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OBJECTIVE: To analyse the cause of failing voice production by a sound-producing voice prosthesis (SPVP). METHODS: The functioning of a prototype SPVP is described in a female laryngectomee before and after its sound-producing mechanism was impeded by tracheal phlegm. This assessment included: perceptual voice evaluation of read-aloud prose by an expert listener; inspection of the malfunctioning SPVP; and aero-acoustical in vivo registrations using a computer-based data acquisition system. RESULTS: Sound-producing voice prosthesis speech is higher pitched, stronger, contains less aperiodic noise and requires a lower airflow rate than the patient's regular tracheoesophageal (TE) shunt speech. Tracheal phlegm caused malfunction of the vibrating silicone lip of the SPVP by causing it to stick to its stainless steel container in an opened position, thereby reducing the SPVP to no more than a regular TE shunt valve from a functional point of view. Tracheal phonatory pressure and dynamic vocal intensity range were not affected by the functional status of the SPVP. CONCLUSIONS: To exploit the advantages an SPVP could offer female laryngectomees with an atonic or severely hypotonic pharyngoesophageal segment, the sound-producing mechanism of the SPVP needs to be less vulnerable to tracheal phlegm. [ABSTRACT FROM AUTHOR]

The one-up one-down adaptive (staircase or up-down) procedure is often used to estimate the speech recognition threshold (SRT) in speech-in-noise testing. This article provides a brief historical overview of the one-up one-down procedure in psychophysics, discussing the groundbreaking early work that is still relevant to clinical audiology and scientific research. Next, this article focuses on two aspects of the one-up one-down adaptive procedure: first, the standard error of measurement (SEM) and, second, the fluctuations in the track [i.e., the standard deviation of the signal-to-noise ratios of the stimuli within the track (SD track )]. Simulations of ideal and non-ideal listeners and experimental data are used to determine and evaluate different relationships between the parameters slope of the speech recognition function, SRT, SEM, and SD track . Hearing loss and non-ideal behavior (inattentiveness, fatigue, and giving up when the task becomes too difficult) slightly increase the average value of SD track . SD track , however, poorly discriminates between reliable and unreliable SRT estimates.

Objective: To examine whether moderate to severe congenital hearing loss (MSCHL) leads to persistent morphosyntactic problems in the written language production of adults, as it does in their spoken language production., Design: Samples of written language in Dutch were analysed for morphosyntactic correctness and syntactic complexity., Study Sample: 20 adults with MSCHL and 10 adults with normal hearing (NH)., Results: Adults with MSCHL did not differ from adults with NH in the morphosyntactic correctness and syntactic complexity of their written utterances. Within the MSCHL group, the number of morphosyntactic errors in writing was related to the degree of hearing loss in childhood., Conclusions: At the group level, MSCHL does not affect the morphosyntactic correctness of language produced in the written modality, in contrast to earlier observed effects on spoken language production. However, at the individual level, our data suggest that adults who acquired their language with more severe auditory limitations are more at risk of persistent problems with morphosyntax in written language production than adults with a lower degree of hearing loss in childhood., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Not all of the variance in speech-recognition performance of cochlear implant (CI) users can be explained by biographic and auditory factors. In normal-hearing listeners, linguistic and cognitive factors determine most of speech-in-noise performance. The current study explored specifically the influence of visually measured lexical-access ability compared with other cognitive factors on speech recognition of 24 postlingually deafened CI users. Speech-recognition performance was measured with monosyllables in quiet (consonant-vowel-consonant [CVC]), sentences-in-noise (SIN), and digit-triplets in noise (DIN). In addition to a composite variable of lexical-access ability (LA), measured with a lexical-decision test (LDT) and word-naming task, vocabulary size, working-memory capacity (Reading Span test [RSpan]), and a visual analogue of the SIN test (text reception threshold test) were measured. The DIN test was used to correct for auditory factors in SIN thresholds by taking the difference between SIN and DIN: SRT diff . Correlation analyses revealed that duration of hearing loss (dHL) was related to SIN thresholds. Better working-memory capacity was related to SIN and SRT diff scores. LDT reaction time was positively correlated with SRT diff scores. No significant relationships were found for CVC or DIN scores with the predictor variables. Regression analyses showed that together with dHL, RSpan explained 55% of the variance in SIN thresholds. When controlling for auditory performance, LA, LDT, and RSpan separately explained, together with dHL, respectively 37%, 36%, and 46% of the variance in SRT diff outcome. The results suggest that poor verbal working-memory capacity and to a lesser extent poor lexical-access ability limit speech-recognition ability in listeners with a CI.

Objectives: The aim of this study was to establish the longitudinal relationship between hearing ability in noise and psychosocial health outcomes (i.e., loneliness, anxiety, depression, distress, and somatization) in adults aged 18 to 70 years. An additional objective was to determine whether a change in hearing ability in noise over a period of 5 years was associated with a change in psychosocial functioning. Subgroup effects for a range of factors were investigated., Design: Longitudinal data of the web-based Netherlands Longitudinal Study on Hearing (NL-SH) (N = 508) were analyzed. The ability to recognize speech in noise (i.e., the speech-reception-threshold [SRTn]) was measured with an online digit triplet test at baseline and at 5-year follow-up. Psychosocial health status was assessed by online questionnaires. Multiple linear regression analyses and longitudinal statistical analyses (i.e., generalized estimating equations) were performed., Results: Poorer SRTn was associated longitudinally with more feelings of emotional and social loneliness. For participants with a high educational level, the longitudinal association between SRTn and social loneliness was significant. Changes in hearing ability and loneliness appeared significantly associated only for specific subgroups: those with stable pattern of hearing aid nonuse (increased emotional and social loneliness), who entered matrimony (increased social loneliness), and low educational level (less emotional loneliness). No significant longitudinal associations were found between hearing ability and anxiety, depression, distress, or somatization., Conclusions: Hearing ability in noise was longitudinally associated with loneliness. Decline in hearing ability in noise was related to increase in loneliness for specific subgroups of participants. One of these subgroups included participants whose hearing deteriorated over 5 years, but who continued to report nonuse of hearing aids. This is an important and alarming finding that needs further investigation.

Objective: The authors first examined the influence of moderate to severe congenital hearing impairment (CHI) on the correctness of samples of elicited spoken language. Then, the authors used this measure as an indicator of linguistic proficiency and examined its effect on performance in language reception, independent of bottom-up auditory processing., Design: In groups of adults with normal hearing (NH, n = 22), acquired hearing impairment (AHI, n = 22), and moderate to severe CHI (n = 21), the authors assessed linguistic proficiency by analyzing the morphosyntactic correctness of their spoken language production. Language reception skills were examined with a task for masked sentence recognition in the visual domain (text), at a readability level of 50%, using grammatically correct sentences and sentences with distorted morphosyntactic cues. The actual performance on the tasks was compared between groups., Results: Adults with CHI made more morphosyntactic errors in spoken language production than adults with NH, while no differences were observed between the AHI and NH group. This outcome pattern sustained when comparisons were restricted to subgroups of AHI and CHI adults, matched for current auditory speech reception abilities. The data yielded no differences between groups in performance in masked text recognition of grammatically correct sentences in a test condition in which subjects could fully take advantage of their linguistic knowledge. Also, no difference between groups was found in the sensitivity to morphosyntactic distortions when processing short masked sentences, presented visually., Conclusions: These data showed that problems with the correct use of specific morphosyntactic knowledge in spoken language production are a long-term effect of moderate to severe CHI, independent of current auditory processing abilities. However, moderate to severe CHI generally does not impede performance in masked language reception in the visual modality, as measured in this study with short, degraded sentences. Aspects of linguistic proficiency that are affected by CHI thus do not seem to play a role in masked sentence recognition in the visual modality.

