Laurie S. Eisenberg

Spoken Language Development in Children Following Cochlear Implantation

CONTEXT Cochlear implantation is a surgical alternative to traditional amplification (hearing aids) that can facilitate spoken language development in young children with severe to profound sensorineural hearing loss (SNHL). OBJECTIVE To prospectively assess spoken language acquisition following cochlear implantation in young children. DESIGN, SETTING, AND PARTICIPANTS Prospective, longitudinal, and multidimensional assessment of spoken language development over a 3-year period in children who underwent cochlear implantation before 5 years of age (n = 188) from 6 US centers and hearing children of similar ages (n = 97) from 2 preschools recruited between November 2002 and December 2004. Follow-up completed between November 2005 and May 2008. MAIN OUTCOME MEASURES Performance on measures of spoken language comprehension and expression (Reynell Developmental Language Scales). RESULTS Children undergoing cochlear implantation showed greater improvement in spoken language performance (10.4; 95% confidence interval [CI], 9.6-11.2 points per year in comprehension; 8.4; 95% CI, 7.8-9.0 in expression) than would be predicted by their preimplantation baseline scores (5.4; 95% CI, 4.1-6.7, comprehension; 5.8; 95% CI, 4.6-7.0, expression), although mean scores were not restored to age-appropriate levels after 3 years. Younger age at cochlear implantation was associated with significantly steeper rate increases in comprehension (1.1; 95% CI, 0.5-1.7 points per year younger) and expression (1.0; 95% CI, 0.6-1.5 points per year younger). Similarly, each 1-year shorter history of hearing deficit was associated with steeper rate increases in comprehension (0.8; 95% CI, 0.2-1.2 points per year shorter) and expression (0.6; 95% CI, 0.2-1.0 points per year shorter). In multivariable analyses, greater residual hearing prior to cochlear implantation, higher ratings of parent-child interactions, and higher socioeconomic status were associated with greater rates of improvement in comprehension and expression. CONCLUSION The use of cochlear implants in young children was associated with better spoken language learning than would be predicted from their preimplantation scores.

Speech recognition with reduced spectral cues as a function of age

Adult listeners are able to recognize speech even under conditions of severe spectral degradation. To assess the developmental time course of this robust pattern recognition, speech recognition was measured in two groups of children (5-7 and 10-12 years of age) as a function of the degree of spectral resolution. Results were compared to recognition performance of adults listening to the same materials and conditions. The spectral detail was systematically manipulated using a noise-band vocoder in which filtered noise bands were modulated by the amplitude envelope from the same spectral bands in speech. Performance scores between adults and older children did not differ statistically, whereas scores by younger children were significantly lower; they required more spectral resolution to perform at the same level as adults and older children. Part of the deficit in younger children was due to their inability to utilize fully the sensory information, and part was due to their incomplete linguistic/cognitive development. The fact that young children cannot recognize spectrally degraded speech as well as adults suggests that a long learning period is required for robust acoustic pattern recognition. These findings have implications for the application of auditory sensory devices for young children with early-onset hearing loss.

Speech Recognition at 1-Year Follow-Up in the Childhood Development after Cochlear Implantation Study: Methods and Preliminary Findings

The Childhood Development after Cochlear Implantation (CDaCI) study is a longitudinal multicenter investigation designed to identify factors influencing spoken language in young deaf children with cochlear implants. Normal-hearing peers serve as controls. As part of a comprehensive evaluation battery, a speech recognition hierarchy was designed to assess how well these children recognize speech stimuli across developmental stages. Data were analyzed for the earliest measures in 42 pairs of children reaching 1 year of follow-up. A number of children in the cochlear implant group who met criteria for testing approached levels of performance similar to the normal-hearing controls, and some could identify sentences in competition. These results demonstrate the responsiveness of the speech recognition hierarchy in tracking emergent skills from a sample of the CDaCI cohort.

