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Purpose: The U.S. Food and Drug Administration indications for cochlear implantation in children is currently 9 months of age and older for children with bilateral profound sensorineural hearing loss (SNHL). Studies have shown that earlier activation of a cochlear implant (CI) can lead to better spoken language outcomes. As auditory skills are a precursor to the development of spoken language, this study was developed to investigate the influence of age at CI activation on auditory skill acquisition in young children. A secondary aim was to describe the auditory skills of children implanted prior to 9 months of age as compared to children with older ages of activation. Method: Functional Listening Index (FLI) scores obtained during routine clinical visits were reviewed for 78 pediatric CI recipients with congenital bilateral profound hearing loss who were activated before 2 years of age. A linear mixed-effects model assessed the effect of age at CI activation on cumulative FLI scores over time. Results: There was a significant interaction between age at activation and chronological age at the time of evaluation, indicating that children with earlier access to sound achieved a greater number of auditory skills than those with later CI activations when measured at the same chronological age. Children activated before the age of 9 months approximated scores expected of children with typical hearing, whereas children activated between 9 and 24 months of age did not. Conclusions: Younger age at CI activation is associated with increased auditory skills over time. Children who undergo cochlear implantation and CI activation before 9 months achieve more auditory skills by 4 years of age than children who are activated at later ages. These data suggest that reducing the approved age at cochlear implantation for children with congenital bilateral profound SNHL may support optimal auditory skill acquisition.

PurposeIn a previous paper (Souza, Wright, Blackburn, Tatman, & Gallun, 2015), we explored the extent to which individuals with sensorineural hearing loss used different cues for speech identification when multiple cues were available. Specifically, some listeners placed the greatest weight on spectral cues (spectral shape and/or formant transition), whereas others relied on the temporal envelope. In the current study, we aimed to determine whether listeners who relied on temporal envelope did so because they were unable to discriminate the formant information at a level sufficient to use it for identification and the extent to which a brief discrimination test could predict cue weighting patterns.MethodParticipants were 30 older adults with bilateral sensorineural hearing loss. The first task was to label synthetic speech tokens based on the combined percept of temporal envelope rise time and formant transitions. An individual profile was derived from linear discriminant analysis of the identification responses. The second task was to discriminate differences in either temporal envelope rise time or formant transitions. The third task was to discriminate spectrotemporal modulation in a nonspeech stimulus.ResultsAll listeners were able to discriminate temporal envelope rise time at levels sufficient for the identification task. There was wide variability in the ability to discriminate formant transitions, and that ability predicted approximately one third of the variance in the identification task. There was no relationship between performance in the identification task and either amount of hearing loss or ability to discriminate nonspeech spectrotemporal modulation.ConclusionsThe data suggest that listeners who rely to a greater extent on temporal cues lack the ability to discriminate fine-grained spectral information. The fact that the amount of hearing loss was not associated with the cue profile underscores the need to characterize individual abilities in a more nuanced way than can be captured by the pure-tone audiogram.

Purpose This clinical focus article describes considerations for recommending assistive hearing technology to infants and young children who have mild bilateral or unilateral hearing loss. These conditions present special challenges compared to bilateral permanent hearing losses that are moderate to profound in their degree in that the recommendation to proceed with technology is not as clear. Conclusion Current clinical practice guidelines and protocols for pediatric hearing aid fitting recommend managing these conditions on a case-by-case basis. Descriptions of key considerations for recommending assistive hearing technology for infants and young children with mild bilateral hearing loss or unilateral hearing loss are offered herein.

Purpose The purpose of this study was to evaluate the balance of experienced adult hearing aid users with and without their hearing aids via computerized posturography. Method Computerized posturography was accomplished by employing the Sensory Organization Test (SOT) on the NeuroCom Balance Master (Natus Medical Incorporated). The SOT assessed each participant's balance and the strategy used to maintain balance in 6 progressively challenging conditions. Twenty-two adults using bilateral at-the-ear hearing aids participated in the study. All participants completed all SOT protocols with and without their hearing aids. Results No statistically significant differences in participants' balance were identified regardless of the presence or absence of their hearing aids during the SOT. Conclusions These results failed to support previous research, which indicated that amplification of auditory input could benefit balance in individuals with hearing and balance disorders. Further research utilizing randomized controlled trials is needed to resolve the disparity between the current results and those of previous studies.

