Improvements in speech perception by children with profound prelingual hearing loss: effects of device, communication mode, and chronological age

The present investigation expanded on an earlier study by Miyamoto, Osberger, Todd, Robbins, Karasek, et al. (1994) who compared the speech perception skills of two groups of children with profound prelingual hearing loss. The first group had received the Nucleus multichannel cochlear implant and was tested longitudinally. The second group, who were not implanted and used conventional hearing aids, was tested at a single point in time. In the present study, speech perception scores were examined over time for both groups of children as a function of communication mode of the child. Separate linear regressions of speech perception scores as a function of age were computed to estimate the rate of improvement in speech perception abilities that might be expected due to maturation for the hearing aid users (n=58) within each communication mode. The resulting regression lines were used to compare the estimated rate of speech perception growth for each hearing aid group to the observed gains in speech perception made by the children with multichannel cochlear implants. A large number of children using cochlear implants (n=74) were tested over a long period of implant use (m=3.5 years) that ranged from zero to 8.5 years. In general, speech perception scores for the children using cochlear implants were higher than those predicted for a group of children with 101-110 dB HL of hearing loss using hearing aids, and they approached the scores predicted for a group of children with 90-100 dB HL of hearing loss using hearing aids.     

A modification of play audiometry to assess speech discrimination ability in severe-profoundly deaf 2- to 4-year-old children

OBJECTIVE: The aim was to develop an assessment procedure that was independent of language and speech production ability, to test speech feature discrimination in severe-profoundly deaf children 2 to 4 yr of age. DESIGN: The procedure being trialed was adapted from existing procedures. The child was required to respond with a game-like motor response to a "change" in a speech stimulus that was being presented repeatedly through a speaker. The change occurred at randomly determined times, and false alarm responses were measured during the waiting periods (while the child waited for the change). Two- to four-yr-old normally hearing children and hearing-impaired children using hearing aids and a group of 4-yr-old hearing-impaired children using cochlear implants were assessed on the task. RESULTS: More than 82% of the 3- and 4-yr-old normally hearing and hearing-impaired children were able to complete the testing for the eight speech sound contrasts within three 20 minute sessions. Fifty percent of the 2-yr-old normally hearing and hearing-impaired children were able to condition and complete the task. All of the normally hearing children who completed the task successfully discriminated all speech sound contrasts. The performance of the hearing-impaired children using hearing aids was influenced by the degree of hearing loss and the type of speech contrast being tested. Similarly, the average performance of the children using cochlear implants was better for easier contrasts such as /ba/bi/ with contrasting vowel formant cues. CONCLUSIONS: This procedure has potential for use as a reliable clinical and research tool for assessing the development of auditory discrimination ability in 2- to 4-yr-old severe-profoundly deaf children.     

Speech perception test in Italian language for profoundly deaf children

Speech perception tests are an important part of procedures for diagnosing pre-verbal hearing loss. Merely establishing a child's hearing threshold with and without a hearing aid is not sufficient to ensure an adequate evaluation with a view to selecting cases suitable for cochlear implants because it fails to indicate the real benefit obtained from using a conventional hearing aid reliably. Speech perception tests have proved useful not only for patient selection, but also for subsequent evaluation of the efficacy of new hearing aids, such as tactile devices and cochlear implants. In clinical practice, the tests most commonly adopted with small children are: The Auditory Comprehension Test (ACT), Discrimination after Training (DAT), Monosyllable, Trochee, Spondee tests (MTS), Glendonald Auditory Screening Priocedure (GASP), Early Speech Perception Test (ESP), Rather than considering specific results achieved in individual cases, reference is generally made to the four speech perception classes proposed by Moog and Geers of the CID of St. Louis. The purpose of this classification, made on the results obtained with suitably differentiated tests according to the child's age and language ability, is to detect differences in perception of a spoken message in ideal listening conditions. To date, no italian language speech perception test has been designed to establish the assessment of speech perception level in children with profound hearing impairment. We attempted, therefore, to adapt the existing English tests to the Italian language taking into consideration the differences between the two languages. Our attention focused on the ESP test since it can be applied to even very small children (2 years old). The ESP is proposed in a standard version for hearing-impaired children over the age of 6 years and in a simplified version for younger children. The rationale we used for selecting Italian words reflect the rationale established for the original version, but the choice of single words follows different criteria from the original version. In fact, the two languages differ in important linguistic features so that the test can not be not adapted to the Italian language by simply translating the words involved. As currently there is no children's language dictionary in Italian arranged according to age bracket, we chose words used in children and in pre-school reading material.     