Objective: The main objective was to investigate the effect of linguistic abilities (lexical-access ability and vocabulary size) on different measures of speech-in-noise recognition in normal-hearing listeners with various levels of language proficiency., Design: Speech reception thresholds (SRTs) were measured for sentences in steady-state (SRTstat) and fluctuating noise (SRTfluc), and for digit-triplets in steady-state noise (DIN). Lexical-access ability was measured with a lexical-decision test and a word-naming test. Vocabulary size was also measured. For the SRT, keyword scoring and sentence scoring were compared., Study Sample: To introduce variation in linguistic abilities, three groups of 24 young normal-hearing listeners were included: higher-educated native, lower-educated native, and higher-educated non-native listeners., Results: Lexical-access ability was most accurately measured with combined results of lexical decision and word naming. Lexical-access ability explained 60% of the variance in SRT. The effect of linguistic abilities on SRTs was up to 5.6 dB for SRTstat and 8 dB for SRTfluc. Using keyword scoring reduced this effect by approximately 1.5 dB. For DIN the effect of linguistic ability was less than 1 dB., Conclusions: Lexical-access ability is an important predictor of SRTs in normal-hearing listeners. These results are important to consider in the interpretation of speech-in-noise scores of hearing-impaired listeners.

Objectives: The first aim of the present study was to determine the change in speech recognition in noise over a period of 5 years in participants ages 18 to 70 years at baseline. The second aim was to investigate whether age, gender, educational level, the level of initial speech recognition in noise, and reported chronic conditions were associated with a change in speech recognition in noise., Design: The baseline and 5-year follow-up data of 427 participants with and without hearing impairment participating in the National Longitudinal Study on Hearing (NL-SH) were analyzed. The ability to recognize speech in noise was measured twice with the online National Hearing Test, a digit-triplet speech-in-noise test. Speech-reception-threshold in noise (SRTn) scores were calculated, corresponding to 50% speech intelligibility. Unaided SRTn scores obtained with the same transducer (headphones or loudspeakers) at both test moments were included. Changes in SRTn were calculated as a raw shift (T1 - T0) and an adjusted shift for regression towards the mean. Paired t tests and multivariable linear regression analyses were applied., Results: The mean increase (i.e., deterioration) in SRTn was 0.38-dB signal-to-noise ratio (SNR) over 5 years (p < 0.001). Results of the multivariable regression analyses showed that the age group of 50 to 59 years had a significantly larger deterioration in SRTn compared with the age group of 18 to 39 years (raw shift: beta: 0.64-dB SNR; 95% confidence interval: 0.07-1.22; p = 0.028, adjusted for initial speech recognition level - adjusted shift: beta: 0.82-dB SNR; 95% confidence interval: 0.27-1.34; p = 0.004). Gender, educational level, and the number of chronic conditions were not associated with a change in SRTn over time. No significant differences in increase of SRTn were found between the initial levels of speech recognition (i.e., good, insufficient, or poor) when taking into account the phenomenon regression towards the mean., Conclusions: The study results indicate that hearing deterioration of speech recognition in noise over 5 years can also be detected in adults ages 18 to 70 years. This rather small numeric change might represent a relevant impact on an individual's ability to understand speech in everyday life.

Objectives: The main objective was to investigate age-related differences on the listening in spatialized noise-sentences (LiSN-S) test in adults with normal audiometric thresholds in most of the speech range. A second objective was to examine the contributions of auditory, cognitive, and linguistic abilities to LiSN-S outcomes., Design: The LiSN-S test was administered to participants in an older group (M(Age) = 72.0, SD = 4.3 years) and a younger group (M(Age) = 21.7, SD = 2.6 years) with N = 26 per group. All the participants had clinically normal audiometric thresholds at frequencies up to and including 3000 Hz. The LiSN-S test yields a speech reception threshold (SRT) in each of the four speech-in-speech listening conditions that differ in the availability of voice difference cues and/or spatial separation cues. Based on these four SRTs, the scores were calculated for the talker advantage, the spatial advantage, and the total advantage as a result of both the types of cues. Additionally, the participants completed four auditory temporal-processing tests, a cognitive screening test, a vocabulary test, and tests of linguistic closure for high- and low-context sentences. The contributions of these predictor variables and measures of pure-tone hearing acuity to LiSN-S outcomes were analyzed for both the groups using regression analyses., Results: Younger listeners outperformed the older listeners on all four LiSN-S SRTs and all the three LiSN-S advantage measures. Age-related differences were larger for conditions involving the use of spatial cues. For the younger group, all LiSN-S SRTs were predicted by the measure of linguistic closure in low-context sentences; in addition, the SRT for the condition with voice difference cues but without spatial separation cues was predicted by vocabulary, and the SRT for the condition with both voice difference cues and spatial separation cues was predicted by temporal resolution at low frequencies. Vocabulary also contributed to the talker advantage in the younger group, whereas the spatial advantage was predicted by high-frequency pure-tone hearing acuity in the range 6,000 to 10,000 Hz (pure-tone average [PTA](HIGH)). For the older group, the LiSN-S SRT in the condition with neither voice difference cues nor spatial separation cues was predicted by age; their other three LiSN-S SRTs and all advantage measures were predicted by PTA(HIGH). In addition, for the older group, cognition predicted LiSN-S SRT outcomes in three of the four conditions. Measures of auditory temporal processing, linguistic abilities, or hearing acuity up to and including 4000 Hz did not predict LiSN-S outcomes in this group., Conclusions: LiSN-S outcomes were poorer for adults aged 65 years or older, even those with good audiograms, compared with younger adults and also compared with people up to the age of 60 years from a previous study. In the present study, regardless of the types of cues, auditory and cognitive interactions were reflected by the combined influences on LiSN-S outcomes of high-frequency hearing acuity and measures of linguistic and cognitive processing. The data also suggest a hierarchy in the deployment of processing resources, which would account for the observed shift from linguistic abilities in the younger group to general cognitive abilities in the older group.

The objective of this study was to determine whether hearing ability in adults is associated with medication use in general, the use of specific types of medication, or polypharmacy. In this exploratory study, data of the National Longitudinal Study on Hearing (NL-SH; n = 2,160) were used. In total, 62% of the participants reported using any medication in the past 28 days. Hearing ability in noise, as determined with an online digit-triplet speech-in-noise test, was significantly associated with (1) medication acting on the alimentary tract and metabolism (including diabetes and acid-related disorders), (2) use of calcium blockers, and (3) medication used for sensory organs., (© 2015 S. Karger AG, Basel.)

