Listening Difficulties Research Articles

Effects of reverberation and spatial diffuseness on the speech intelligibility of public address sounds in subway platform for young and aged people

This paper investigated how young and aged people response differently on the public address sounds in subway platform according to various reverberation and diffuseness. Both word intelligibility (WI) and listening difficulty (LD) tests were adopted as experimental method. Twelve simulated sound fields at the same position were prepared according to the combination of four different reverberation times (RT) and three different interaural cross-correlation coefficients (IACC). Auralized sounds with anechoic test words of actual station names were presented to young and aged subjects at the fixed sound pressure level. As results, LD results showed significant correlation with RT for both young and aged subjects, whereas significant correlation of WI results and RT was found only in aged subjects. Aged subjects showed worse speech intelligibility performances on public address sounds than young subjects due to their worse hearing level. RT was found as the most important factor to determine speech intelligibility for both young and aged subject, whereas aged subject showed better speech intelligibility performances with lower IACC. From the regression analysis, LD rating was estimated from the measured RT and IACC. Additionally, the effects of word familiarity, individual noise sensitivity and hearing level on the speech intelligibility were discussed.

Second Language Listening Difficulties Perceived by Low-Level Learners

The purpose was the develop a questionnaire to identify the specific listening difficulties of second language (L2) learners. Based on previous research, a questionnaire containing 31 items was developed and administered to 1,056 college freshmen. The whole sample was split randomly into two subsamples, each containing 528 cases. Exploratory factor analysis was performed to analyse the first subsample, and six factors were extracted, explaining a total of 57.1% of variance. To test the factor model, confirmatory factor analysis was conducted with the second subsample. Various fit indices were examined. The best fitting model for the data was a 23-item, six-factor model representing text, input channel and surroundings, relevance, listener, speaker, and task. Apart from the listener factor, all components are external ones and deemed to be uncontrollable by listeners. L2 learners must take an active role in listening practice to overcome L2 listening difficulties.

Asymmetries in the perception of non-native consonantal and vocalic length contrasts

How well can non-native length contrasts for vowels and for consonants be perceived and is one type more difficult than the other? Three listener groups (native Italian and German as well as advanced German learners of Italian) performed a speeded same–different task involving vocalic and consonantal length contrasts as well as segmental contrasts as controls. Phonologically, Italian, but not German, has a consonantal length contrast, while German, but not Italian, has a vocalic length contrast. Analysis of responses yielded a clear asymmetry: A non-native vowel length contrast was perceived just as well as the native consonantal length contrast. A non-native consonantal length contrast, however, was perceived poorly compared to the native vocalic length contrast: Italians showed higher sensitivity for consonantal length than German learners of Italian, who in turn were better than German non-learners. Reaction time analyses indicated that, despite displaying higher accuracy, the decision was just as difficult for learners as for non-learners, suggesting different types of difficulty for listeners with and without experience with a consonantal length contrast.

Speech Perception in Noise by Children With Cochlear Implants

Common wisdom suggests that listening in noise poses disproportionately greater difficulty for listeners with cochlear implants (CIs) than for peers with normal hearing (NH). The purpose of this study was to examine phonological, language, and cognitive skills that might help explain speech-in-noise abilities for children with CIs. Three groups of kindergartners (NH, hearing aid wearers, and CI users) were tested on speech recognition in quiet and noise and on tasks thought to underlie the abilities that fit into the domains of phonological awareness, general language, and cognitive skills. These last measures were used as predictor variables in regression analyses with speech-in-noise scores as dependent variables. Compared to children with NH, children with CIs did not perform as well on speech recognition in noise or on most other measures, including recognition in quiet. Two surprising results were that (a) noise effects were consistent across groups and (b) scores on other measures did not explain any group differences in speech recognition. Limitations of implant processing take their primary toll on recognition in quiet and account for poor speech recognition and language/phonological deficits in children with CIs. Implications are that teachers/clinicians need to teach language/phonology directly and maximize signal-to-noise levels in the classroom.

Resolving ambiguity in familiar and unfamiliar casual speech

In British English, the phrase Canada aided can sound like Canada raided if the speaker links the two vowels at the word boundary with an intrusive /r/. There are subtle phonetic differences between an onset /r/ and an intrusive /r/, however. With cross-modal priming and eye-tracking, we examine how native British English listeners and non-native (Dutch) listeners deal with the lexical ambiguity arising from this language-specific connected speech process. Together the results indicate that the presence of /r/ initially activates competing words for both listener groups; however, the native listeners rapidly exploit the phonetic cues and achieve correct lexical selection. In contrast, The Dutch-native advanced L2 listeners to English failed to recover from the /r/-induced competition, and failed to match native performance in either task. The /r/-intrusion process, which adds a phoneme to speech input, thus causes greater difficulty for L2 listeners than connected-speech processes which alter or delete phonemes.

