Normal Hearing Child Research Articles

How Vocal Emotions Produced by Children With Cochlear Implants Are Perceived by Their Hearing Peers.

Purpose Cochlear implants (CIs) transmit a degraded version of the acoustic input to the listener. This impacts the perception of harmonic pitch, resulting in deficits in the perception of voice features critical to speech prosody. Such deficits may relate to changes in how children with CIs (CCIs) learn to produce vocal emotions. The purpose of this study was to investigate happy and sad emotional speech productions by school-age CCIs, compared to productions by children with normal hearing (NH), postlingually deaf adults with CIs, and adults with NH. Method All individuals recorded the same emotion-neutral sentences in a happy manner and a sad manner. These recordings were then used as stimuli in an emotion recognition task performed by child and adult listeners with NH. Their performance was taken as a measure of how well the 4 groups of talkers communicated the 2 emotions. Results Results showed high variability in the identifiability of emotions produced by CCIs, relative to other groups. Some CCIs produced highly identifiable emotions, while others showed deficits. The postlingually deaf adults with CIs produced highly identifiable emotions and relatively small intersubject variability. Age at implantation was found to be a significant predictor of performance by CCIs. In addition, the NH listeners' age predicted how well they could identify the emotions produced by CCIs. Thus, older NH child listeners were better able to identify the CCIs' intended emotions than younger NH child listeners. In contrast to the deficits in their emotion productions, CCIs produced highly intelligible words in the sentences carrying the emotions. Conclusions These results confirm previous findings showing deficits in CCIs' productions of prosodic cues and indicate that early auditory experience plays an important role in vocal emotion productions by individuals with CIs.

Infant-directed speech register in children with and without hearing loss

Do children with hearing loss use infant-directed speech? The study examined speech characteristics of a 6-year-old child with bilateral cochlear implants and an age-matched child with normal-hearing while interacting with their infant siblings (age 29 and 20 months) and with their mothers. Child-sibling and child-mother interactions were recorded in two conditions. In the “toy” condition, the children explained to their siblings and their mothers how to assemble a toy. In the “book” condition, the children narrated a story using a picture book. Sixty-five vocalizations from each child’s speech sample were extracted in each condition. Mean fundamental frequency, fundamental frequency range, utterance duration, number of syllables per utterance, and speech rate were measured. Both children produced higher fundamental frequency, expanded fundamental frequency range, shorter utterance duration, and slower speech rate in the sibling- compared to mother-directed speech in both the “book” and “toy” conditions. For the mother-directed speech only, the children produced lower fundamental frequency, longer utterance duration and more syllables per utterance in the “book” than the “toy” condition. The results suggest that children with and without hearing loss modify prosodic characteristics of their speech when interacting with a younger sibling but the strength of the modification may be task-dependent.

Naturalistic coding for prelinguistic speech at 9 and 12 months of age from two Mandarin-learning children differing in auditory function

This study investigated the feasibility of Fagan’s (2005) naturalistic coding system for prelinguistic speech of Mandarin-learning children. This system includes 10 categories: single vowel, single consonant, consonant combination, vowel combination, syllable containing glottal sound and vowel, syllable containing supra-glottal consonant and vowel (SGCV), reduplicated vowel, reduplicated consonant, reduplicated CV, and reduplicated “SGCV" (RSGCV). The first 50 clear utterances produced by one normal-hearing (NH) child and one hearing-impaired (HI) child in the audio recordings at 9 and 12 months old were transcribed into 10 categories for comparison. Major findings are (1) compared with NH child, HI child demonstrated no obvious changes in vocalization from 9 to 12 months old; (2) at 12 months old, canonical babbling ratio of HI child was 0, while those of NH child were 0.84 (utterance as unit) and 0.48 (syllable as unit); (3) compared with NH child, HI child did not manipulate supra-glottal sounds and had limited consonant inventory; (4) HI child produced no RSGCV (e.g., /baba/) while NH child was at reduplicated babbling stage at 12 months old. Naturalistic coding system revealed difference in prelinguistic speech between a NH child and a HI child. More participants should be included to verify the findings.

Identification of a novel homozygous mutation in transmembrane channel like 1 (TMC1) gene, one of the second-tier hearing loss genes after GJB2 in India.