Purpose This study examined the individual and combined effects of noise and reverberation on the ability of listeners with normal hearing (NH) and with bilateral cochlear implants (BCIs) to localize speech. Method Six adults with BCIs and 10 with NH participated. All subjects completed a virtual localization test in quiet and at 0-, −4-, and −8-dB signal-to-noise ratios (SNRs) in simulated anechoic and reverberant (0.2-, 0.6-, and 0.9-s RT 60 ) environments. BCI users were also tested at +8- and +4-dB SNR. A 3-word phrase was presented at 70 dB SPL from 9 simulated locations in the frontal horizontal plane (±90°), with the noise source at 0°. Results BCIs users had significantly poorer localization than listeners with NH in all conditions. BCI users' performance started to decrease at a higher SNR (+4 dB) and shorter RT 60 (0.2 s) than listeners with NH (−4 dB and 0.6 s). The combination of noise and reverberation began to degrade localization of BCI users at a higher SNR and a shorter RT 60 than listeners with NH. Conclusion The clear effect of noise and reverberation on the performance of BCI users provides information that should be useful for refining cochlear implant processing strategies and developing cochlear implant rehabilitation plans to optimize binaural benefit for BCI users in everyday listening situations.

Purpose Clinicians are regularly asked to make long-term prognoses. The aim of the current report was to present one systematic approach to doing so. A case example from a malpractice case involving a child fitted with a cochlear implant was presented. Implantation occurred at age 17 months (activation 1 month later), but due to a procedural error, the implant was not functional for 19 months. The problem was ultimately rectified, but the legal case hinged largely on whether the child would be able to make up for the lost time. Method A review of the literature on long-term outcomes in children with cochlear implants was conducted. Using 4 studies measuring outcomes 7–10 years later, outcomes were compared between children implanted at age 17–18 months and those implanted at age 36–37 months. Results Analysis suggested no potential impact on nonverbal cognitive skills. However, analysis in the areas of speech perception, word comprehension, speech intelligibility, and reading suggested that after 7–10 years, this child would potentially continue to be approximately 1–2 years behind where she might otherwise have been. Conclusions This case illustrated the possibility of deriving a long-term prognosis using a systematic examination of the existing outcomes literature. Such an approach is consistent with our mandate to engage in evidence-based practice.

Purpose Adults with hearing loss rated the accessibility of guided or docent-led art museum tours with and without hearing assistive technology (HAT). Method Nineteen individuals (average age 64 years, range 35–87 years) with acquired hearing loss participated. All participants had a bilateral hearing loss (mild to profound) using hearing aids ( n = 12), cochlear implants ( n = 5), or no technology ( n = 2). Two docents who were previously trained to modify their presentations and use clear speech led the tours. Participants experienced a tour with and without the museum's HAT and rated its effectiveness using a rating scale. The study used a pre–post test design. Results The docent-led tours with HAT were rated significantly higher ( p = .003) than the tours without HAT. Participants made several suggestions on improving museum accessibility for individuals with hearing loss. Conclusions The use of HAT during a museum tour was beneficial for individuals with hearing loss. Training docents to modify their presentations, use clear speech, and HAT improved the accessibility of docent-led tours for individuals with hearing loss.

