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.     

Predictive factors for speech perception in patients with cochlear implant

Cochlear implant therapy is an epoch-making advance in artificial sensory organ transplants, but the positive effects on speech perception vary. Quantification theory type I, a multivariate analysis, was used to determine predictive factors for speech perception in patients with cochlear implants. Fifty-one postlingual deaf adults (18 male and 33 female, mean age, 53.4, mean duration of deafness, 8.6 years) were tested for speech perception three or more months after a Nucleus 22 channels cochlear implant. The cause of deafness in nine patients was labyrinthitis, ototoxicity in five, meningitis in three and unknown in the remaining 34. Speech perception was measured by vowel, consonant and word recognition using a live voice, and monosyllable, word and sentence recognition using a videodisc. All tests were administered in a sound only condition. Results of the univariate analysis indicated that age at implantation was correlated with monosyllable recognition, and duration of deafness was correlated with live voice word recognition. Residual hearing and coding strategy were both correlated with all outcome measures. The multivariate analysis revealed that coding strategy, duration of deafness, residual hearing and the number of electrodes were significant predictors of live voice word recognition in that order.     

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.     

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.     

Speech perception and speech comprehension investigations of pre-term newborns and high-risk neonates of pre-school age

The purpose of this study is to establish whether there is any connection between neonatal morbidity and speech perception and comprehension in children of pre-school age who have previously been treated as newborn infants in an intensive care unit. The test applied is a method invented in Hungary for the analysis of global hearing, speech perception and comprehension. The authors summarize the results of their follow-up studies of 52 children with respiratory disorders as newborns, some of whom were born as pre-term and some as full-term newborns with asphyxia. The children have been put into three groups according to their maturity and their birthweight. Newborns with hearing loss and mental retardation were excluded from this study. Of the various neonatal factors the results show: complications of delivery, birthweight, hypoxia, persistent ductus arteriosus, duration of ventilation and complications of respiratory treatment are found to be correlated to perception and comprehension. Incidences of poor achievement obtained in the most characteristic subtests have been compared among the different groups of newborns. The intelligence level of pre-school children is found to be closely correlated to speech perception and comprehension.     

Hearing handicap--an addition to audiometric hearing loss. Results of an exploratory study of auditory communication disorders in the elderly

Hearing problems in elderly patients cannot be evaluated completely with conventional audiological tests in most cases. Two hundred and one subjects aged 60 years or more complaining of hearing problems were studied. The following tests were employed: pure-tone audiometry, the "Basler Satztest" (a German version of the SPIN-test assessing speech perception in noise), and a German version of a "Hearing Handicap Inventory for the Elderly" (HHIE). These latter versions were developed in our institution. An auditory handicap was found in one-third of subjects with mild hearing losses (PTA < 30 dB; n = 135) and in two-thirds of subjects with greater hearing losses (PTA > and = 30 dB; n = 65). The relatively weak correlations of the pure-tone audiogram (r = 0.49) or speech audiometry (r = 0.41) with HHIE indicate that more than 50% of the variance of the hearing handicap was due to non-audiologic factors. For this reason, we recommend that the handicap questionnaire be added to the audiometric evaluation.     

Use of the speech pattern audiometer and the electropalatograph to explore the speech production/perception relationship in a profoundly deaf child

The use of electropalatography (EPG) in the teaching of new speech skills to deaf speakers, is not widely researched. Whether these skills can be maintained, or whether they can become fully automatic, without enough speech perception to enable auditory self-monitoring is therefore unclear. Most approaches to increasing speech intelligibility in deaf speakers, rightly, place an emphasis on maximizing residual hearing and listening skills. However, a small amount of evidence exists which suggests that speech production can aid speech perception. This research aimed to measure change in speech perception, through use of the speech pattern audiometer (SPA), whilst working on speech production with the electropalatograph. Intervention took place over a year. The issues of maintenance and generalization are discussed.     