Implant cochléaire et développement des échanges conversationnels.

Most researches conducted in the field of postimplant assessment have focused on the restoration of perceptual capabilities and the development of verbal language. In contrast, only very few studies have examined the impact of a cochlear implantation on children's overall development and, in particular, on their conversational language abilities. However, some previous works on the preverbal development revealed the recurrent difficulties experienced by deaf children in acquiring knowledge of social rules and social skills relative to speech activities. In children with profound bilateral deafness, a conventional hearing aid is not enough to provide sufficiently relevant information for a satisfactory development of oral communication. In such situations, the most suitable way of improving hearing is the use of a cochlear implant. The authors therefore hypothesized that access to oral perception will not only improve implanted children's social skills, but will also increase their rate of participation and the use of verbal language in their interaction with a familiar adult (mother or father). Their communication skills profile would resemble that of younger normal hearing children. Using conversational samples from a video-filming protocol at specific intervals, the authors monitored the development of communication skills in a group of 20 prelingually, profoundly deaf children (mean age: 3.7 years). Results corroborated our hypothesis. They indicated that children using cochlear implants increased their overall performance in communication skills, quantitatively and qualitatively speaking, even at the first year postimplantation stage. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hearing, speech, language, and vestibular disorders in the fetal alcohol syndrome: a literature review

Fetal alcohol syndrome (FAS) is characterized in part by mental impairment, as well as craniofacial and ocular anomalies. These conditions are traditionally associated with childhood hearing disorders, because they all have a common embryonic origin in malformations of the first and second branchial arches, and have similar critical periods of vulnerability to toxic insult. A review of human and animal research indicates that there are four types of hearing disorders associated with FAS. These are: (1) a developmental delay in auditory maturation, (2) sensorineural hearing loss, (3) intermittent conductive hearing loss due to recurrent serous otitis media, and (4) central hearing loss. The auditory and vestibular systems share the same peripheral apparatuses (the inner ear and eighth cranial nerve) and are embryologically and structurally similar. Consequently, vestibular disorders in FAS children might be expected. The evidence for vestibular dysfunction in FAS is ambiguous, however. Like other syndromes associated with craniofacial anomalies, hearing disorders, and mental impairment, FAS is also characterized by a high prevalence of speech and language pathology. Hearing disorders are a form of sensory deprivation. If present during early childhood, they can result in permanent hearing, language, and mental impairment. Early identification and intervention to treat hearing, language, and speech disorders could therefore result in improved outcome for the FAS child. Specific recommendations are made for intervention and future research.     

Hearing capacity and speech production in 417 children with facial cleft abnormalities

Children with cleft palates often suffer from chronic conductive hearing losses, delayed language acquisition and speech disorders. This study presents results of speech and language outcomes in relation to hearing function and types of palatal malformations found. 417 children with cleft palates were examined during followup evaluations that extended over several years. Disorders were studied as they affected the ears, nose and throat, audiometry and speech and language pathology. Children with isolated cleft lips were excluded. Among the total group, 8% had normal speech and language development while 92% had speech or language disorders. 80% of these latter children had hearing problems that predominantly consisted of fluctuating conductive hearing losses caused by otitis media with effusion. 5% had sensorineural hearing losses. Fifty-eight children (14%) with rhinolalia aperta were not improved by speech therapy and required velopharyngoplasties, using a cranial-based pharyngeal flap. Language skills did not depend on the type of cleft palate presents but on the frequency and amount of hearing loss found. Otomicroscopy and audiometric follow-ups with insertions of ventilation tubes were considered to be most important for language development in those children with repeated middle ear infections. Speech or language therapy was necessary in 49% of the children.     