Purpose This study measured speech perception ability in children with cochlear implants and children with typical hearing when listening across ranges of reverberation times (RTs) and speech-to-noise ratios. Method Participants listened in classroom RTs of 0.3, 0.6, and 0.9 s combined with a 21-dB range of speech-to-noise ratios. Subsets also listened in a low-reverberant audiological sound booth. Performance measures using the Bamford-Kowal-Bench Speech-in-Noise Test (Etymotic Research, Inc., 2005) were 50% correct word recognition across these acoustic conditions, with supplementary analyses of percent correct. Results Reduction in RT from 0.9 to 0.6 s benefited both groups of children. A further reduction in RT to 0.3 s provided additional benefit to the children with cochlear implants, with no further benefit or harm to those with typical hearing. Scores in the sound booth were significantly higher for the participants with implants than in the classroom. Conclusions These results support the acoustic standards of 0.6 s RT for children with typical hearing and 0.3 s RT for children with auditory issues in learning spaces (≤283 m 3 ) as specified in standards S12.60-2010/Part 1 of the American National Standards Institute /Acoustical Society of America (2010). In addition, speech perception testing in a low-reverberant booth overestimated classroom listening ability in children with cochlear implants. Supplemental Material https://doi.org/10.23641/asha.6170183

Purpose The purpose of this study was to examine the rate of progress in the 2nd implanted ear as it relates to the 1st implanted ear and to bilateral performance in adult sequential cochlear implant recipients. In addition, this study aimed to identify factors that contribute to patient outcomes. Method The authors performed a prospective longitudinal study in 21 adults who received bilateral sequential cochlear implants. Testing occurred at 6 intervals: prebilateral through 12 months postbilateral implantation. Measures evaluated speech recognition in quiet and noise, localization, and perceived benefit. Results Second ear performance was similar to 1st ear performance by 6 months postbilateral implantation. Bilateral performance was generally superior to either ear alone; however, participants with shorter 2nd ear length of deafness (30 years). All participants reported bilateral benefit. Conclusions Adult cochlear implant recipients demonstrated benefit from 2nd ear implantation for speech recognition, localization, and perceived communication function. Because performance outcomes were related to length of deafness, shorter time between surgeries may be warranted to reduce negative length-of-deafness effects. Future study may clarify the impact of other variables, such as preimplant hearing aid use, particularly for individuals with longer periods of deafness.

Purpose To determine the feasibility of using a virtual auditory test material to evaluate reverberation and noise effects on speech recognition of pediatric cochlear implant (CI) users and to compare their performance with that of children with normal hearing. Method Virtual test materials representing nonreverberant and reverberant environments were used to measure speech recognition of 7 children with CIs in quiet and in noise, and of 18 children with normal hearing in the quiet condition. Performance of CI users in noise (signal-to-noise ratio resulting in 50% performance) was compared to normative data from a previous study (Neuman, Wroblewski, Hajicek, & Rubinstein, 2010). For CI users, stimuli were sent directly to the CI speech processor via auxiliary input, whereas children with normal hearing were tested using insert phones. Results The speech recognition of children with CIs decreased significantly in the reverberant condition. There were individual differences in susceptibility to reverberation. Children with CIs also required higher signal-to-noise ratios than children with normal hearing in the reverberant condition. Conclusion Direct connect testing with reverberant test materials allows assessment of speech recognition under conditions typical of classrooms and could be useful in identifying children with CIs whose performance decreases significantly in the presence of reverberation and noise.

PurposeThe objective of this pilot study was to investigate the health-related quality of life (HRQOL) of children with unilateral hearing loss (UHL).MethodThe study was conducted in 2 stages among children age 6–17 years. In Stage 1, the authors conducted focus groups of children with UHL and their parents to elicit perceptions of how UHL affected the lives of these children. In Stage 2, a generic pediatric quality of life survey was used to measure HRQOL quantitatively in children with normal hearing, UHL, and bilateral hearing loss. Participants were recruited from the clinical and research populations of an academic otolaryngology department.ResultsThe focus groups revealed that the children with UHL experienced barriers due to their hearing loss but learned to adapt. Quantitatively, statistically significant differences between groups were not observed on the 3 main HRQOL scales (Total, Psychosocial, and Physical). Children with UHL had a significantly larger variance on the social functioning score than children with normal hearing and bilateral hearing loss.ConclusionsUHL may affect the HRQOL of children; this possibility should be included when counseling parents. However, further research is warranted to determine whether the authors' findings are generalizable to other children with UHL.