Audiologic evaluation of deaf children

This paper describes an audiologic test battery for hearing-impaired children which includes otoscopic examination, tympanometry, pure-tone audiometry, speech perception testing, and hearing aid evaluation. Several of the procedures and modifications to apparatus have been developed specifically for use with deaf children. Clinical data are presented from 160 hearing-impaired children (age range three-16 years). Eighteen percent of their ears were found to contain excessive cerumen and to require ear canal irrigation. The incidence of abnormal tympanograms was high for young children but decreased with increasing age. A simple auditory speech perception test designed for use with both severely and profoundly deaf children is described, which provides for evaluation of a child's ability to recognize words, categorize them into stress patterns, or both. The children's word recognition and word categorization scores were found to relate to their audiometric averages. The overall test battery is easy to administer and also is efficient, in that considerable audiologic information can be obtained quickly.     

Auditory perception with level-dependent hearing protectors. The effects of age and hearing loss

Auditory perception with hearing protectors was assessed in three groups of subjects, two with normal hearing, but differing in age, and one with moderate bilateral sensorineural hearing loss. Individuals were tested with the ears unoccluded, and fitted with each of two level-dependent ear muffs and their conventional level-independent counterparts. One of the former devices provided limited amplification. In each of these five ear conditions, the threshold of audibility for one-third octave noise bands centered at 500, 1,000, 2,000 and 4,000 Hz, consonant discrimination, and word recognition were measured in quiet and in a continuous impulse noise background. The results showed that the attenuation of sounds (i.e. the difference between protected and unoccluded thresholds) in quiet did not vary as a function of age or hearing loss for any of the four protectors. In noise, the difference between protected and unoccluded listening was close to zero, as long as hearing was normal. With hearing loss as a factor, there was a significant increment in the protected threshold, the amount determined by the device. Word recognition in quiet was adversely affected in normal-hearing listeners by the three attenuating devices but improved in noise relative to unoccluded listening. Amplification had a deleterious effect for both consonant discrimination and word recognition in noise. In hearing-impaired listeners, speech perception was impeded by all four muffs but less so in quiet with limited amplification.     

Point-light facial displays enhance comprehension of speech in noise

Seeing a talker's face can improve the perception of speech in noise. There is little known about which characteristics of the face are useful for enhancing the degraded signal. In this study, a point-light technique was employed to help isolate the salient kinematic aspects of a visible articulating face. In this technique, fluorescent dots were arranged on the lips, teeth, tongue, cheeks, and jaw of an actor. The actor was videotaped speaking in the dark, so that when shown to observers, only the moving dots were seen. To test whether these reduced images could contribute to the perception of degraded speech, noise-embedded sentences were dubbed with the point-light images at various signal-to-noise ratios. It was found that these images could significantly improve comprehension for adults with normal hearing and that the images became more effective as participants gained experience with the stimuli. These results have implications for uncovering salient visual speech information as well as in the development of telecommunication systems for listeners who are hearing impaired.     

Does audiovisual speech offer a fountain of youth for old ears? An event-related brain potential study of age differences in audiovisual speech perception.

The current study addressed the question whether audiovisual (AV) speech can improve speech perception in older and younger adults in a noisy environment. Event-related potentials (ERPs) were recorded to investigate age-related differences in the processes underlying AV speech perception. Participants performed an object categorization task in three conditions, namely auditory-only (A), visual-only (V), and AVspeech. Both age groups revealed an equivalent behavioral AVspeech benefit over unisensory trials. ERP analyses revealed an amplitude reduction of the auditory P1 and N1 on AVspeech trials relative to the summed unisensory (A + V) response in both age groups. These amplitude reductions are interpreted as an indication of multisensory efficiency as fewer neural resources were recruited to achieve better performance. Of interest, the observed P1 amplitude reduction was larger in older adults. Younger and older adults also showed an earlier auditory N1 in AVspeech relative to A and A + V trials, an effect that was again greater in the older adults. The degree of multisensory latency shift was predicted by basic auditory functioning (i.e., higher hearing thresholds were associated with larger latency shifts) in both age groups. Together, the results show that AV speech processing is not only intact in older adults, but that the facilitation of neural responses occurs earlier in and to a greater extent than in younger adults. Thus, older adults appear to benefit more from additional visual speech cues than younger adults, possibly to compensate for more impoverished unisensory inputs because of sensory aging. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

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.     

Reflections on the development of speech perception.