Background & objectives:Hearing impairment is a common and heterogeneous sensory disorder in humans. Among about 90 genes, which are known to be associated with hearing impairment, mutations in the GJB2 (gap junction protein beta 2) gene are the most prevalent in individuals with hereditary hearing loss. Contribution of the other deafness-causing genes is relatively poorly understood. Here, we present our findings on two families with transmembrane channel like 1 (TMC1) gene variants of the 47 families with nonsyndromic hearing loss (NSHL) studied.Methods:Forty seven families including 26 consanguineous families with at least two hearing impaired children and one normal hearing child and 21 non-consanguineous families having at least three hearing impaired children and one normal hearing child were enrolled for this study. Genetic linkage studies were carried out in 41 families that were GJB2 (Connexin 26) negative. Seven polymorphic short tandem repeat markers at the DFNB7/11 locus were studied employing fluorescently labelled markers.Results:A novel homozygous missense mutation c.1283C>A (p.Ala428Asp) was identified co-segregating with hearing loss. This change results in substitution of a highly conserved polar alanine to a charged aspartic acid and is predicted to be deleterious. In addition, a previously reported nonsense mutation, p.R34X in TMC1, was found.Interpretation & conclusions:While mutations in TMC1 are not as common a cause of NSHL as those in GJB2, TMC1 should be considered for diagnostic investigations in cases of NSHL in GJB2-negative families.

Parental comparison of the prosodic and paralinguistic ability of children with cochlear implants and their normal hearing siblings

The everyday communication of children is commonly observed by their parents. This paper examines the responses of parents (n = 18) who had both a Cochlear Implant (CI) and a Normal Hearing (NH) child. Through an online questionnaire, parents rated the ability of their children on a gamut of speech communication competencies encountered in everyday settings. Comparative parental ratings of the CI children were significantly poorer than those of their NH siblings in speaker recognition, happy and sad emotion, and question versus statement identification. Parents also reported that they changed the vocal effort and the enunciation of their speech when they addressed their CI child and that their CI child consistently responded when their name was called in normal, but not in noisy backgrounds. Demographic factors were not found to be linked to the parental impressions.

Hearing loss associated with an unusual mutation combination in the gap junction beta 2 (GJB2) gene in a Chinese family

ObjectiveTo assess the molecular etiology of nonsyndromic sensorineural hearing loss (NSHL) in members of an affected Chinese family. MethodsCommon hearing-related genes including gap junction beta 2 (GJB2), SLC26A4, mitochondrial DNA 12S rRNA, GJB3 and GJB6 were examined in a family consisting of a normal hearing father, an NSHL-affected mother, one normal-hearing child and three NSHL-affected children. Specific primers were used in polymerase chain reactions to amplify the coding regions of the above genes from the peripheral blood DNA from each family member, and the genes were analyzed by direct sequencing. The subjects were evaluated for phenotypic characterization using audiometric testing and radiological examination of the inner ear. ResultsPathogenic mutations in the GJB2 gene were identified. The affected mother showed a heterozygous G→A transition at nucleotide 232, resulting in an alanine to threonine substitution at codon 78 (p.A78T), and the normal hearing father had a c.35insG insertion mutation. The three affected children displayed heterozygosity for the GJB2 mutations, showing a previously unreported combination of c.35insG and c.232G>A. ConclusionsThe GJB2 mutations account for a significant proportion of NSHL in affected individuals worldwide. Genetic and audiological data analysis of a Chinese family with NSHL revealed a novel c.35insG/c.232G>A compound heterozygous state. Our results highlight the complexity of the GJB2 genotypes and phenotypes.

Tone duration and tonal slope of a cochlear implant child in comparison with a normal hearing child: A longitudinal study of a pair of twins

The aim of this study is to observe the tonal acquisition in a pair of fraternal twins from 1 to 3 years old, making a comparison between a child with cochlear implant (Child A) and a child with normal hearing (Child B). Spontaneous data were transcribed and later tone duration and tonal slope were measured by Praat. Four main tones in Mandarin were analyzed: high-level, high-rising, high-falling, and low-falling tones. Major findings are: 1) Tone duration of Child B is longer than that of Child A by 1.2-1.7 times. The average of tone duration in Child A is 250ms-260ms; 2) In Child A, high-level tones show the shortest duration among the four main tones, and high-rising tones are the longest; 3)Tonal slope of Child A is flatter than in Child B. The absolute value of tonal slope is higher in Child B; 4) Children control high-level tone the best, followed by high-rising, then high-falling, and low-falling the last.

C042 Auditory brainstem implantation outcomes: Longitudinal study results

To assess the molecular etiology of nonsyndromic sensorineural hearing loss (NSHL) in members of an affected Chinese family.Common hearing-related genes including gap junction beta 2 (GJB2), SLC26A4, mitochondrial DNA 12S rRNA, GJB3 and GJB6 were examined in a family consisting of a normal hearing father, an NSHL-affected mother, one normal-hearing child and three NSHL-affected children. Specific primers were used in polymerase chain reactions to amplify the coding regions of the above genes from the peripheral blood DNA from each family member, and the genes were analyzed by direct sequencing. The subjects were evaluated for phenotypic characterization using audiometric testing and radiological examination of the inner ear.Pathogenic mutations in the GJB2 gene were identified. The affected mother showed a heterozygous G → A transition at nucleotide 232, resulting in an alanine to threonine substitution at codon 78 (p.A78T), and the normal hearing father had a c.35insG insertion mutation. The three affected children displayed heterozygosity for the GJB2 mutations, showing a previously unreported combination of c.35insG and c.232G>A.The GJB2 mutations account for a significant proportion of NSHL in affected individuals worldwide. Genetic and audiological data analysis of a Chinese family with NSHL revealed a novel c.35insG/c.232G>A compound heterozygous state. Our results highlight the complexity of the GJB2 genotypes and phenotypes.