Purpose According to the frames then content (f/c) hypothesis (P. F. MacNeilage & B. L. Davis, 1990), the internal structure of syllables with consonant plus vowel structure (CV) during canonical babbling is determined primarily by production system properties related to rhythmic mandibular oscillations ( motor frames ). The purpose of this study was to evaluate whether auditory sensitivity affects the internal organization of CV syllables in infants identified in the 1st year of life with hearing loss. Method CV co-occurrence patterns were analyzed for 13 infants with varying degrees of hearing sensitivity (normal hearing [ n = 4], mild-to-moderately severe hearing loss ( n = 6), and severe-to-profound hearing loss [ n = 3]). Consonants and vowels within CV syllables were grouped according to place of articulation. Thus, an inventory of CV syllables with labial, coronal, and dorsal consonant onsets was created. Results 77% of predicted frames were confirmed above chance. Additionally, there was no association between pure-tone average and any CV co-occurrence. Finally, co-occurrences that were not predicted by the hypothesis were statistically confirmed in very few instances. Conclusions Auditory sensitivity may not influence intrasyllabic organization within CV syllables once infants begin canonical babbling, as the co-occurrences observed are primarily those predicted by the f/c hypothesis.

Purpose We propose theoretical guidelines for cochlear implant selection criteria in adults and children that emphasize the contribution of each ear to the binaural advantage. The guidelines outline options for implanting one ear only, implanting one ear plus use of a contralateral hearing aid, and implanting both ears. Method Our method for selecting the best cochlear implant or hearing aid outcome is derived from the amount of usable hearing of the patient. This approach requires the measurement of aided speech perception with each ear separately and then bilaterally. Guidelines are based on the following: (a) overall level of performance with hearing aids relative to what is expected from a cochlear implant, (b) the contributions from each ear, and (c) whether there is a binaural advantage. Conclusions Our general recommendation is to provide the patient with the best opportunity for binaural hearing. Since the guidelines put forth in this article are theoretically based, future efforts should be aimed at examining the validity of these guidelines.

Cochlear implants support deaf students' language development through the improved use of audition in the classroom. Unfortunately, the acoustics of typical classrooms greatly reduce auditory speech perception by these students. Sound-field systems can increase speech-to-noise ratios in classrooms and thus improve use of audition. These systems are used by 80% of students with cochlear implants who use an FM system in the classroom. The present study compares speech perception by 14 school-age cochlear implant recipients via 2 classroom sound-field systems, 1 wall-mounted and the other a personal, or desktop, system. Testing was conducted in 2 classroom environments, 1 noisy and reverberant (typical of many classrooms) and the other ideally quiet with reverberation of short duration. In the quiet room with low reverberation, both sound-field systems produced improved phoneme recognition, but there was no difference between the 2. In the noisy room with high reverberation, the sound-field benefits were greater, and the desktop systems provided more benefit than the wall-mounted systems.

To determine the effect of asymmetrical signal degradation on binaural speech recognition, 28 children and 14 adults were administered a sentence recognition task amidst multitalker babble. There were 3 listening conditions: (a) monaural, with mild degradation in 1 ear; (b) binaural, with mild degradation in both ears (symmetric degradation); and (c) binaural, with mild degradation in one ear and severe degradation in the other ear (asymmetric degradation). Sentences and babble were degraded digitally to simulate mild and severe cochlear hearing loss. All participants demonstrated significant binaural advantage (average of 7 dB) when listening to symmetrically degraded signals as compared to when listening monaurally. In contrast, adults and children achieved little or no binaural benefit, on average, when listening to asymmetrically degraded signals. Moreover, overall performance of the adults was significantly worse when listening to binaural asymmetrically degraded signals than when listening to monaural signals, thus demonstrating evidence of binaural interference. In contrast to our original speculations, however, children did not show an overall demonstration of binaural interference. Relative performance in the binaural-asymmetric and the monaural conditions was not influenced by which ear (right or left) received the more degraded signal.