Objective: The primary objective of the study was to investigate the feasibility, reliability, and validity of the Dutch digits in noise (DIN) test for measuring speech recognition in hearing aid and cochlear implant users and compare results to the standard sentences-in-noise (SIN) test., Design: The relation between speech reception thresholds for DIN test and SIN test was analysed to determine the validity of the DIN test. As linguistic skills were expected to make different contributions in these tests, their influence was analysed., Study Sample: Participants were 12 normal-hearing listeners, 24 hearing aid users, and 24 cochlear implant users., Results: The DIN test was feasible for more participants than the SIN test. Intraclass correlation coefficients showed high reliability. The standard error of measurement was smaller for the DIN test than for the SIN test. DIN test and SIN test were highly correlated (r = 0.95 and r = 0.56 for NH+ HA and CI users respectively). In the regression analysis no significant contribution of basic linguistic skills or personal factors was found., Conclusion: In the assessment of speech recognition in noise of aided hearing-impaired listeners with hearing aids or cochlear implants, the DIN test is a feasible, reliable and valid test.

Objective: This study investigates whether the rate of decline in older persons' hearing status is associated with the rate of decrease in their psychosocial health and explores moderation by baseline hearing status, health-related factors, and sociodemographic factors., Method: Multilevel analyses were applied to data of 1,178 older participants from the Longitudinal Aging Study Amsterdam (LASA), covering 3 to 7 years of follow-up., Results: Faster decrease in speech-in-noise recognition was significantly associated with more increase in loneliness for persons with a moderate baseline speech-in-noise recognition (emotional and social loneliness) and for persons who recently lost their partner (emotional loneliness). No relationship was found with depression., Discussion: The results indicate that faster hearing decline results in more increase in loneliness in specific subgroups of older persons: in persons with an already impaired hearing and in widow(er)s. Monitoring older persons' hearing seems important and may be a relevant starting point for targeted loneliness prevention efforts., (© The Author(s) 2014.)

Aim: Despite increasing interest in visual and hearing impairment in the older population, little attention has been paid to concurrent hearing and vision loss, also known as dual sensory loss. The aim of the present study was to investigate the prevalence of comorbid hearing disability and hearing aid ownership in visually impaired older adults., Methods: In a cross-sectional survey, a self-report hearing disability screener was administered to 1396 visually impaired patients (aged ≥ 50 years) of outpatient low vision rehabilitation centers in the Netherlands and Belgium., Results: Of all participants, 44.8% (95% CI 42.2-47.5) had insufficient or poor hearing; the prevalence increased quadratically with age. Of all dual sensory impaired participants, 31.2% in the Netherlands and 55.7% in Belgium did not own hearing aids., Conclusions: The high prevalence of dual sensory loss calls for more awareness of related problems in these patients. Differences between the Netherlands and Belgium regarding hearing aid ownership might be due to different criteria used for hearing aid referral and insurance policies. For patients with dual sensory loss, specialized care implemented in low vision rehabilitation seems warranted., (© 2013 Japan Geriatrics Society.)

Objectives: To investigate the occurrence of 27 chronic medical conditions in a cohort of adults with and without hearing impairment, and to examine the association between these conditions and hearing ability., Design: The National Longitudinal Study on Hearing (NL-SH study) is a large prospective study among adults aged 18 to 70 years, conducted via the internet in the Netherlands. Hearing ability was measured with a digits-in-noise test and comorbidity was assessed through self-report., Study Sample: Cross-sectional data of 890 hearing-impaired and 975 normally-hearing adults were analyzed. Both descriptive statistics and multinomial logistic regression analyses were conducted., Results: Of the NL-SH participants with insufficient or poor hearing ability, 78.5% reported to suffer from at least one additional chronic condition. This proportion was larger than in the normally-hearing group (68.6% with one or more chronic conditions and 37.7% with two or more). After adjustment for age and gender, 'dizziness causing falling', 'diabetes' and 'arthritis types other than osteoarthritis and rheumatic arthritis' were significantly associated with poor hearing ability., Conclusions: Our results show that some previously reported associations do not only occur in older age groups, but also in younger cohorts. Comorbidity is relevant in the rehabilitation (multi-disciplinary care) and the clinical encounter.

A recent pupillometry study on adults with normal hearing indicates that the pupil response during speech perception (cognitive processing load) is strongly affected by the type of speech masker. The current study extends these results by recording the pupil response in 32 participants with hearing impairment (mean age 59 yr) while they were listening to sentences masked by fluctuating noise or a single-talker. Efforts were made to improve audibility of all sounds by means of spectral shaping. Additionally, participants performed tests measuring verbal working memory capacity, inhibition of interfering information in working memory, and linguistic closure. The results showed worse speech reception thresholds for speech masked by single-talker speech compared to fluctuating noise. In line with previous results for participants with normal hearing, the pupil response was larger when listening to speech masked by a single-talker compared to fluctuating noise. Regression analysis revealed that larger working memory capacity and better inhibition of interfering information related to better speech reception thresholds, but these variables did not account for inter-individual differences in the pupil response. In conclusion, people with hearing impairment show more cognitive load during speech processing when there is interfering speech compared to fluctuating noise.

Objectives: The first aim was to investigate whether the rate of decline in older persons' ability to recognize speech in noise over time differs across age and gender. The second aim was to determine extent demographic, health-related, environmental, and cognitive factors influence the change in speech-in-noise recognition over time., Design: Data covering 3 to 7 years of follow-up (mean: 4.9 years) of a large sample of the Longitudinal Aging Study Amsterdam were used (n = 1298; 3025 observations; baseline ages: 57 to 93 years). Hearing ability was measured by a digit triplet speech-in-noise test (SNT) yielding a speech reception threshold in noise (SRTn). Multilevel analyses were used to model the change in SRTn over time. First, interaction terms were used to test differences in rate of decline across subgroups. Second, for each of the following factors the authors determined the influence on the change in SRTn: age, gender, educational level, cardiovascular conditions, information processing speed, fluid intelligence, global cognitive functioning, smoking, and alcohol use. This was done by calculating the percentage change in Btime after adding the particular factor to the model., Results: On average, respondents' SRTn increased (i.e., deteriorated) significantly over time by 0.18 dB signal-to-noise ratio per annum. Rates were accelerated for older ages (Btime = 0.13, 0.14, 0.25, 0.27 for persons who were 57 to 65, 65 to 75, 75 to 85, and 85 to 93 years of age, respectively). Only information processing speed relevantly influenced the change in SRTn over time (17% decrease in Btime)., Conclusions: Decline in older persons' speech-in-noise recognition over time accelerated for older ages. Decline in information processing speed explained a moderate proportion of the SRTn decline. This indicates the relevance of declining cognitive abilities in the ability of older persons to recognize speech in noisy environments.

