized intervention programs in ELBW infants. Aims: To evaluate communication precursors of language development in ELBW infants at 12 and 24 months of correct age (C.A). To investigate the correlation of linguistic and communicative prerequisites with mental development outcome at 24 months CA. Method: 52 ELBW neonates (mean gestational age 26.6 weeks, mean birth weight was 775 g) who were admitted to the neonatal intensive care unit of the University Hospital of Modena, were enrolled. Data were collected from archived audio-video recordings of neurodevelopmental follow-up visits. Video analysis of communicative and linguistic developmental was performed at 12 and 24 months CA. Neurodevelopmental outcome was evaluated with Mental Developmental Scales (GMDS-R). Results: The video-analysis showed that infants at 12 months CA used predominantly eye contacts and gestural turns, while vocal turns were scant. At 24 months CA, a significant change in eye contacts, vocal turns, gestural turns, and utterances (p < 0.001) occurred. The total number of utterances (p = 0.036) and eye contacts (p = 0.045) were significantly correlated to the Development Quotient (DQ) of Hearing and Language scale. Moreover, a significant correlation was found with the Personal-Social scale vocal turns (p = 0.009) and the total number of utterances (p = 0,02). Finally, the Global Quotient of the GMDS-R was related to the Vocal Turns (p = 0.034) and the total number of Utterances (p = 0.013). Conclusions: ELBW infants at 12 months CA use predominantly eye contacts and gestural turns to communicate with adults. At 24 months CA, the child’s communicative intention evolves from gestural to verbal communication. The latter is characterized by an increase in both vocal turns and the number of utterances produced during interaction. The video analysis we implement appears to be a sensitive tool for early assessment of communication and language development and to refine early intervention

Prelinguistic Vocal Development in Children With Cochlear Implants: A Systematic Review

OBJECTIVES

This systematic review is designed to (a) describe measures used to quantify vocal development in pediatric cochlear implant (CI) users, (b) synthesize the evidence on prelinguistic vocal development in young children before and after cochlear implantation, and (c) analyze the application of the current evidence for evaluating change in vocal development before and after cochlear implantation for young children. Investigations of prelinguistic vocal development after cochlear implantation are only beginning to uncover the expected course of prelinguistic vocal development in children with CIs and what factors influence that course, which varies substantially across pediatric CI users. A deeper understanding of prelinguistic vocal development will improve professionals' abilities to determine whether a child with a CI is exhibiting sufficient progress soon after implantation and to adjust intervention as needed.

DESIGN

We systematically searched PubMed, ProQuest, and CINAHL databases for primary reports of children who received a CI before 5 years 0 months of age that included at least one measure of nonword, nonvegetative vocalizations. We also completed supplementary searches.

RESULTS

Of the 1916 identified records, 59 met inclusion criteria. The included records included 1125 total participants, which came from 36 unique samples. Records included a median of 8 participants and rarely included children with disabilities other than hearing loss. Nearly all of the records met criteria for level 3 for quality of evidence on a scale of 1 (highest) to 4 (lowest). Records utilized a wide variety of vocalization measures but often incorporated features related to canonical babbling. The limited evidence from pediatric CI candidates before implantation suggests that they are likely to exhibit deficits in canonical syllables, a critical vocal development skill, and phonetic inventory size. Following cochlear implantation, multiple studies report similar patterns of growth, but faster rates producing canonical syllables in children with CIs than peers with comparable durations of robust hearing. However, caution is warranted because these demonstrated vocal development skills still occur at older chronological ages for children with CIs than chronological age peers with typical hearing.

CONCLUSIONS

Despite including a relatively large number of records, the evidence in this review regarding changes in vocal development before and after cochlear implantation in young children remains limited. A deeper understanding of when prelinguistic skills are expected to develop, factors that explain deviation from that course, and the long-term impacts of variations in vocal prelinguistic development is needed. The diverse and dynamic nature of the relatively small population of pediatric CI users as well as relatively new vocal development measures present challenges for documenting and predicting vocal development in pediatric CI users before and after cochlear implantation. Synthesizing results across multiple institutions and completing rigorous studies with theoretically motivated, falsifiable research questions will address a number of challenges for understanding prelinguistic vocal development in children with CIs and its relations with other current and future skills. Clinical implications include the need to measure prelinguistic vocalizations regularly and systematically to inform intervention planning.