Listeners were asked to detect amplitude modulation (AM) of a target (or signal) carrier that was presented in isolation or in the presence of an additional (masker) carrier. The signal was modulated at a rate of 10 Hz, and the masker was unmodulated or was modulated at a rate of 2, 10, or 40 Hz. Nine listeners had normal hearing, 4 had a bilateral hearing loss, and 4 had a unilateral hearing loss; those with a unilateral loss were tested in both ears. The listeners with a hearing loss had normal hearing at 1 kHz and a 30- to 40-dB loss at 4 kHz. The carrier frequencies were 984 and 3952 Hz. In one set of conditions, the lower frequency carrier was the signal and the higher frequency carrier was the masker. In the other set, the reverse was true. For the impaired ears, the carriers were presented at 70 dB SPL. For the normal ears, either the carriers were both presented at 70 dB SPL or the higher frequency carrier was reduced to 40 dB SPL to simulate the lower sensation level experienced by the impaired ears. There was considerable individual variability in the results, and there was no clear effect of hearing loss. These results suggest that a mild, presumably cochlear hearing loss does not affect the ability to process AM in one frequency region in the presence of competing AM from another region.

Experiment I investigated memory for serial order by congenitally, profoundly deaf individuals, 6–22 years old, for words presented via Cued Speech (CS) without sound. CS is a system that resolves the ambiguity inherent in speechreading through the addition of manual cues. The phonological components of CS are mouth shape, hand shape, and hand placement. Of interest was whether the recall of serial order was lower for lists of words similar in both mouth shape and hand placement, or similar in mouth shape only, or in hand placement only than for control lists designed to minimize these similarities. Deaf participants showed lower performance on the three similar lists than the control lists, suggesting that deaf individuals use the phonology of CS to support their recall. In Experiment II, the same lists were administered to two groups of hearing participants. One group, experienced producers of CS, received the CS stimuli without sound; the other group, unfamiliar with CS, received the CS stimuli audiovisually. Participants experienced with CS showed no effect of hand placement similarity, suggesting that this effect may be related to the linguistic experience of deaf participants. The recency effect was greater in the hearing group provided with sound, indicating that the traces left by auditory stimuli are perceptually more salient than those left by the visual stimuli encountered in CS.

The present investigation examined the ability of children with and without a hearing loss to correctly reproduce sequences of acoustic stimuli that varied in number, temporal spacing, and type. Forty-eight children took part in the investigation. They were divided into four groups: two groups of 6- and 7-year-old children, 12 with normal hearing and 12 with a sensorineural hearing loss; and two groups of 9- and 10-year-old children, 12 with normal hearing and 12 with a sensorineural hearing loss. All of the children completed auditory temporal sequencing tasks with verbal (/ba/ and /da/) and nonverbal (a 1-kHz pure tone and a wide band noise) acoustic stimuli. For the 6- and 7-year-old children, the results revealed a significant difference between the children with a hearing loss and their peers with normal hearing for immediate recall of verbal sequences. There were no significant differences in performance between the children with a hearing loss and their peers with normal hearing on the nonverbal sequencing tasks or on the nonverbal and verbal memory span tasks. For the 9- and 10-year-old children, the results did not show any significant differences in performance between the two groups of children for the reproduction of sequences containing more than two verbal or nonverbal elements nor for the auditory memory span task when the sequences consisted of verbal stimuli. For the recall of two verbal stimuli with a variable interstimulus interval (ISI) duration, the results showed that the children with a hearing loss experienced more difficulty than the children with normal hearing. Overall, the results indicated that on the auditory sequential organization tasks, the poorer performance of the children with a hearing loss is likely attributable to auditory perceptual processing deficits rather than to poorer short-term memory capabilities. Also, an analysis of the data revealed that the older children obtained significantly better results than the younger children on auditory sequential organization tasks.