Background: Dual sensory loss (DSL) has a negative impact on health and wellbeing and its prevalence is expected to increase due to demographic aging. However, specialized care or rehabilitation programs for DSL are scarce. Until now, low vision rehabilitation does not sufficiently target concurrent impairments in vision and hearing. This study aims to 1) develop a DSL protocol (for occupational therapists working in low vision rehabilitation) which focuses on optimal use of the senses and teaches DSL patients and their communication partners to use effective communication strategies, and 2) describe the multicenter parallel randomized controlled trial (RCT) designed to test the effectiveness and cost-effectiveness of the DSL protocol., Methods/design: To develop a DSL protocol, literature was reviewed and content was discussed with professionals in eye/ear care (interviews/focus groups) and DSL patients (interviews). A pilot study was conducted to test and confirm the DSL protocol. In addition, a two-armed international multi-center RCT will evaluate the effectiveness and cost-effectiveness of the DSL protocol compared to waiting list controls, in 124 patients in low vision rehabilitation centers in the Netherlands and Belgium., Discussion: This study provides a treatment protocol for rehabilitation of DSL within low vision rehabilitation, which aims to be a valuable addition to the general low vision rehabilitation care., Trial Registration: Netherlands Trial Register (NTR) identifier: NTR2843.

Purpose: In this study, the authors assessed the influence of masking level (29% or 71% sentence perception) and test modality on the processing load during language perception as reflected by the pupil response. In addition, the authors administered a delayed cued stimulus recall test to examine whether processing load affected the encoding of the stimuli in memory., Method: Participants performed speech and text reception threshold tests, during which the pupil response was measured. In the cued recall test, the first half of correctly perceived sentences was presented, and participants were asked to complete the sentences. Reading and listening span tests of working memory capacity were presented as well., Results: Regardless of test modality, the pupil response indicated higher processing load in the 29% condition than in the 71% correct condition. Cued recall was better for the 29% condition., Conclusions: The consistent effect of masking level on the pupil response during listening and reading support the validity of the pupil response as a measure of processing load during language perception. The absent relation between pupil response and cued recall may suggest that cued recall is not directly related to processing load, as reflected by the pupil response.

The ability to recognize masked speech, commonly measured with a speech reception threshold (SRT) test, is associated with cognitive processing abilities. Two cognitive factors frequently assessed in speech recognition research are the capacity of working memory (WM), measured by means of a reading span (Rspan) or listening span (Lspan) test, and the ability to read masked text (linguistic closure), measured by the text reception threshold (TRT). The current article provides a review of recent hearing research that examined the relationship of TRT and WM span to SRTs in various maskers. Furthermore, modality differences in WM capacity assessed with the Rspan compared to the Lspan test were examined and related to speech recognition abilities in an experimental study with young adults with normal hearing (NH). Span scores were strongly associated with each other, but were higher in the auditory modality. The results of the reviewed studies suggest that TRT and WM span are related to each other, but differ in their relationships with SRT performance. In NH adults of middle age or older, both TRT and Rspan were associated with SRTs in speech maskers, whereas TRT better predicted speech recognition in fluctuating nonspeech maskers. The associations with SRTs in steady-state noise were inconclusive for both measures. WM span was positively related to benefit from contextual information in speech recognition, but better TRTs related to less interference from unrelated cues. Data for individuals with impaired hearing are limited, but larger WM span seems to give a general advantage in various listening situations.

Following previous work [Smits and Festen. (2011). J. Acoust. Soc. Am. 130, 2987-2998] involving the interpretation of speech reception threshold (SRT) data in steady-state noise, the present study considers fluctuating noise. Whereas the SIIsteady function [i.e., the speech intelligibility index (SII) against SNR in steady-state noise] can be approximated by a simple linear function going from 0 to 1 between SNR = -15 dB to +15 dB, the SIIfluc function is a function over a broader range than 30 dB and its maximum lies at a SNR higher than +15 dB. The difference in shape between the SIIsteady and SIIfluc functions has several implications. It predicts a reduction in fluctuating masker benefit (FMB), or even a negative FMB, for higher SNRs for normal-hearing listeners. Experimental data confirm this prediction. Much of the reduction in FMB for hearing-impaired listeners may be attributed to the higher SRTs in steady-state noise for these listeners.

A speech-in-noise test which uses digit triplets in steady-state speech noise was developed. The test measures primarily the auditory, or bottom-up, speech recognition abilities in noise. Digit triplets were formed by concatenating single digits spoken by a male speaker. Level corrections were made to individual digits to create a set of homogeneous digit triplets with steep speech recognition functions. The test measures the speech reception threshold (SRT) in long-term average speech-spectrum noise via a 1-up, 1-down adaptive procedure with a measurement error of 0.7 dB. One training list is needed for naive listeners. No further learning effects were observed in 24 subsequent SRT measurements. The test was validated by comparing results on the test with results on the standard sentences-in-noise test. To avoid the confounding of hearing loss, age, and linguistic skills, these measurements were performed in normal-hearing subjects with simulated hearing loss. The signals were spectrally smeared and/or low-pass filtered at varying cutoff frequencies. After correction for measurement error the correlation coefficient between SRTs measured with both tests equaled 0.96. Finally, the feasibility of the test was approved in a study where reference SRT values were gathered in a representative set of 1386 listeners over 60 years of age.

Objective: To investigate the association between hearing status, socioeconomic status and work status., Participants: Cross-sectional data of 18-64 year old participants (N=1888) from the National Longitudinal Study on Hearing (NL-SH) were used. Both normal hearing and hearing impaired subjects participated., Methods: Hearing ability in noise was measured with the National Hearing test, an online speech-in-noise test. Educational level, monthly income, being primary income earner and working status (i.e. paid employment, unemployed and looking for work, unfit for work, voluntary work, household work, being a student, or taking early retirement, and the type of work contract) were assessed with a questionnaire. Logistic regression analyses were applied., Results: Participants with poorer hearing ability were less likely to be found in the upper categories of educational level and income, having paid work > 12 hours per week, being a student, or taking early retirement. On the other hand they were more likely to look for work or to be unfit for work. No associations were found with voluntary work and household work., Discussion: Hearing ability seems to be related to both socioeconomic status and being employed. Our findings underline the importance of rehabilitation programs in audiology, aimed at supporting people with hearing impairment to help them to successfully enter or re-enter the workforce.

Objective: The goal of this review was to list and summarize work-related health programs for employees with hearing difficulties and to summarize the statistical evidence of the effectiveness of these programs., Methods: A systematic review was performed by searching the PubMed, EMBASE, PsycINFO, CINAHL, and The Cochrane Library databases for relevant citations. From 2313 unique citations retrieved from the search strategy, we included nine programs that met all inclusion criteria. The authors assessed the methodological quality of studies which evaluated the program's effectiveness, using the Downs and Black checklist., Results: Nine vocational rehabilitation programs for people with hearing difficulties were described. The programs differed in procedure, duration, setting, and content. In four studies, the effectiveness of the program was explored statistically. Measurements showed an improvement in general health (SF-36), communication strategies, and the degree of work readiness, but none of these studies included a control group, a power calculation, nor adjusted for confounding. Hence, the methodological quality to provide evidence of effectiveness was assessed as poor., Discussion: Existing vocational programs for employees with hearing difficulties provide relevant information to demonstrate how to implement the appropriate content of the programs. Future research is required to improve the strength of evidence of the effectiveness of vocational rehabilitation for workers with hearing difficulties.