Influence Of Implantation Age On School-Age Language Performance In Pediatric Cochlear Implant Users

Abstract Objective: This study examined specific spoken language abilities of 160 children with severe-to-profound sensorineural hearing loss followed prospectively 4, 5, or 6 years after cochlear implantation. Study sample: Ninety-eight children received implants before 2.5 years, and 62 children received implants between 2.5 and 5 years of age. Design: Language was assessed using four subtests of the Comprehensive Assessment of Spoken Language (CASL). Standard scores were evaluated by contrasting age of implantation and follow-up test time. Results: Children implanted under 2.5 years of age achieved higher standard scores than children with older ages of implantation for expressive vocabulary, expressive syntax, and pragmatic judgments. However, in both groups, some children performed more than two standard deviations below the standardization group mean, while some scored at or well above the mean. Conclusions: Younger ages of implantation are associated with higher levels of performance, while later ages of implantation are associated with higher probabilities of continued language delays, particularly within subdomains of grammar and pragmatics. Longitudinal data from this cohort study demonstrate that after 6 years of implant experience, there is large variability in language outcomes associated with modifiers of rates of language learning that differ as children with implants age.

Effects of Maternal Sensitivity and Cognitive and Linguistic Stimulation on Cochlear Implant Users' Language Development over Four Years

OBJECTIVES To examine the effects of observed maternal sensitivity (MS), cognitive stimulation (CS), and linguistic stimulation on the 4-year growth of oral language in young, deaf children receiving a cochlear implant. Previous studies of cochlear implants have not considered the effects of parental behaviors on language outcomes. STUDY DESIGN In this prospective, multisite study, we evaluated parent-child interactions during structured and unstructured play tasks and their effects on oral language development in 188 deaf children receiving a cochlear implant and 97 normal-hearing children as controls. Parent-child interactions were rated on a 7-point scale using the National Institute of Child Health and Human Developments Early Childcare Study codes, which have well-established psychometric properties. Language was assessed using the MacArthur Bates Communicative Development Inventories, the Reynell Developmental Language Scales, and the Comprehensive Assessment of Spoken Language. RESULTS We used mixed longitudinal modeling to test our hypotheses. After accounting for early hearing experience and child and family demographics, MS and CS predicted significant increases in the growth of oral language. Linguistic stimulation was related to language growth only in the context of high MS. CONCLUSION The magnitude of effects of MS and CS on the growth of language was similar to that found for age at cochlear implantation, suggesting that addressing parenting behaviors is a critical target for early language learning after implantation.

Current state of knowledge: speech recognition and production in children with hearing impairment.

This review summarizes the prevalent literature covering speech recognition and production in children with mild to severe hearing impairment (HI). In general, the ability to recognize and produce speech improves as the child matures but decreases with greater severity of hearing loss. Performance scores on measures of phonetic contrast perception and word recognition are relatively high for children with mild to severe HI when compared to children with profound HI, but not as high as scores for children with normal hearing (NH). Babbling may develop at a slower rate for infants with mild to moderate HI when compared to that of infants with NH. Articulation is not severely affected by mild to severe HI and the most common errors are omissions and substitutions, particularly for fricatives and affricates. Children with mild to severe HI generally produce intelligible speech.

Electrical Stimulation of the Auditory System in Children Deafened by Meningitis

Twenty-five children deafened by meningitis were compared with 10 congenitally deaf children on cochlear implant performance. All subjects had met the audiologic criterion of profound deafness as required for implant surgery. Twenty subjects in the meningitis group had some degree of ossification at the round window, and drilling was required for electrode insertion into the scala tympani. In six of these subjects, bone completely filled the scala. There was a significant relationship between extensive ossification and the etiologic pathogen Diplococcus pneumoniae, as determined by radiologic and surgical reports. Postoperative results revealed that all subjects could be electrically stimulated, except for one with extensive bone formation. On implant performance, the meningitis group demonstrated sound-field thresholds comparable to those of the group with congenital deafness but required significantly higher voltage settings. These findings suggest that even with extensive labyrinthine ossification caused by meningitic deafness, neural elements are present and can be stimulated if enough power can be safely provided.

Spoken word recognition development in children with residual hearing using cochlear implants and hearing AIDS in opposite ears.