Detection and rate discrimination of amplitude modulation in electrical hearing

Three experiments were designed to examine temporal envelope processing by cochlear implant (CI) listeners. In experiment 1, the hypothesis that listeners' modulation sensitivity would in part determine their ability to discriminate between temporal modulation rates was examined. Temporal modulation transfer functions (TMTFs) obtained in an amplitude modulation detection (AMD) task were compared to threshold functions obtained in an amplitude modulation rate discrimination (AMRD) task. Statistically significant nonlinear correlations were observed between the two measures. In experiment 2, results of loudness-balancing showed small increases in the loudness of modulated over unmodulated stimuli beyond a modulation depth of 16%. Results of experiment 3 indicated small but statistically significant effects of level-roving on the overall gain of the TMTF, but no impact of level-roving on the average shape of the TMTF across subjects. This suggested that level-roving simply increased the task difficulty for most listeners, but did not indicate increased use of intensity cues under more challenging conditions. Data obtained with one subject, however, suggested that the most sensitive listeners may derive some benefit from intensity cues in these tasks. Overall, results indicated that intensity cues did not play an important role in temporal envelope processing by the average CI listener.

The effect of hearing impairment on localization dominance for single-word stimuli.

Localization dominance (one of the phenomena of the "precedence effect") was measured in a large number of normal-hearing and hearing-impaired individuals and related to self-reported difficulties in everyday listening. The stimuli (single words) were made-up of a "lead" followed 4 ms later by a equal-level "lag" from a different direction. The stimuli were presented from a circular ring of loudspeakers, either in quiet or in a background of spatially diffuse babble. Listeners were required to identify the loudspeaker from which they heard the sound. Localization dominance was quantified by the weighting factor c [B.G. Shinn-Cunningham et al., J. Acoust. Soc. Am. 93, 2923-2932 (1993)]. The results demonstrated large individual differences: Some listeners showed near-perfect localization dominance (c near 1) but many showed a much reduced effect. Two-thirds (64/93) of the listeners gave a value of c of at least 0.75. There was a significant correlation with hearing loss, such that better hearing listeners showed better localization dominance. One of the items of the self-report questionnaire ("Do you have the impression of sounds being exactly where you would expect them to be?") showed a significant correlation with the experimental results. This suggests that reductions in localization dominance may affect everyday auditory perception.

Update on Bone-Anchored Hearing Aids in Pediatric Patients With Profound Unilateral Sensorineural Hearing Loss

To evaluate the use of bone-anchored hearing aids (Bahas) in children with single-sided deafness. Retrospective 3-year chart review. Arkansas Children's Hospital, Little Rock, pediatric hospital serving children from birth to 21 years of age. The study included 23 children (14 girls and 9 boys) with single-sided deafness (mean age, 12.6 years; age range, 6-19 years). Two-stage Baha surgery with 6-month osseointegration was performed on children 5 years and older at a single institution. The Baha processor was placed 2 weeks after the second-stage surgery. Results of the Hearing in Noise Test (HINT) and the Children's Home Inventory for Listening Difficulties (CHILD) questionnaires were compared before and after Baha activation in children with profound unilateral sensorineural hearing loss. Preimplant mean HINT scores at speech-noise ratios of 0, +5, and +10 dB were 42%, 76%, and 95%, respectively. Postimplant mean HINT scores improved to mean speech-noise ratios of 82%, 97%, and 99% at 0, 5, and 10 dB, respectively. The CHILD scores also improved from mean preimplant ratings of 4.49 and 4.60 for patients and parents, respectively, to postimplant ratings of 6.90 and 7.10. Both teenagers (n = 15) and children younger than 13 years (n = 7) demonstrated improved HINT and CHILD scores. The complication rate was 17%. Bone-anchored hearing aids are a durable treatment option that can achieve noticeable improvements in hearing in noise and in listening difficulties in children with profound unilateral sensorineural hearing loss.