In daily life, listeners use two ears to understand speech in situations which typically include reverberation and non-stationary noise. In headphone experiments, the binaural benefit for speech in noise is often expressed as the difference in speech reception threshold between diotic (N(0)S(0)) and dichotic (N(0)S(π)) conditions. This binaural advantage (BA), arising from the use of inter-aural phase differences, is about 5-6 dB in stationary noise, but may be lower in everyday conditions. In the current study, BA was measured in various combinations of noise and artificially created diotic reverberation, for normal-hearing and hearing-impaired listeners. Speech-intelligibility models were applied to quantify the combined effects. Results showed that in stationary noise, diotic reverberation did not affect BA. BA was reduced in conditions where the masker fluctuated. With additional reverberation, however, it was restored. Results for both normal-hearing and hearing-impaired listeners were accounted for by assuming that binaural unmasking is only effectively realized at low instantaneous speech-to-noise ratios (SNRs). The observed BA was related to the distribution of SNRs resulting from fluctuations, reverberation, and peripheral processing. It appears that masker fluctuations and reverberation, both relevant for everyday communication, interact in their effects on binaural unmasking and need to be considered together.

Objectives: Recent research has demonstrated that pupil dilation, a measure of mental effort (cognitive processing load), is sensitive to differences in speech intelligibility. The present study extends this outcome by examining the effects of masker type and age on the speech reception threshold (SRT) and mental effort., Design: In young and middle-aged adults, pupil dilation was measured while they performed an SRT task, in which spoken sentences were presented in stationary noise, fluctuating noise, or together with a single-talker masker. The masker levels were adjusted to achieve 50% or 84% sentence intelligibility., Results: The results show better SRTs for fluctuating noise and a single-talker masker compared with stationary noise, which replicates results of previous studies. The peak pupil dilation, reflecting mental effort, was larger in the single-interfering speaker condition compared with the other masker conditions. Remarkably, in contrast to the thresholds, no differences in peak dilation were observed between fluctuating noise and stationary noise. This effect was independent of the intelligibility level and age., Conclusions: To maintain similar intelligibility levels, participants needed more mental effort for speech perception in the presence of a single-talker masker and then with the two other types of maskers. This suggests an additive interfering effect of speech information from the single-talker masker. The dissociation between these performance and mental effort measures underlines the importance of including measurements of pupil dilation as an independent index of mental effort during speech processing in different types of noisy environments and at different intelligibility levels.

Background: Hearing impairment at the workplace, and the resulting psychosocial problems are a major health problem with substantial costs for employees, companies, and society. Therefore, it is important to develop interventions to support hearing impaired employees. The objective of this article is to describe the design of a randomized controlled trial evaluating the (cost-) effectiveness of a Vocational Enablement Protocol (VEP) compared with usual care., Methods/design: Participants will be selected with the 'Hearing and Distress Screener'. The study population will consist of 160 hearing impaired employees. The VEP intervention group will be compared with usual care. The VEP integrated care programme consists of a multidisciplinary assessment of auditory function, work demands, and personal characteristics. The goal of the intervention is to facilitate participation in work. The primary outcome measure of the study is 'need for recovery after work'. Secondary outcome measures are coping with hearing impairment, distress, self-efficacy, psychosocial workload, job control, general health status, sick leave, work productivity, and health care use. Outcome measures will be assessed by questionnaires at baseline, and 3, 6, 9, and 12 months after baseline. The economic evaluation will be performed from both a societal and a company perspective. A process evaluation will also be performed., Discussion: Interventions addressing occupational difficulties of hearing impaired employees are rare but highly needed. If the VEP integrated care programme proves to be (cost-) effective, the intervention can have an impact on the well-being of hearing impaired employees, and thereby, on the costs for the company as well for the society., Trial Registration: Netherlands Trial Register (NTR): NTR2782.

Purpose: In this research, the authors aimed to increase the analogy between Text Reception Threshold (TRT; Zekveld, George, Kramer, Goverts, & Houtgast, 2007) and Speech Reception Threshold (SRT; Plomp & Mimpen, 1979) and to examine the TRT's value in estimating cognitive abilities that are important for speech comprehension in noise., Method: The authors administered 5 TRT versions, SRT tests in stationary (SRT(STAT)) and modulated (SRT(MOD)) noise, and 2 cognitive tests: a reading span (RSpan) test for working memory capacity and a letter-digit substitution test for information-processing speed. Fifty-five adults with normal hearing (18-78 years, M = 44 years) participated. The authors examined mutual associations of the tests and their predictive value for the SRTs with correlation and linear regression analyses., Results: SRTs and TRTs were well associated, also when controlling for age. Correlations for the SRT(STAT) were generally lower than for the SRT(MOD.) The cognitive tests were correlated to the SRTs only when age was not controlled for. Age and the TRTs were the only significant predictors of SRT(MOD). SRT(STAT) was predicted by level of education and some of the TRT versions., Conclusions: TRTs and SRTs are robustly associated, nearly independent of age. The association between SRTs and RSpan is largely age dependent. The TRT test and the RSpan test measure different nonauditory components of linguistic processing relevant for speech perception in noise.

Objectives: Reduced hearing ability has been shown to influence various aspects of daily life, such as communication, psychosocial functioning, and working life. The aim of this study is to examine the association between hearing ability in noise and both sick leave and self-reported work productivity. In addition, the relationship between hearing ability and perceived health-caused limitations at work is examined., Methods: Data were collected at the baseline measurement of the Dutch "National Longitudinal Study on Hearing" and at each month during a subsequent period of 3 mo. Hearing ability was determined by means of the National Hearing Test, a speech-in-noise test over the Internet using digit triplets. The sample comprised 748 workers (385 with normal hearing ability and 363 with insufficient or poor hearing ability)., Results: Linear regression analyses revealed a significant adverse association between reduced hearing ability and self-reported absolute and differential productivity; for every dB signal-to-noise ratio (dB SNR) poorer hearing ability, self-rated absolute productivity for people experiencing little social support decreased by 0.054 points on a scale from 0 to 10 (b = -0.054; 95% confidence interval [CI] = -0.088 to -0.02). For people with less than three other chronic conditions, self-rated differential productivity also decreased significantly with decreasing hearing ability (no chronic conditions: b = -0.048 points/dB SNR on a scale from -10 to + 10, 95% CI = -0.094 to -0.001; one or two other chronic conditions: b = -0.035 points/dB SNR, 95% CI = -0.067 to -0.002). With adjustment for confounders, poorer hearing ability in noise furthermore significantly increased the odds for experiencing limitations (in the type or amount of work one could do) sometimes (odds ratio = 1.14; 95% CI = 1.07-1.21) and often to very often (odds ratio = 1.24; 95% CI = 1.05-1.45) in comparison with experiencing limitation seldom to never. A higher level of need for recovery among people with poorer hearing ability appeared to be one of the factors mediating the higher odds for sick leave of more than 5 days., Conclusion: Reduced hearing ability in noise was significantly associated with a lower self-reported absolute and differential productivity in specific cases. Also, poorer hearing increased the odds for experiencing health-caused limitations in the type or amount of work one can do. The significant relationship between hearing ability and sick leave, which was found when not adjusting for confounders, could partly be explained by a higher need for recovery among people with reduced hearing ability in noise.