The Relationship Between the Onset of Canonical Syllables and Speech Perception Skills in Children With Cochlear Implants

Purpose The study sought to determine whether the onset of canonical vocalizations in children with cochlear implants (CIs) is related to speech perception skills and spoken vocabulary size at 24 months postactivation. Method The vocal development in 13 young CI recipients (implanted by their third birthdays; mean age at activation = 20.62 months, SD = 8.92 months) was examined at every 3-month interval during the first 2 years of CI use. All children were enrolled in auditory-oral intervention programs. Families of these children used spoken English only. To determine the onset of canonical syllables, the first 50 utterances from 20-min adult-child interactions were analyzed during each session. The onset timing was determined when at least 20% of utterances included canonical syllables. As children's outcomes, we examined their Lexical Neighborhood Test scores and vocabulary size at 24 months postactivation. Results Pearson correlation analysis showed that the onset timing of canonical syllables is significantly correlated with phonemic recognition skills and spoken vocabulary size at 24 months postactivation. Regression analyses also indicated that the onset timing of canonical syllables predicted phonemic recognition skills and spoken vocabulary size at 24 months postactivation. Conclusion Monitoring vocal advancement during the earliest periods following cochlear implantation could be valuable as an early indicator of auditory-driven language development in young children with CIs. It remains to be studied which factors improve vocal development for young CI recipients.

Validation of a Parent Report Tool for Monitoring Early Vocal Stages in Infants

Purpose Tracking of infants' progression through early vocal stages supports the identification of children at risk for language delays and guides early intervention for children with disabilities. However, few clinical tools are available to support systematic assessment of infants' early vocal development. This study sought to develop and conduct a preliminary evaluation of the validity of a parent report tool designed for this purpose, the Vocal Development Landmarks Interview (VDLI). Method The participants were caregivers of 160 typically developing 6- to 21-month-old infants. Caregivers participated in the VDLI, which uses audio samples of authentic infant vocalizations to query parents regarding their children's vocal behaviors. The VDLI yields 3 subscale scores (Precanonical, Canonical, and Word) and a total score. Caregivers also completed sections of the Communication and Symbolic Behavior Scales Developmental Profile Caregiver Questionnaire that yielded a speech composite score. Results Cross-sectional analyses showed that the VDLI is sensitive to age and captures the expected developmental trajectories of vocal behaviors. A strong, positive correlation ( r = .93) was found between VDLI total scores and the Communication and Symbolic Behavior Scales Developmental Profile speech composite score, indicating concurrent validity. Subscales were found to be internally consistent. Conclusion Preliminary findings of sensitivity to age, concurrent validity, and internal consistency provide support for the eventual use of the VDLI as a clinical tool for tracking vocal and early verbal milestones. Future research will explore the level of concordance between parent report and researcher observations of child vocal behaviors. Supplemental Material https://doi.org/10.23641/asha.8330003.

Vocal Development in Infants and Toddlers With Bilateral Cochlear Implants and Infants With Normal Hearing

Purpose The purpose of this study was to investigate the time course of vocal development in infants and toddlers with bilateral cochlear implants (CIs; bilateral CI group) who are acquiring Finnish and to compare their progress to that of infants with normal hearing and typical development (TD group). Method Five thousand nine hundred sixty-four spontaneous utterances of 30 infants and toddlers (15 in both groups) were classified as either precanonical (PC) vocalizations, basic canonical syllables (BCS), or advanced forms (AF) levels. Time course of development and group differences were analyzed in a prospective longitudinal study during a time course of 1 year: before implantation and 1, 3, 6, 9, and 12 months after CI activation for the bilateral CI group and at 6, 9, and 12 months of age for the TD group. Results The least mature PC vocalizations decreased and the BCS and AF vocalizations increased for both the bilateral CI and TD groups during the follow-up period of 1 year. The bilateral CI group produced a lower percentage of PC vocalizations (effect size, η_p ² = .35) and a higher percentage of BCS (effect size, η_p ² = .16) and AF vocalizations (effect size, η_p ² = 0.24) than the TD group. Conclusions The findings of this study showed that vocal development of infants and toddlers with early-identified profound hearing loss is delayed before CI activation. Findings also showed that infants and toddlers with bilateral CIs make rapid advancements in vocal development after implantation compared to infants with typical development. However, their vocal development seems to remain delayed at least during the 1st year of bilateral CI use as compared to the well-documented milestones of infants and toddlers with typical development. Information about the vocal development time course following bilateral CI activation helps parents recognize progress in auditory-guided speech development before the emergence and the use of spoken words in communication.