Objective: With broadening candidacy criteria for cochlear implantation, a greater number of pediatric candidates have usable residual hearing in their nonimplanted ears. This population potentially stands to benefit from continued use of conventional amplification in their nonimplanted ears. The purposes of this investigation were to evaluate whether children with residual hearing in their nonimplanted ears benefit from bilateral use of cochlear implants and hearing aids and to investigate the time course of adaptation to combined use of the devices together. Design: Pediatric cochlear implant recipients with severe sensorineural hearing loss in their nonimplanted ears served as participants. Ten children continued to use hearing aids in their nonimplanted ears after cochlear implantation; 12 children used their cochlear implants exclusively. Participants were tested longitudinally on spoken word recognition measures at 6-month intervals. The children who continued wearing hearing aids were tested in three sensory aid conditions: cochlear implants alone, hearing aids alone, and cochlear implants in conjunction with hearing aids. The children who did not continue hearing aid use were tested after surgery in their only aided condition, cochlear implant alone. Results: The results suggest that children with severe hearing loss who continued using hearing aids in their nonimplanted ears benefited from combining the acoustic input received from a hearing aid with the input received from a cochlear implant, particularly in background noise. However, this benefit emerged with experience. Conclusions: Our findings suggest that it is appropriate to encourage pediatric cochlear implant recipients with severe hearing loss to continue wearing an appropriately fitted hearing aid in the nonimplanted ear to maximally benefit from bilateral stimulation.

Assessing the Use of Speech and Language Measures in Relation to Parental Perceptions of Development After Early Cochlear Implantation

Objective: Clinicians and investigators use multiple outcome measures after early cochlear implantation (CI) to assess auditory skills, speech, and language effects. Are certain outcome measures better associated with optimal childhood development from the perspective of parents? We studied the association between several commonly used outcome instruments and a measure of parental perceptions of development to gain insight into how our clinical tests reflect parental perceptions of a childs developmental status. Study Design: Cross-sectional analysis. Setting: Six academic centers. Patients: One hundred eighty-eight deaf children (<6 yr) 1 year after CI activation enrolled in the longitudinal Childhood Development after CI study. Main Outcome Measures: Measures of auditory skills, speech, and language. Parental perceptions of development quantified with a visual analogue scale (visual analogue scale-development). Methods: Nonparametric and parametric regression methods were used to model the relationship between outcome measures and visual analogue scale-development scores. Results: All outcome measures were positively associated with parental perceptions of development, but more robust associations were observed with language measures and a parent-report scale of auditory skills than with a selected measure of closed-set speech. For speech and language data, differences were observed in the trajectories of associations among younger (2-3 yr) versus older (4-5 yr) children. Conclusion: Our results demonstrate the importance of measuring multiple outcome measures after early pediatric CI. The degree to which an outcome measure reflects childhood development as perceived by parents may be affected by the childs age. Measures that are based on parental report and broader outcome measures focused on verbal language offer the potential for a fuller understanding of the true effectiveness of early implantation.

Comprehensive Evaluation of a Child With an Auditory Brainstem Implant

Objective: We had an opportunity to evaluate an American child whose family traveled to Italy to receive an auditory brainstem implant (ABI). The goal of this evaluation was to obtain insight into possible benefits derived from the ABI and to begin developing assessment protocols for pediatric clinical trials. Study Design: Case study. Setting: Tertiary referral center. Patient: Pediatric ABI Patient 1 was born with auditory nerve agenesis. Auditory brainstem implant surgery was performed in December, 2005, in Verona, Italy. The child was assessed at the House Ear Institute, Los Angeles, in July 2006 at the age of 3 years 11 months. Follow-up assessment has continued at the HEAR Center in Birmingham, Alabama. Intervention: Auditory brainstem implant. Main Outcome Measures: Performance was assessed for the domains of audition, speech and language, intelligence and behavior, quality of life, and parental factors. Results: Patient 1 demonstrated detection of sound, speech pattern perception with visual cues, and inconsistent auditory-only vowel discrimination. Language age with signs was approximately 2 years, and vocalizations were increasing. Of normal intelligence, he exhibited attention deficits with difficulty completing structured tasks. Twelve months later, this child was able to identify speech patterns consistently; closed-set word identification was emerging. These results were within the range of performance for a small sample of similarly aged pediatric cochlear implant users. Conclusion: Pediatric ABI assessment with a group of well-selected children is needed to examine risk versus benefit in this population and to analyze whether open-set speech recognition is achievable.