It is often assumed that the benefit of hearing aids is not primarily reflected in better speech performance, but that it is reflected in less effortful listening in the aided than in the unaided condition. Before being able to assess such a hearing aid benefit the present study examined how processing load while listening to masked speech relates to inter-individual differences in cognitive abilities relevant for language processing. Pupil dilation was measured in thirty-two normal hearing participants while listening to sentences masked by fluctuating noise or interfering speech at either 50% and 84% intelligibility. Additionally, working memory capacity, inhibition of irrelevant information, and written text reception was tested. Pupil responses were larger during interfering speech as compared to fluctuating noise. This effect was independent of intelligibility level. Regression analysis revealed that high working memory capacity, better inhibition, and better text reception were related to better speech reception thresholds. Apart from a positive relation to speech recognition, better inhibition and better text reception are also positively related to larger pupil dilation in the single-talker masker conditions. We conclude that better cognitive abilities not only relate to better speech perception, but also partly explain higher processing load in complex listening conditions.

Objective: To determine the possible longitudinal relationships between hearing status and depression, and hearing status and loneliness in the older population., Design: Multiple linear regression analyses were used to assess the associations between baseline hearing and 4-year follow-up of depression, social loneliness, and emotional loneliness. Hearing was measured both by self-report and a speech-in-noise test. Each model was corrected for age, gender, hearing aid use, baseline wellbeing, and relevant confounders. Subgroup effects were tested using interaction terms., Study Sample: We used data from two waves of the Longitudinal Aging Study Amsterdam (2001-02 and 2005-06, ages 63-93). Sample sizes were 996 (self-report (SR) analyses) and 830 (speech-in-noise test (SNT) analyses)., Results: Both hearing measures showed significant adverse associations with both loneliness measures (p < 0.05). However, stratified analyses showed that these effects were restricted to specific subgroups. For instance, effects were significant only for non-hearing aid users (SR-social loneliness model) and men (SR and SNT-emotional loneliness model). No significant effects appeared for depression., Conclusions: We found significant adverse effects of poor hearing on emotional and social loneliness for specific subgroups of older persons. Future research should confirm the subgroup effects and may contribute to the development of tailored prevention and intervention programs.

Objectives: In two experiments with different subject groups, we explored the relationship between semantic context and intelligibility by examining the influence of visually presented, semantically related, and unrelated three-word text cues on perception of spoken sentences in stationary noise across a range of speech-to-noise ratios (SNRs). In addition, in Experiment (Exp) 2, we explored the relationship between individual differences in cognitive factors and the effect of the cues on speech intelligibility., Design: In Exp 1, cues had been generated by participants themselves in a previous test session (own) or by someone else (alien). These cues were either appropriate for that sentence (match) or for a different sentence (mismatch). A condition with nonword cues, generated by the experimenter, served as a control. Experimental sentences were presented at three SNRs (dB SNR) corresponding to the entirely correct repetition of 29%, 50%, or 71% of sentences (speech reception thresholds; SRTs). In Exp 2, semantically matching or mismatching cues and nonword cues were presented before sentences at SNRs corresponding to SRTs of 16% and 29%. The participants in Exp 2 also performed tests of verbal working memory capacity and the ability to read partially masked text., Results: In Exp 1, matching cues improved perception relative to the nonword and mismatching cues, with largest benefits at the SNR corresponding to 29% performance in the SRT task. Mismatching cues did not impair speech perception relative to the nonword cue condition, and no difference in the effect of own and alien matching cues was observed. In Exp 2, matching cues improved speech perception as measured using both the percentage of correctly reported words and the percentage of entirely correctly reported sentences. Mismatching cues reduced the percentage of repeated words (but not the sentence-based scores) compared with the nonword cue condition. Working memory capacity and ability to read partly masked sentences were positively associated with the number of sentences repeated entirely correctly in the mismatch condition at the 29% SNR., Conclusions: In difficult listening conditions, both relevant and irrelevant semantic context can influence speech perception in noise. High working memory capacity and good linguistic skills are associated with a greater ability to inhibit irrelevant context when uncued sentence intelligibility is around 29% correct.

Speech-in-noise-measurements are important in clinical practice and have been the subject of research for a long time. The results of these measurements are often described in terms of the speech reception threshold (SRT) and SNR loss. Using the basic concepts that underlie several models of speech recognition in steady-state noise, the present study shows that these measures are ill-defined, most importantly because the slope of the speech recognition functions for hearing-impaired listeners always decreases with hearing loss. This slope can be determined from the slope of the normal-hearing speech recognition function when the SRT for the hearing-impaired listener is known. The SII-function (i.e., the speech intelligibility index (SII) against SNR) is important and provides insights into many potential pitfalls when interpreting SRT data. Standardized SNR loss, sSNR loss, is introduced as a universal measure of hearing loss for speech in steady-state noise. Experimental data demonstrates that, unlike the SRT or SNR loss, sSNR loss is invariant to the target point chosen, the scoring method or the type of speech material.

Objectives: The aim of the present study was to evaluate the influence of age, hearing loss, and cognitive ability on the cognitive processing load during listening to speech presented in noise. Cognitive load was assessed by means of pupillometry (i.e., examination of pupil dilation), supplemented with subjective ratings., Design: Two groups of subjects participated: 38 middle-aged participants (mean age = 55 yrs) with normal hearing and 36 middle-aged participants (mean age = 61 yrs) with hearing loss. Using three Speech Reception Threshold (SRT) in stationary noise tests, we estimated the speech-to-noise ratios (SNRs) required for the correct repetition of 50%, 71%, or 84% of the sentences (SRT50%, SRT71%, and SRT84%, respectively). We examined the pupil response during listening: the peak amplitude, the peak latency, the mean dilation, and the pupil response duration. For each condition, participants rated the experienced listening effort and estimated their performance level. Participants also performed the Text Reception Threshold (TRT) test, a test of processing speed, and a word vocabulary test. Data were compared with previously published data from young participants with normal hearing., Results: Hearing loss was related to relatively poor SRTs, and higher speech intelligibility was associated with lower effort and higher performance ratings. For listeners with normal hearing, increasing age was associated with poorer TRTs and slower processing speed but with larger word vocabulary. A multivariate repeated-measures analysis of variance indicated main effects of group and SNR and an interaction effect between these factors on the pupil response. The peak latency was relatively short and the mean dilation was relatively small at low intelligibility levels for the middle-aged groups, whereas the reverse was observed for high intelligibility levels. The decrease in the pupil response as a function of increasing SNR was relatively small for the listeners with hearing loss. Spearman correlation coefficients indicated that the cognitive load was larger in listeners with better TRT performances as reflected by a longer peak latency (normal-hearing participants, SRT50% condition) and a larger peak amplitude and longer response duration (hearing-impaired participants, SRT50% and SRT84% conditions). Also, a larger word vocabulary was related to longer response duration in the SRT84% condition for the participants with normal hearing., Conclusions: The pupil response systematically increased with decreasing speech intelligibility. Ageing and hearing loss were related to less release from effort when increasing the intelligibility of speech in noise. In difficult listening conditions, these factors may induce cognitive overload relatively early or they may be associated with relatively shallow speech processing. More research is needed to elucidate the underlying mechanisms explaining these results. Better TRTs and larger word vocabulary were related to higher mental processing load across speech intelligibility levels. This indicates that utilizing linguistic ability to improve speech perception is associated with increased listening load.