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

PURPOSE

This study sought to expand understanding of the impact of cochlear implantation on grammatical acquisition by comparing young children who have vocabularies of comparable size. Two research questions were investigated: (a) Do young cochlear implant (CI) recipients have grammatical skills comparable to those of children with normal hearing (NH) matched by spoken vocabulary size? (b) Do these groups show associations between vocabulary size and grammatical measures?

METHOD

The participants included 13 CI recipients at 24 months postactivation (chronological ages = 33-60 months; M = 44.62) and 13 children with NH between 27 and 30 months old (M = 20.69). The 2 groups were matched by their vocabulary size. Four grammatical outcomes were analyzed from the MacArthur Communicative Development Inventory (Fenson, Marchman, Thal, Dale, & Reznick, 2007) and 20-min language samples: (a) grammatical complexity, (b) mean length of utterances, (c) tense marker total, and (d) productivity scores.

RESULTS

The 2 groups showed comparable grammatical skills across the 4 measures. Consistently significant associations between vocabulary size and grammatical outcomes were found in the CI group, with fewer associations in the NH group.

CONCLUSIONS

The 2 groups showed similar grammatical abilities. The young CI recipients appeared to be following a typical pattern of linguistic development.

Medical and bioethical considerations in elective cochlear implant array removal

OBJECTIVE

Cochlear explantation for purely elective (e.g. psychological and emotional) reasons is not well studied. Herein, we aim to provide data and expert commentary about elective cochlear implant (CI) removal that may help to guide clinical decision-making and formulate guidelines related to CI explantation.

DATA SOURCES

We address these objectives via three approaches: case report of a patient who desired elective CI removal; review of literature and expert discussion by surgeon, audiologist, bioethicist, CI user and member of Deaf community.

REVIEW METHODS

A systematic review using three scientific online databases was performed. Included articles addressed the benefits and/or complications of cochlear implantation in young children, CI explantation with or without revision surgery and the ethical debate between the medical and Deaf communities on cochlear implantation and explantation.

CONCLUSIONS

The medical and audiological perspectives identify a host of risks related to implant removal without reimplantation, including risk from surgery, general anaesthesia, cochlear ossification and poor audiometric outcomes. The member of the deaf community and bioethicist argue that physicians need to guide the principles of beneficence, non-maleficence and patient autonomy. Taken together, patient desires should be seen as paramount, if the patient is otherwise fit for surgery and well informed.

IMPLICATIONS FOR PRACTICE

Similar to the case of device implantation, device explantation should be a multidisciplinary and collaborative decision with the patient and the family's desires at the centre. While every case is different, we offer a CI explantation discussion to assist in clinical decision-making, patient counselling and education.

Consonant Acquisition in Young Cochlear Implant Recipients and Their Typically Developing Peers

PURPOSE

Consonant acquisition was examined in 13 young cochlear implant (CI) recipients and 11 typically developing (TD) children.

METHOD

A longitudinal research design was implemented to determine the rate and nature of consonant acquisition during the first 2 years of robust hearing experience. Twenty-minute adult-child (typically a parent) interactions were video and audio recorded at 3-month intervals following implantation until 24 months of robust hearing experience was achieved. TD children were similarly recorded between 6 and 24 months of age. Consonants that were produced twice within a 50-utterance sample were considered "established" within a child's consonant inventory.

RESULTS

Although the groups showed similar trajectories, the CI group produced larger consonant inventories than the TD group at each interval except for 21 and 24 months. A majority of children with CIs also showed more rapid acquisition of consonants and more diverse consonant inventories than TD children.

CONCLUSIONS

These results suggest that early auditory deprivation does not significantly affect consonant acquisition for most CI recipients. Tracking early consonant development appears to be a useful way to assess the effectiveness of cochlear implantation in young recipients.