Effectiveness of child-health screening

Screening for sensory problems in pre-school children often fails to detect a significant number of hearing problems sufficiently early. Evidence suggests neonatal screening is more effective and cost-effective than the infant distraction test at detecting congenital hearing loss. It is not yet clear how best to identify children with speech and language delay who will fail to progress without treatment.     

The assembly of Ni2+-actin: some peculiarities

Cochlear implants have been very successful in restoring partial hearing to profoundly deaf people. Many individuals with implants are now able to communicate and understand speech without lip-reading, and some are able to talk over the phone. Children with implants can develop spoken-language skills and attend normal schools (i.e., schools with normal-hearing children). The greatest benefits with cochlear implantation have occurred in patients who (1) acquired speech and language before their hearing loss, and (2) have shorter duration of deafness. Gradual, but steady, improvements in speech production and speech perception have also occurred in prelingually deafened adults or children.     

Communication of oral deaf and normally hearing children at 36 months of age

Eighteen orally educated deaf and 18 normally hearing 36-month-old children were observed in a play session with their mother. Communicative behavior of the child was coded for modality and communicative function. Although the oral deaf children used a normal range of functions, both the quantity and proportions differed from normally hearing children. Whereas the normally hearing 3-year-olds used speech almost exclusively, the deaf children exhibited about equal use of speech, vocalizations, and gestures. Spoken language scores of the deaf children at 5 years of age were best predicted by (a) more frequent use of speech at age 36 months, (b) more frequent use of the Statement function, and (c) relatively infrequent use of the Directive function. It is suggested that some communicative functions are more informative or heuristic than others, and that the early use of these functions is most likely to predict later language competence.     

Communication between deaf children and their hearing mothers: the role of language, gesture, and vocalizations

In the present longitudinal study, 20 deaf and 20 hearing children were observed during free play with their hearing mothers when the children were 22 months and 3 years of age. Compared to hearing children, deaf children were severely language delayed, with deaf 3-year-olds using less language (speech or sign) than hearing 22-month-olds. Deaf children communicated primarily through nonlinguistic vocalizations, with increasing use of gesture from 22 months to 3 years of age. Although mothers of deaf children used more visual communication than mothers of hearing children, they still primarily communicated through speech. In addition, deaf children did not visually attend to much of their mothers' communication. Therefore, deaf children received much less communication than hearing children. These results suggest that intervention efforts should be focused on increasing the quantity of perceived linguistic input by the child.     

Presbyacusis, hearing aids and aging

This paper considers the factors of presbyacusis and age-related psychological changes in older adults in terms of their effects on the use or potential use of hearing aids as a means of improving aural communication. Data are presented on the prevalence of hearing impairment and the extent of hearing aid use in aging listeners. Four major classes of presbyacusis are described (sensory, neural, metabolic, and cochlear conduvtive) and a hearing aid prognosis is made for each type of disorder. It is shown that aging produces deficits in pure-tone thresholds, the speech reception threshold, and speech discrimination, but not all losses can be 'corrected' with a hearing aid. Binaural (stereophonic) devices are psychoacoustically superior to monaural devices; however, behavioral and personality changes in older patients often create problems of adaptation to the binaural aid. These changes may also affect the fitting of an aid and the patient's ability to learn to use it. Some practical suggestions are offered on the evaluation of hearing aids and it is emphasized that adequate orientation and counseling are typically required if hearing aid treatment is to be successful in presbyacusis.     