The literature on the role of infant–adult comparisons in developmental accounts of speech perception is reviewed, and methodological problems associated with such comparisons are delineated. It is argued that the data that are appropriate for the evaluation of categorical perception in infancy are unavailable. Moreover, the view that language experience operates to eliminate discriminative abilities once present rather than to add abilities once absent is without clear-cut support. The serious confounding of age and method of testing casts doubt on current developmental accounts of speech perception based on comparisons of infant and adult. (French abstract) (87 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age-related changes on a children's test of sensory-level speech perception capacity

Normative data, as a function of age, were obtained on a test designed to assess sensory-level speech perception capacity, the Three-Interval Forced-Choice Test of Speech Pattern Contrast Perception, otherwise known as THRIFTSPAC (or THRIFT for short). Performance under the input modalities of hearing alone, speech-reading alone, and the two combined was measured in 44 normally developing children between the ages of 5 years 7 months and 10 years 9 months. Results revealed that within each condition there were significant influences of age on performance for children below age 7 years. These changes appeared to be related to cognitive and, possibly, to phonological development. Implications for the clinical implementation of THRIFT are discussed.     

Activation of auditory cortex during silent lipreading

Watching a speaker's lips during face-to-face conversation (lipreading) markedly improves speech perception, particularly in noisy conditions. With functional magnetic resonance imaging it was found that these linguistic visual cues are sufficient to activate auditory cortex in normal hearing individuals in the absence of auditory speech sounds. Two further experiments suggest that these auditory cortical areas are not engaged when an individual is viewing nonlinguistic facial movements but appear to be activated by silent meaningless speechlike movements (pseudospeech). This supports psycholinguistic evidence that seen speech influences the perception of heard speech at a prelexical stage.     

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.     

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.     

Recognition of multiply degraded speech by young and elderly listeners

This study investigated the hypothesis that age effects exert an increased influence on speech recognition performance as the number of acoustic degradations of the speech signal increases. Four groups participated: young listeners with normal hearing, elderly listeners with normal hearing, young listeners with hearing loss, and elderly listeners with hearing loss. Recognition was assessed for sentence materials degraded by noise, reverberation, or time compression, either in isolation or in binary combinations. Performance scores were converted to an equivalent signal-to-noise ratio index to facilitate direct comparison of the effects of different forms of stimulus degradation. Age effects were observed primarily in multiple degradation conditions featuring time compression of the stimuli. These results are discussed in terms of a postulated change in functional signal-to-noise ratio with increasing age.     

Antibody-directed enzyme prodrug therapy: pharmacokinetics and plasma levels of prodrug and drug in a phase I clinical trial

OBJECTIVE: The objective of the study was to determine the major factors that underlie auditory/audiological performance measures in an elderly population, with particular emphasis on finding those factors responsible for speech understanding under specific conditions of interference. DESIGN: Audiological status and auditory performance of a group of elderly (60- to 81-yr-old) and normal-hearing young (18- to 30-yr-old) individuals was determined through a test battery. When present, the hearing loss of elderly subjects was symmetrical in the two ears and, at most, moderate. The battery included tests of speech intelligibility on the word and sentence levels, with and without the presence of interfering speech. In addition to pure-tone and speech reception thresholds, perception of spectrally or temporally distorted speech as well as auditory resolution of frequency, time, and space were tested. Two tests received special consideration: the Speech Perception In Noise Test and the Modified Rhyme Reverberation Test. Taking the overall results as well as various subsets of the results, principal component analyses were conducted to identify major factors underlying auditory performance. RESULTS: The factors extracted by the principal component analyses present a portrayal of the auditory performance profile in which effects of interference, high-frequency hearing, and basic auditory function play a major role. Interference factors include general susceptibility to noise as well as segregation of concurrent speech sounds on the basis of temporal dissimilarities and spatial separation. Comparison of factors extracted from various subsets of tests indicate that factors underlying the decline of the "cocktail party effect" in the elderly are addressed mostly by tests specifically designed to assess speech understanding in spatially distributed babble or in a reverberant environment. CONCLUSIONS: Factor analysis of test measures obtained from a group of elderly individuals with normal hearing or mild-to-moderate hearing loss led to two main findings. First, it portrayed hearing loss as a component of different factors rather than as a factor on its own. Second, the independence of measures of speech understanding in babble or reverberation from other measures suggests that such tests should become an integral part of audiological test batteries designed to assess auditory functions in aging.