This study aims to compare the use (and related costs) of different health care resources between groups of normally-hearing and hearing-impaired people. A distinction was made between hearing-related and other health care contacts. Data were collected at the baseline measurement of the national longitudinal study on hearing, and at each month during a subsequent period of six months. Hearing status was determined using an internet speech-in-noise test. The sample comprised 1295 normally-hearing and hearing-impaired subjects, aged 18-65 years. Adjusting for confounders, regression models showed that hearing-impaired respondents had significantly more contacts and higher costs for primary, secondary, and occupational care than normally-hearing respondents during the period under investigation. The differences were due to a larger number of health care contacts for which hearing impairment was the main motive to seek help. After excluding these contacts, the differences in health care use and costs between the groups were not significant. This suggests that besides hearing-related contacts, adults with hearing impairment do not make more use of health care resources than adults without hearing difficulties.

Purpose: The Speech Transmission Index (STI; Houtgast, Steeneken, & Plomp, 1980; Steeneken & Houtgast, 1980) is commonly used to quantify the adverse effects of reverberation and stationary noise on speech intelligibility for normal-hearing listeners. Duquesnoy and Plomp (1980) showed that the STI can be applied for presbycusic listeners, relating speech reception thresholds (SRTs) in various reverberant conditions to a fixed, subject-dependent STI value. The current study aims at extending their results to a wider range of hearing-impaired listeners., Method: A reverberant analogue of the SRT is presented--the speech reception reverberation threshold (SRRT)--which determines the amount of reverberation that a listener can sustain to understand 50% of the presented sentences. SRTs are performed and evaluated in terms of STI for 5 normal-hearing participants and 36 randomly selected hearing-impaired participants., Results: Results show that differences in STI between reverberant and noisy conditions are only small, equivalent to a change in speech-to-noise ratio < 1.3 dB., Conclusion: The STI appears to be a convenient, single number to quantify speech reception of hearing-impaired listeners in noise and/or reverberation, regardless of the nature of the hearing loss. In future research, the SRRT may be applied to further investigate the supposed importance of cognitive processing in reverberant listening conditions.

Objectives: The aim of this study was to evaluate the influence of sentence intelligibility on the pupil dilation response during listening. Task-induced pupil-dilation reflects explicit effortful processing load. Therefore, pupillometry can be used to examine the listening effort during speech perception in difficult listening conditions. We expected to find increasing pupil dilation as a function of decreasing speech intelligibility., Design: Thirty-eight young participants (mean age = 23 yrs, SD = 3.2 yrs) with normal hearing were included. They performed three speech reception threshold (SRT) tests in which they listened to sentences in stationary noise. A one-up-one-down, two-up-one-down, or four-up-one-down adaptive procedure was applied, resulting in the correct rehearsal of 50, 71, or 84% of the sentences (SRT(50%), SRT(71%), and SRT(84%), respectively). We examined the peak dilation amplitude, the latency of the peak dilation amplitude, and the mean pupil dilation during the processing of the speech in each of these conditions. The peak dilation amplitude and mean pupil dilation were calculated relative to the baseline pupil diameter during listening to noise alone. For each SRT condition, participants rated the experienced listening effort and estimated their performance level., Results: The signal to noise ratios (SNRs) in the SRT(50%), SRT(71%), and SRT(84%) conditions increased as a function of the speech intelligibility level. The subjective effort ratings decreased, and the estimated performance increased with increasing speech intelligibility level. Repeated measures analyses of variance indicated that peak dilation amplitude and mean pupil dilation were higher in the SRT(50%) condition as compared with the SRT(71%) and SRT(84%) conditions. The peak dilation amplitude, mean pupil dilation, and peak latency increased with decreasing SNR of the speech in noise, but no effect of noise level by itself on the baseline pupil diameter was observed. Irrespective of SNR, the pupil response was higher for incorrectly repeated sentences than for correctly repeated sentences. The analyses also indicated condition-order effects on the peak dilation amplitude and mean pupil dilatation: the pupil response was higher in the first SRT test than in the second and third tests. Within the first and third test, the baseline pupil diameter and the mean pupil dilation decreased as a function of the sentence number within the test. Spearman correlation coefficients showed no relations among the SNRs at the SRTs, subjective ratings, and the pupil response., Conclusions: The peak dilation amplitude, peak latency, and mean pupil dilation systematically increase with decreasing speech intelligibility. These results support that listening effort, as indicated by the pupil response, increases with decreasing speech intelligibility. This study indicates that pupillometry can be used to examine how listeners reach a certain performance level. Application of this technique to study listening effort can yield valuable insight into the processing resources required across listening conditions and into the factors related to interindividual differences in speech perception in noise.

The speech intelligibility index (SII) is an often used calculation method for estimating the proportion of audible speech in noise. For speech reception thresholds (SRTs), measured in normally hearing listeners using various types of stationary noise, this model predicts a fairly constant speech proportion of about 0.33, necessary for Dutch sentence intelligibility. However, when the SII model is applied for SRTs in quiet, the estimated speech proportions are often higher, and show a larger inter-subject variability, than found for speech in noise near normal speech levels [65 dB sound pressure level (SPL)]. The present model attempts to alleviate this problem by including cochlear compression. It is based on a loudness model for normally hearing and hearing-impaired listeners of Moore and Glasberg [(2004). Hear. Res. 188, 70-88]. It estimates internal excitation levels for speech and noise and then calculates the proportion of speech above noise and threshold using similar spectral weighting as used in the SII. The present model and the standard SII were used to predict SII values in quiet and in stationary noise for normally hearing and hearing-impaired listeners. The present model predicted SIIs for three listener types (normal hearing, noise-induced, and age-induced hearing loss) with markedly less variability than the standard SII.

Objective: There is a substantial lack of knowledge of the impact of reduced hearing on psychosocial functioning in adults younger than 70 yr. The aim of this study was to examine the association between hearing status and psychosocial health in adults aged between 18 and 70 yr., Design: This was a cross-sectional cohort study. Baseline data of the National Longitudinal Study on Hearing are analyzed using regression models. The cohort consisted of 1511 participants. Hearing status was determined using the National Hearing test, a recently launched speech-in-noise screening test over the Internet. We assessed self-reported psychosocial health using a set of online questionnaires., Results: Adjusting for confounding variables, significant adverse associations between hearing status and distress, somatization, depression, and loneliness are found. For every decibel signal to noise ratio (dB SNR) reduction of hearing status, both the distress and somatization scores increased by 2% [distress: b = 0.02, 95% confidence interval (CI) = 0.00 to 0.03, p = 0.03; somatization: b = 0.02, 95% CI = 0.01 to 0.04, p < 0.001]. The odds for developing moderate or severe depression increase by 5% for every dB SNR reduction in hearing (odds ratio = 1.05, 95% CI = 1.00 to 1.09, p = 0.03). The odds for developing severe or very severe loneliness significantly increase by 7% for every dB SNR reduction in hearing (odds ratio = 1.07, 95% CI = 1.02 to 1.12, p = 0.004). Different age groups exhibit different associations between hearing status and psychosocial health, with loneliness being an issue particularly in the youngest age group (18 to 30 yr). In the group of middle-aged adults (40 to 50 yr), the number of significant associations is highest., Conclusions: Hearing status is negatively associated with higher distress, depression, somatization, and loneliness in young and middle-aged adults. The associations are different in different age groups. The findings underline the need to seriously address the adverse effects of limited hearing among young and middle-aged adults both in future research and in clinical practice.