Physical diagnostic procedures: whispered speech and tuning fork test]

Hearing impairment occurs in 10% of the Dutch population and may lead to major communication problems and even social isolation. A good method to detect hearing loss in a general practice is the screening audiometer. The treating physician may further use the whispered speech test and tuning fork tests which together give a good impression of the severity and the nature of the hearing loss if any. The whispered speech test is best performed in the standardized form according to the guideline 'Slechthorendheid' [hardness of hearing] of the Dutch College of General Practitioners (NHG), in which certain combinations of letters are recommended. The tuning fork tests according to Rinne and Weber indicate a difference in perception and conduction deafness, and are decisive for any hearing asymmetry. Use of the whispered speech test and of the tuning fork tests is recommended for adults and children from the age of 7.     

The effectiveness of voice therapy for patients with non-organic dysphonia

OBJECTIVE: To compare how children who use either cochlear implants (CIs) or hearing aids (HAs) express English inflectional morphemes during conversation, i.e., with voice, with sign, or with both. A secondary objective was to investigate the relationship between morpheme use in pediatric CI users and their speech perception skills, length of experience with the device, and accuracy of phoneme production. DESIGN: Group 1 consisted of 25 children who used CIs, and Group 2 consisted of 13 children who used HAs. All children were prelingually deafened and all used simultaneous communication. A 12 minute spontaneous conversation was elicited, transcribed and coded. Between group comparisons were performed to evaluate differences in modality and number of morphemes used. Additionally, use of morpheme endings was related to length of CI experience, accuracy of phoneme production, and closed-set speech recognition performance. RESULTS: Children who had CI experience produced significantly more English inflected morphemes than children in the HA group. CI participants also expressed the inflected endings by using voice-only mode 91% of the time, whereas HA participants used voice-only mode 1% of the time. In the CI group, a strong relationship was found between number of morpheme endings used and speech recognition scores, length of CI experience and accuracy of phoneme production. The results of this study indicate that input from the CI facilitates children's ability to perceive and comprehend bound morphemes.     

Variability in deaf children's spelling: The effect of language experience.

French-speaking hearing and deaf children, ranging in age from 6 years 10 months to 14 years 7 months were required to spell words including phoneme-to-grapheme correspondences that were either statistically dominant or nondominant. Of interest was whether the nature of linguistic experience (cued speech vs. sign language) and the precocity of such experience (early vs. late exposure) determines accuracy in the use of phoneme-to-grapheme knowledge. Cued speech is a system delivering phonemically augmented speechreading through the visual modality. Hearing and deaf children exposed to cued speech early at home relied on accurate phoneme-to-grapheme correspondences, whereas children exposed to cued speech later and at school only, and children exposed to sign language, did not. A critical factor in the development of the phonological route for spelling seems to be early and intensive exposure to a system making all phonological distinctions easily perceivable. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cochlear implants: selection criteria and shifting borders

Cochlear implants have proven to be effective and reliable in postlingually deaf adults. This is also true for congenitally deaf and perilingually deaf children up to the age of six years. Due to the increasing experience, the improvement of implant technology and the proven reliability the selection criteria are broadened with shifting borders. The main extensions are related to age, additional handicaps, residual hearing and special etiologies of deafness. Increasing evidence shows that very early implantation results in better performance and better hearing and speech development. Near-normal language acquisition can be achieved in children implanted under the age of four. Additional handicaps do not automatically exclude a candidate from cochlear implantation. A case-to-case decision has to be made based on additional diagnostics and the experience of the implant centre. A list of suitable handicaps is provided. Severely hearing impaired patients may also be considered for cochlear implantation if their residual hearing provides no benefit for speech discrimination. The same holds true for children. Cochlear implantation in obliterated cochleae and inner ear malformation requires a special surgical technique and special electrode arrays. In this way even difficult cases can be managed with remarkable outcome. Over all, the selection criteria have been broadened with increasing experience and technological improvement. This development may continue and the borderline between hearing aids and cochlear implants will shift further towards severe hearing loss. However, the basis for success still remains good rehabilitation, a team approach and the willingness of the patient to undergo the whole process of cochlear implantation.     