This study was designed to evaluate long-term benefits of hearing aids in elderly individuals with hearing loss. A primary care cohort of 192 elderly, hearing-impaired veterans (mean age 72 ± 6, 97% White, 94% retired) were assessed at baseline and at 4, 8, and 12 months after hearing aid fitting. Drop-out rates at 4, 8, and 12 months were 5%, 13%, and 16%, respectively. Outcome assessments included several quality-of-life scales: Hearing Handicap Inventory in the Elderly (HHIE), Quantified Denver Scale of Communication Function (QDS), Geriatric Depression Scale (GDS), and the Short Portable Mental Status Questionnaire (SPMSQ). All quality-of-life areas improved significantly from baseline to 4-month post-hearing aid fittings ( p < 0.05). Social and emotional (HHIE), communication (QDS), and depression (GDS) benefits were sustained at 8 and 12 months, whereas cognitive changes (SPMSQ) reverted to baseline at 12 months. We conclude that hearing aids provide sustained benefits for at least a year in these elderly individuals with hearing impairment.

The purpose of this pilot study was to investigate adult Ineraid and Nucleus cochlear implant (CI) users’ perceptual accuracy for melodic and rhythmic patterns, and quality ratings for different musical instruments. Subjects were 18 postlingually deafened adults with CI experience. Evaluative measures included the Primary Measures of Music Audiation (PMMA) and a Musical Instrument Quality Rating. Performance scores on the PMMA were correlated with speech perception measures, music background, and subject characteristics. Results demonstrated a broad range of perceptual accuracy and quality ratings across subjects. On these measures, performance for temporal contrasts was better than for melodic contrasts independent of CI device. Trends in the patterns of correlations between speech and music perception suggest that particular structural elements of music are differentially accessible to cochlear implant users. Additionally, notable qualitative differences for ratings of musical instruments were observed between Nucleus and Ineraid users

Binaural loudness summation was measured using three different paradigms with 10 normally hearing and 20 bilaterally symmetrical high-frequency sensorineural hearing loss subjects. An adaptive paradigm and a loudness matching procedure measured summation at the lower and upper level of comfortable loudness and the loudness discomfort level (LDL). Monaural and binaural LDLs also were obtained with a clinical procedure designed to select maximum output of hearing aids. Stimuli for all three tasks consisted of 500- and 4000-Hz pure tones and a speech spectrum noise. Binaural summation increased with presentation level using the loudness matching procedure, with values in the 6–10 dB range. Summation decreased with level using the adaptive paradigm, and no summation was present with the clinical LDL task. The hearing-impaired subjects demonstrated binaural summation that was not significantly different from the normally hearing subjects. The results suggest that a bilaterally symmetrical sensorineural hearing loss does not affect binaural loudness summation. The monaural and binaural dynamic range widths were similar, and the LDL results suggest that binaural loudness summation may not be an important factor in selecting maximum output of hearing aids.

The amount by which individual functional gain differed from 2 cm 3 coupler gain for a single wide-band hearing aid was determined empirically for 20 hearing-impaired adults. Both occluding and non-occluding earmold fittings were evaluated. The amount of this difference accounted for by known measurement differences, such as coupler, real-ear response differences, earmold differences, and sound field pressure differences between the eardrum and hearing aid microphone location, was also established. While it was found that accounting for the known major measurement differences resulted in a reasonable estimate of median differences between measurements of functional gain and measurements of gain in a 2 cm 3 coupler, individual variability was quite high.