Bone-Anchored Hearing Aids for Unilateral Hearing Loss in Teenagers

Outside of classroom interventions, treatment for unilateral hearing loss in children has been limited. The purpose of this clinical capsule was to report on follow-up of a case series of teenage patients who received bone-anchored hearing aids (BAHAs) to compensate for single-sided deafness. Three patients (2 boys, 1 girl) 16 to 18 years of age with a profound sensorineural hearing loss in 1 ear. Bone-anchored hearing aid surgery was performed using a 2-stage surgical procedure separated by a 6-month period for proper osseointegration. Patients were fitted with a BAHA Divino (Cochlear Bone Anchored Solutions, Molnlycke, Sweden) 2 weeks after the second-stage surgery. Results of the hearing-in-noise test (HINT), with speech stimuli at 0 degree azimuth and noise at 180 degrees azimuth, as well as results of the Children's Home Inventory for Listening Difficulties (CHILD) questionnaire, completed by both the patient and a parent. The HINT and CHILD were performed before and after BAHA fitting. There were higher CHILD scores postimplant, indicating improved child and parent satisfaction. Better results on the HINT postimplant indicated an improved ability to understand speech in noise. The BAHA appeared to be of benefit to these teenage patients with unilateral hearing loss.

The effect of hearing impairment on the identification of speech that is modulated synchronously or asynchronously across frequency

This study investigated the effect of mild-to-moderate sensorineural hearing loss on the ability to identify speech in noise for vowel-consonant-vowel tokens that were either unprocessed, amplitude modulated synchronously across frequency, or amplitude modulated asynchronously across frequency. One goal of the study was to determine whether hearing-impaired listeners have a particular deficit in the ability to integrate asynchronous spectral information in the perception of speech. Speech tokens were presented at a high, fixed sound level and the level of a speech-shaped noise was changed adaptively to estimate the masked speech identification threshold. The performance of the hearing-impaired listeners was generally worse than that of the normal-hearing listeners, but the impaired listeners showed particularly poor performance in the synchronous modulation condition. This finding suggests that integration of asynchronous spectral information does not pose a particular difficulty for hearing-impaired listeners with mild/moderate hearing losses. Results are discussed in terms of common mechanisms that might account for poor speech identification performance of hearing-impaired listeners when either the masking noise or the speech is synchronously modulated.

Assessing Auditory Milestones in Children

Assessing Auditory Milestones in Children

Speech listening difficulty and word intelligibility of aged listeners in reverberant sound fields

The experiment was performed to present the effect of hearing loss on listening difficulty and word intelligibility with aged subjects in same sound fields of the previous work [M. Morimoto et al., J. Acoust. Soc. Am. 108, 2633 (2000)], and the result of this experiment is compared with this previous work. In the test, both the listening difficulty and the intelligibility were assessed using word lists based on word familiarity. The results demonstrate that (1) The relation between listening difficulties of young subjects and aged subjects is highly correlated. The range of scores of aged subjects is half of that of young subjects. (2) This word intelligibility score of young subjects is higher than that of aged subjects by 25% in all conditions. This result is the same as the previous work [H. Sato et al., J. Acoust. Soc. Am. 108, 2634 (2000)]. (3) The relation between listening difficulty and word intelligibility shows the same tendency for the both aged and young subjects. (4) Hearing level has a good correlation with listening difficulty and word intelligibility scores.

A cognitive perspective on language learners' listening comprehension problems

In this article, I offer a cognitive perspective on the comprehension problems of second language listeners. I do this by identifying real-time listening difficulties faced by a group of English as a second language (ESL) learners and examining these difficulties within the three-phase model of language comprehension proposed by Anderson (1995, Cognitive Psychology and its Implications, 4th Edition. Freeman, New York). Data were elicited from learners' self-reports through the procedures of learner diaries, small group interviews and immediate retrospective verbalisations. My analysis showed 10 problems which occurred during the cognitive processing phases of perception, parsing and utilisation. Five problems were linked to word recognition and attention failure during perceptual processing. There were also problems related to inefficient parsing and failure to utilise the mental representations of parsed input. A comparison of two groups of learners with different listening abilities showed some similarities in the difficulties experienced, but low ability listeners had more problems with low-level processing. In the last part of the article, I highlight the benefits of researching real-time cognitive constraints during listening and obtaining data through learners' introspection, and offer some practical suggestions for helping learners become better listeners.

Factors affecting vowel identification in hearing-impaired listeners

Vowel identification generally poses little difficulty for listeners with mild to moderate hearing impairment despite evidence for poorer frequency resolution compared to normal-hearing listeners. Normal-hearing listeners use formant movement and duration cues as well as spectral target cues to identify vowels. This study examines use of formant movement and duration cues by hearing-impaired listeners. Sets of very natural-sounding vowel stimuli with and without formant movement cues (dynamic and static) and with and without duration cues (appropriate and fixed) were made with a new speech resynthesis technique [H. Kawahara, Proc. ICASSP, 1–4 (1997)] using vowels produced by male and female talkers in /dVd/ context. Two groups of young normal-hearing listeners, one with simulated hearing loss typical of 70 year-old males and one control group, displayed no difference in overall vowel identification scores. Both groups obtained significant benefit from tokens containing formant movement cues. Duration was not as effective a cue for vowel identification as formant movement. Results for elderly hearing-impaired and elderly normal-hearing listeners will be presented, and the impact of talker variability upon vowel identification will be discussed. [Work supported by NIH-NIDCD 02229.]