Auditory, speech and language development in young children with cochlear implants compared with children with normal hearing

Objective This study had two aims: (1) to document the auditory and lexical development of children who are deaf and received the first cochlear implant (CI) by the age of 16 months and the second CI by the age of 31 months and (2) to compare these children's results with those of children with normal hearing (NH). Methods This longitudinal study included five children with NH and five with sensorineural deafness. All children of the second group were observed for 36 months after the first fitting of the device (cochlear implant). The auditory development of the CI group was documented every 3 months up to the age of two years in hearing age and chronological age and for the NH group in chronological age. The language development of each NH child was assessed at 12, 18, 24 and 36 months of chronological age. Children with CIs were examined at the same age intervals at chronological and hearing age. Results In both groups, children showed individual patterns of auditory and language development. The children with CIs developed differently in the amount of receptive and expressive vocabulary compared with the NH control group. Three children in the CI group needed almost 6 months to make gains in speech development that were consistent with what would be expected for their chronological age. Overall, the receptive and expressive development in all children of the implanted group increased with their hearing age. Conclusion These results indicate that early identification and early implantation is advisable to give children with sensorineural hearing loss a realistic chance to develop satisfactory expressive and receptive vocabulary and also to develop stable phonological, morphological and syntactical skills for school life. On the basis of these longitudinal data, we will be able to develop new diagnostic tools that enable clinicians to assess child's progress in hearing and speech development.

Receptive (aural) vocabulary development in children with permanent bilateral sensorineural hearing impairment

The receptive (aural) vocabulary development of children with binaural-aided residual hearing was investigated in a prospective longitudinal analysis (repeated measures). Thirty-three children with sensorineural hearing loss, without major co-morbidities (mean age at the first testing point, 56.2 months, standard deviation 19.0 months) were recruited from the 1994 German Goettinger Hearing Language Register. Their receptive vocabulary was measured using standardised tests (with reference to normal hearing child performance) on three separate test points (mean follow up, 18.7 months, standard deviation 5.0 months). On average, the study group scored below the normal range at the first and second tests and made a significant improvement at the last test. The degree of hearing loss was found to be significantly correlated to vocabulary performance at all time points, with increasing correlation coefficients. At the third test, significant predictive variables for successful receptive vocabulary outcome were found to be: degree of hearing loss (t = 5.43; p < 0.0001); age at diagnosis (t = 2.29; p = 0.03); and nonverbal intelligence (t = 2.82; p = 0.009). If permanent childhood hearing impairment is mild and/or is detected early, and if the child grows up in a monolingual environment, the development of receptive vocabulary within the normal range is possible.

注意欠陥多動性障害を合併した人工内耳装用聾児と健聴児の双生児での母子関係の検討

注意欠陥多動性障害を合併した人工内耳装用聾児と健聴児の双生児での母子関係の検討

The Rationale for Early Identification and Intervention

The normal hearing child utilizes auditory data to trigger his innate propensity for language learning and begins to use these stored auditory images long before he says his first word. The auditory modality appears to provide the input from which he abstracts and regularizes the rule of grammar both from outside sources and in an auditory feedback arrangement from his own utterances. The development of expressive language appears to occur rapidly once the first word is said, and by age three he appears to be using all the basic structures of speech. The child with severe hearing impairment, on the other hand, deprived of auditory input, either does not develop speech or may with some training develop very limited speech. Since most hearing impaired children can benefit from amplification, hearing aids can provide a means to maximize the auditory channel. Many such children, however, do not receive hearing aids until three to four years of age, and so have already been deprived of these key years in language development. They have already missed the critical periods in language learning and thus are apt to remain severely depressed in language skills at best. The results of one study reported in this discussion appear to substantiate the observation that a good program of early intervention, including effective parent training and early use of hearing aids to exploit auditory potential, can help hearing impaired children to generate spontaneous spoken language more comparable to that used by their normal hearing peers in both type and level of utterance. Although this language may be more immature or less syntactically and morphologically correct than that of their normal hearing peers, it compares in syntactical structure much more favorably than does the language of hearing impaired children who have not received such special help until about two years later. The study further demonstrates the importance of early intervention and illustrates the positive effects of a good early management program on the language and resulting educational achievement of hearing impaired children.