Purpose: The goal of this study was to find factors for refining candidacy criteria for bilateral hearing aid fittings. Clinical files of 1,000 consecutive hearing aid fittings were analyzed., Method: Case history, audiometric, and rehabilitation data were collected from clinical files, and an extensive questionnaire on long-term outcome measures was conducted. After at least 2 years of hearing aid use, 505 questionnaires were returned. In order to compare differences in benefits between unilateral and bilateral fittings, two subgroups were composed in which most relevant variables (age, degree of hearing loss, and audiometric asymmetry) were matched for unilateral fittings (n=212) and bilateral fittings (n=477)., Results: The bilateral group had significantly higher benefit scores than the unilateral group for detection, speech intelligibility in reverberation, and localization, but poorer scores for comfort of loud sounds. The benefit of bilateral hearing aids was not significantly related to the level of technology of the hearing aids., Conclusion: The analysis of the relation between objective parameters and the subjective outcome measures showed that candidacy for a successful bilateral fitting could not be predicted from age, maximum speech intelligibility, employment, exposure to background noise, or social activities.

The main aim of the study is to address the relationship between hearing status and need for recovery. In addition, the role of hearing status in the relationship between psychosocial work characteristics (i.e. job demands and job control) and need for recovery was assessed. The sample comprised 925 normally-hearing and hearing-impaired working adults (aged 18-65 years) participating in the National Longitudinal Study on Hearing. Hearing status was determined using the national hearing (speech-in-noise) test over the internet. Psychosocial work characteristics and need for recovery were assessed using the job content questionnaire and the Dutch questionnaire on the experience and assessment of work. Regression models revealed a significant association between hearing status and need for recovery after work, poorer hearing leading to an increasing need for recovery. Additionally, poorer hearing led to a higher odds for risky levels of need for recovery. Hearing status did not influence the significant relationship between psychosocial work characteristics (i.e. job demand and job control) and need for recovery after work. Implications for clinical practice, such as the necessity of having adequate enablement programs for this specific group of patients, are discussed.

Listening conditions in everyday life typically include a combination of reverberation and nonstationary background noise. It is well known that sentence intelligibility is adversely affected by these factors. To assess their combined effects, an approach is introduced which combines two methods of predicting speech intelligibility, the extended speech intelligibility index (ESII) and the speech transmission index. First, the effects of reverberation on nonstationary noise (i.e., reduction of masker modulations) and on speech modulations are evaluated separately. Subsequently, the ESII is applied to predict the speech reception threshold (SRT) in the masker with reduced modulations. To validate this approach, SRTs were measured for ten normal-hearing listeners, in various combinations of nonstationary noise and artificially created reverberation. After taking the characteristics of the speech corpus into account, results show that the approach accurately predicts SRTs in nonstationary noise and reverberation for normal-hearing listeners. Furthermore, it is shown that, when reverberation is present, the benefit from masker fluctuations may be substantially reduced.

It is generally recognized that poor results of speech-in-noise tests by hearing-impaired persons cannot be fully explained by the elevated pure-tone hearing threshold. Plomp has shown, among others, that an additional factor has to be taken into account, often referred to in general terms as distortion. In an attempt to specify auditory and cognitive functions which may underlie this distortion, various studies on this topic originating from Plomp's research group are reviewed, as well as other relevant studies which provide quantitative data on the correlations between various types of auditory or cognitive tests (the predictor tests) and speech-in-noise tests. The predictor variables considered include, besides the pure-tone audiogram, measures of spectral and temporal resolution, intensity difference limen, age, and some cognitive aspects. The results indicate that, by and large, these variables fall short in fully explaining the variance observed in the speech-in-noise tests. This strongly suggests that the predictor variables considered so far do not cover all sources of variance relevant for speech reception in noise.

Speech reception thresholds (SRTs) for sentences were determined in stationary and modulated background noise for two age-matched groups of normal-hearing (N = 13) and hearing-impaired listeners (N = 21). Correlations were studied between the SRT in noise and measures of auditory and nonauditory performance, after which stepwise regression analyses were performed within both groups separately. Auditory measures included the pure-tone audiogram and tests of spectral and temporal acuity. Nonauditory factors were assessed by measuring the text reception threshold (TRT), a visual analogue of the SRT, in which partially masked sentences were adaptively presented. Results indicate that, for the normal-hearing group, the variance in speech reception is mainly associated with nonauditory factors, both in stationary and in modulated noise. For the hearing-impaired group, speech reception in stationary noise is mainly related to the audiogram, even when audibility effects are accounted for. In modulated noise, both auditory (temporal acuity) and nonauditory factors (TRT) contribute to explaining interindividual differences in speech reception. Age was not a significant factor in the results. It is concluded that, under some conditions, nonauditory factors are relevant for the perception of speech in noise. Further evaluation of nonauditory factors might enable adapting the expectations from auditory rehabilitation in clinical settings.

The Speech Reception Threshold for sentences in stationary noise and in several amplitude-modulated noises was measured for 8 normal-hearing listeners, 29 sensorineural hearing-impaired listeners, and 16 normal-hearing listeners with simulated hearing loss. This approach makes it possible to determine whether the reduced benefit from masker modulations, as often observed for hearing-impaired listeners, is due to a loss of signal audibility, or due to suprathreshold deficits, such as reduced spectral and temporal resolution, which were measured in four separate psychophysical tasks. Results show that the reduced masking release can only partly be accounted for by reduced audibility, and that, when considering suprathreshold deficits, the normal effects associated with a raised presentation level should be taken into account. In this perspective, reduced spectral resolution does not appear to qualify as an actual suprathreshold deficit, while reduced temporal resolution does. Temporal resolution and age are shown to be the main factors governing masking release for speech in modulated noise, accounting for more than half of the intersubject variance. Their influence appears to be related to the processing of mainly the higher stimulus frequencies. Results based on calculations of the Speech Intelligibility Index in modulated noise confirm these conclusions.

Speech comprehension includes both bottom-up and top-down processes, and imaging studies have isolated a frontal-temporal network of brain areas active during speech perception. However, the precise role of the various areas in this network during normal speech comprehension is not yet fully understood. In the present fMRI study, the signal-to-noise ratio (SNR) of spoken sentences was varied in 144 steps, and speech intelligibility was measured independently in order to study in detail its effect on the activation of brain areas involved in speech perception. Relative to noise alone, intelligible speech in noise evoked spatially extended activation in left frontal, bilateral temporal, and medial occipital brain regions. Increasing SNR led to a sigmoid-shaped increase of activation in all areas of the frontal-temporal network. The onset of the activation with respect to SNR was similar in temporal and frontal regions, but frontal activation was found to be smaller than temporal activation at the highest SNRs. Finally, only Broca's area (BA44) showed activation to unintelligible speech presented at low SNRs. These findings demonstrate distinct roles of frontal and temporal areas in speech comprehension in that temporal regions subserve bottom-up processing of speech, whereas frontal areas are more involved in top-down supplementary mechanisms.