Characterizing the influence of native language experience on adult speech perception.

Previous cross-language research has indicated that some speech contrasts present greater perceptual difficulty for adult non-native listeners than others do. It has been hypothesized that phonemic, phonetic, and acoustic factors contribute to this variability. Two experiments were conducted to evaluate systematically the role of phonemic status and phonetic familiarity in the perception of non-native speech contrasts and to test predictions derived from a model proposed by Best, McRoberts, and Sithole (1988). Experiment 1 showed that perception of an unfamiliar phonetic contrast was not less difficult for subjects who had experience with an analogous phonemic distinction in their native language than for subjects without such analogous experience. These results suggest that substantive phonetic experience influences the perception of non-native contrasts, and thus should contribute to a conceptualization of native language-processing skills. In Experiment 2, English listeners' perception of two related nonphonemic place contrasts was not consistently different as had been expected on the basis of phonetic familiarity. A clear order effect in the perceptual data suggests that interactions between different perceptual assimilation patterns or acoustic properties of the two contrasts, or interactions involving both of these factors, underlie the perception of the two contrasts in this experiment. It was concluded that both phonetic familiarity and acoustic factors are potentially important to the explanation of variability in perception of nonphonemic contrasts. The explanation of how linguistic experience shapes speech perception will require characterizing the relative contribution of these factors, as well as other factors, including individual differences and variables that influence a listener's orientation to speech stimuli.

Speech Recognition Ability of Children with Unilateral Sensorineural Hearing Loss as a Function of Amplification, Speech Stimuli and Listening Condition*

The purpose of this investigation was to examine three types of audiological recommendations [unaided, CROS (contralateral routing of signals) and personal FM system] and their impact upon speech recognition ability of children with unilateral sensorineural hearing loss. Each of these recommendations was tested under three listening conditions encountered in a classroom [monaural direct (MD), monaural indirect (MI), midline signal/omnidirectional noise (MS/ON)] with two types of speech materials (Nonsense Syllable Test and an American English adaptation on the Bamford-Kowal-Bench Sentence Lists). These experimental conditions were simulated in a classroom, recorded on audiotape, and played back to subjects under headphones to control such factors as signal-to-noise ratio, earmold fit, and head shadow effects. Six school-age children with unilateral hearing losses between 56 and greater than 120 dB HL (PTA) were evaluated using a repeated measures design. The children experienced the most listening difficulty in the MI condition when they were unaided. The CROS aid improved speech recognition in this condition but degraded speech recognition in the MD condition. The FM system was the only audiological recommendation to produce uniformly high speech recognition scores across all listening conditions with both types of speech materials. Implications for the audiological management of unilaterally hearing-impaired children in the classroom are discussed.

Everyday Sound Perception and Aging

Age related hearing loss is extensively documented in both longitudinal and cross-sectional studies but there are no direct studies of the ability of older persons to perceive everyday sounds. There is evidence suggesting some impairment. Vanderveer (1979) observed that older listeners had difficulty interpreting environmental sounds but did not report any performance data. Demands imposed by the stimulus properties of this type of sound and by the perceptual and cognitive processes found to mediate perception of this sound in college-aged listeners may present difficulty for older listeners. Forty-seven members of a retired organization were given a subset of sounds that had been used in previous identification studies. Identification data for the same set of sounds had been previously obtained from high school and college students (Ballas, Dick, & Groshek, 1987). The ability of the aged group to identify this set of sounds was not significantly different from the ability of a student group. In fact, uncertainties were closely matched except for a few sounds. Directions for future research are discussed.

Central Auditory Processing Through the Looking Glass: A Critical Look at Diagnosis and Management

Central auditory processing (CAP) disordered language impaired (LI) children have listening, language and learning difficulties that come to the attention of both the audiologist and the speech-language pathologist. Traditionally, the former has been resposible primarly for CAP diagnosis and the latter has been assigned the task of remediation. In this article, the contributions of both professionals to the diagnosis and management of this population are discussed. The variables that can compound the evaluative and therapeutic efforts of audiologists and speech-language pathologists are examined and used to show that shared professional perspectives are the most efficacious ones.