This study was designed to determine the effectiveness of reflex modulation (RM) audiometry in assessing the hearing sensitivity of difficult-to-test subjects. RM describes the inhibitory effect of a tone upon a subsequently elicited eyeblink reflex. Five ENT subjects were referred to the University of Kansas Andiology Clinic because of medicolegal problems or doubts regarding their hearing status. After conventional pure tone and speech audiometry had produced equivocal results, the subjects were tested by RM. The study indicates that RM is effective as an objective test of hearing for these subjects. Since RM sensitivity is not frequently dependent, it has a potential role as an adjunct to the brainstem evoked response (BSER) for testing low frequencies.

Psychoeducational data were collected from the files of 1,250 hearing-impaired children in Iowa public schools in an effort to identify educational and linguistic profiles related to different degrees of hearing loss. The files of most mildly to moderately hearing-impaired children do not reflect complete assessment of language, academic, or intellectual skills even when support services are being provided. The data reveal deficits that often are inconsistent with the reports and patterns of achievement on which the allocation of support services for hearing-impaired children have been based. The appropriateness of many of the assessment tools in use is questionable.

The Modified Rhyme Test (MRT) (Bell, Kreul, + Nixon, 1972; Kreul, Nixon, Kryter, Bell, Land, + Schubert, 1968) was used to test the word-identification ability of subjects with bilateral sensorineural hearing losses. The subjects were tested in a room with reverberation times, T, of .1 and .5 sec while listening monaurally, binaurally, aided, and unaided at various speech-to-noise ratios, S/N. A babble of 20 voices was used as a masker. Significant individual differences were found in a group of 15 subjects with various audiograms. The differences were not significant when a group was reduced to seven subjects with similar audiograms. The advantage of the binaural over monaural listening was significant and did not depend on reverberation or the use of hearing aids. Both the effects of S/N and T were significant. The effects on word-identification scores caused by a decrease in S/N from "quite" to +5 dB and by an increase in T from .1 sec to .5 sec were moderately correlated for individuals. There were individual differences in susceptibility to noise and reverberation, with subjects having asymmetrical audiograms being most susceptible. The analysis of consonant errors in noise or reverberation revealed no significant difference for the MRT. A significant difference emerged between consonant errors in the initial and final positions of the test words in both noise and reverberation.

The monosyllabic word discrimination of normal and hearing-impaired children was evaluated in situations selected to simulate acoustical conditions in current educational environments. All listeners were tested in a high-fidelity (loudspeaker-aided) condition under 12 combinations of reverberation and noise. Hearing-impaired subjects were also evaluated in the same 12 conditions while listening through a monaural hearing aid. Performance of the normal-hearing group was superior to the hearing-impaired listeners in all environments. Results suggest that classroom acoustics should be considered a critical variable in the educational achievement of children.

Perceptual patterns in rating dissimilarities among 24 CVs were investigated for a group of normal-hearing and two groups of hearing-impaired subjects (one group with flat, and one group with sloping, sensorineural losses). Stimuli were presented binaurally at most comfortable loudness level and subjects rated the 576 paired stimuli on a 1–7 equal-appearing interval scale. Ratings were submitted to individual group and combined INDSCAL analyses to describe features used by the subjects in their perception of the speech stimuli. Results revealed features such as sibilant, sonorant, plosive and place. Furthermore, normal and hearing-impaired subjects used similar features, and subjects' weightings of features were relatively independent of their audiometric configurations. Results are compared to those of previous studies.

This investigation attempted to identify listener strategies or perceptual modes that might be adopted by hearing-impaired listeners when making similarity judgments among pairs of speech sounds. Further, an attempt was made to describe the relationship between similarity judgments and auditory confusions for such listeners. Subjects provided similarity ratings and recognition responses to consonant pairs. The resulting similarity judgments were organized into a variety of similarity matrices and analyzed via multidimensional scaling and hierarchical clustering, as well as by traditional descriptive and interpretative statistics. The analyses of the similarity ratings between consonants showed that hearing-impaired listeners apply phonemic labels to the stimuli and base their ratings on these labels rather than on the unlabeled acoustic characteristics of the speech sounds. Analysis of the recognition data indicated that those consonants which are most confused are not necessarily the most conceptually similar to the listener.