Response latencies in auditory sentence comprehension: Effects of linguistic versus perceptual challenge.

Older adults with good hearing and with mild-to-moderate hearing loss were tested for comprehension of spoken sentences that required perceptual effort (hearing speech at lower sound levels), and two degrees of cognitive load (sentences with simpler or more complex syntax). Although comprehension accuracy was equivalent for both participant groups and for young adults with good hearing, hearing loss was associated with longer response latencies to the correct comprehension judgments, especially for complex sentences heard at relatively low amplitudes. These findings demonstrate the need to take into account both sensory and cognitive demands of speech materials in older adults' language comprehension. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Language learning impairments: integrating basic science, technology, and remediation

One of the fundamental goals of the modern field of neuroscience is to understand how neuronal activity gives rise to higher cortical function. However, to bridge the gap between neurobiology and behavior, we must understand higher cortical functions at the behavioral level at least as well as we have come to understand neurobiological processes at the cellular and molecular levels. This is certainly the case in the study of speech processing, where critical studies of behavioral dysfunction have provided key insights into the basic neurobiological mechanisms relevant to speech perception and production. Much of this progress derives from a detailed analysis of the sensory, perceptual, cognitive, and motor abilities of children who fail to acquire speech, language, and reading skills normally within the context of otherwise normal development. Current research now shows that a dysfunction in normal phonological processing, which is critical to the development of oral and written language, may derive, at least in part, from difficulties in perceiving and producing basic sensory-motor information in rapid succession--within tens of ms (see Tallal et al. 1993a for a review). There is now substantial evidence supporting the hypothesis that basic temporal integration processes play a fundamental role in establishing neural representations for the units of speech (phonemes), which must be segmented from the (continuous) speech stream and combined to form words, in order for the normal development of oral and written language to proceed. Results from magnetic resonance imaging (MRI) and positron emission tomography (PET) studies, as well as studies of behavioral performance in normal and language impaired children and adults, will be reviewed to support the view that the integration of rapidly changing successive acoustic events plays a primary role in phonological development and disorders. Finally, remediation studies based on this research, coupled with neuroplasticity research, will be presented.     

Hematopoietic growth factors and transfusion medicine

Some children with severe motor disorders have unintelligible speech, and may be recommended augmentative communication systems, such as a symbol chart or a voice output aid. The paper reports the outcome after 15-18 months for 35 children of recommendations for augmentative communication. Using structured questionnaires, parents were asked whether equipment was provided as recommended. Their perception of success in children's use of augmentative aids was recorded and related to potentially influential factors. Twenty-five symbol systems, 10 speech output devices and 11 switches were received; 18 symbol systems were used for communication and 10 were used frequently. Seven speech output devices were used for communication but only two were reported to be used frequently. Factors leading to more successful outcomes include early receipt of the aid, perceived adequate local training in the use of the aid, and children aged 6 years or more at initial assessment. The findings also suggest that referring professionals will need to be better informed about the nature and limitations of augmentative communication aids, and that improved local professional input and careful interagency planning and co-ordination are required to achieve optimal outcome.     

Hearing research career development for deaf students

One goal of the Americans with Disabilities Act is to enhance access to career opportunities for individuals with hearing loss. Hearing-impaired professionals are woefully underrepresented among the cadre of scientists currently involved in hearing and deafness research. Information was obtained by questionnaire from 190 consecutive attendees (13 through 17 years of age) at a summer program for gifted hearing-impaired adolescents regarding career goals, attitudes toward academic and extracurricular activities, educational placement, primary communication modality, and parental hearing status. A follow-up questionnaire completed by 80 of these youth, presently attending college, provided comparison data regarding type of college attended and academic major. Males were significantly more likely to select majors in mathematics and science-related disciplines. The percentage of college attendees majoring in the sciences was much lower than the percentage of high school students who aspired to a scientific career. Strategies for attracting qualified hearing-impaired students into science majors should include educational efforts directed at students, parents, and academic advisors.