The word-with-noise test: development, validation and reference values. / Teste de palavras no ruído: desenvolvimento, validação e valores de referência.

PURPOSE: To propose an instrument for assessing speech recognition in the presence of competing noise. To define its application strategy for use in clinical practice. To obtain evidence of criterion validity and present reference values. METHODS: The study was conducted in three stages: Organization of the material comprising the Word-with-Noise Test (Stage 1); Definition of the instrument's application strategy (Stage 2); Investigation of criterion validity and definition of reference values for the test (Stage 3) through the evaluation of 50 normal-hearing adult subjects and 12 subjects with hearing loss. RESULTS: The Word-with-Noise Test consists of lists of monosyllabic and disyllabic words and speech spectrum noise (Stage 1). The application strategy for the test was defined as the determination of the Speech Recognition Threshold with a fixed noise level at 55 dBHL (Stage 2). Regarding criterion validity, the instrument demonstrated adequate ability to distinguish between normal-hearing subjects and subjects with hearing loss (Stage 3). Reference values for the test were established as cut-off points expressed in terms of signal-to-noise ratio: 1.47 dB for the monosyllabic stimulus and -2.02 dB for the disyllabic stimulus. Conclusion: The Word-with-Noise Test proved to be quick to administer and interpret, making it a useful tool in audiological clinical practice. Furthermore, it showed satisfactory evidence of criterion validity, with established reference values.

OBJETIVO: Propor um instrumento para a avaliação do reconhecimento de fala na presença de ruído competitivo. Definir sua estratégia de aplicação, para ser aplicado na rotina clínica. Obter evidências de validade de critério e apresentar seus valores de referência. MÉTODO: Estudo realizado em três etapas: Organização do material que compôs o Teste de Palavras no Ruído (Etapa 1); Definição da estratégia de aplicação do instrumento (Etapa 2); Investigação da validade de critério e definição dos valores de referência para o teste (Etapa 3), por meio da avaliação de 50 sujeitos adultos normo-ouvintes e 12 sujeitos com perda auditiva. RESULTADOS: O Teste de Palavras no Ruído é composto por listas de vocábulos mono e dissilábicos e um ruído com espectro de fala (Etapa 1). Foi definida como estratégia de aplicação do teste, a realização do Limiar de Reconhecimento de Fala com ruído fixo em 55 dBNA (Etapa 2). Quanto à validade de critério, o instrumento apresentou adequada capacidade de distinção entre os sujeitos normo-ouvintes e os sujeitos com perda auditiva (Etapa 3). Foram definidos como valores de referência para o teste, os pontos de corte expressos em relação sinal/ruído de 1,47 dB para o estímulo monossilábico e de -2,02 dB para o dissilábico. CONCLUSÃO: O Teste de Palavras no Ruído demonstrou ser rápido e de fácil aplicação e interpretação dos resultados, podendo ser uma ferramenta útil a ser utilizada na rotina clínica audiológica. Além disso, apresentou evidências satisfatórias de validade de critério, com valores de referência estabelecidos.

A novel approach for estimating initial sound level for speech reception threshold test.

BACKGROUND: The speech reception threshold (SRT), synonymous with the speech recognition threshold, denotes the minimum hearing level required for an individual to discern 50% of presented speech material. This threshold is measured independently in each ear with a repetitive up-down adjustment of stimulus level starting from the initial SRT value derived from pure tone thresholds (PTTs), measured via pure-tone audiometry (PTA). However, repetitive adjustments in the test contributes to increased fatigue for both patients and audiologists, compromising the reliability of the hearing tests. OBJECTIVE: Determining the first (initial) sound level closer to the finally determined SRT value, is important to reduce the number of repetitions. The existing method to determine the initial sound level is to average the PTTs called pure tone average (PTAv). METHODS: We propose a novel method using a machine learning approach to estimate a more optimal initial sound level for the SRT test. Specifically, a convolutional neural network with 1-dimensional filters (1D CNN) was implemented to predict a superior initial level than the conventional methods. RESULTS: Our approach produced a reduction of 37.92% in the difference between the initial stimulus level and the final SRT value. CONCLUSIONS: This outcome substantiates that our approach can reduce the repetitions for finding the final SRT, and, as the result, the hearing test time can be reduced.

Development of the Children's English and Spanish Speech Recognition Test: Psychometric Properties, Feasibility, Reliability, and Normative Data.

OBJECTIVES: The Children's English and Spanish Speech Recognition (ChEgSS) test is a computer-based tool for assessing closed-set word recognition in English and in Spanish, with a masker that is either speech-shaped noise or competing speech. The present study was conducted to (1) characterize the psychometric properties of the ChEgSS test, (2) evaluate feasibility and reliability for a large cohort of Spanish/English bilingual children with normal hearing, and (3) establish normative data. DESIGN: Three experiments were conducted to evaluate speech perception in children (4-17 years) and adults (19-40 years) with normal hearing using the ChEgSS test. In Experiment 1, data were collected from Spanish/English bilingual and English monolingual adults at multiple, fixed signal-to-noise ratios. Psychometric functions were fitted to the word-level data to characterize variability across target words in each language and in each masker condition. In Experiment 2, Spanish/English bilingual adults were tested using an adaptive tracking procedure to evaluate the influence of different target-word normalization approaches on the reliability of estimates of masked-speech recognition thresholds corresponding to 70.7% correct word recognition and to determine the optimal number of reversals needed to obtain reliable estimates. In Experiment 3, Spanish/English bilingual and English monolingual children completed speech perception testing using the ChEgSS test to (1) characterize feasibility across age and language group, (2) evaluate test-retest reliability, and (3) establish normative data. RESULTS: Experiments 1 and 2 yielded data that are essential for stimulus normalization, optimizing threshold estimation procedures, and interpreting threshold data across test language and masker type. Findings obtained from Spanish/English bilingual and English monolingual children with normal hearing in Experiment 3 support feasibility and demonstrate reliability for use with children as young as 4 years of age. Equivalent results for testing in English and Spanish were observed for Spanish/English bilingual children, contingent on adequate proficiency in the target language. Regression-based threshold norms were established for Spanish/English bilingual and English monolingual children between 4 and 17 years of age. CONCLUSIONS: The present findings indicate the ChEgSS test is appropriate for testing a wide age range of children with normal hearing in either Spanish, English, or both languages. The ChEgSS test is currently being evaluated in a large cohort of patients with hearing loss at pediatric audiology clinics across the United States. Results will be compared with normative data established in the present study and with established clinical measures used to evaluate English- and Spanish-speaking children. Questionnaire data from parents and clinician feedback will be used to further improve test procedures.

The Chinese Zodiac-in-Noise Test: An Internet-Based Speech-in-Noise Test for Large-Scale Hearing Screening.

OBJECTIVES: Motivated by the growing need for hearing screening in China, the present study has two objectives. First, to develop and validate a new test, called the Chinese Zodiac-in-noise (ZIN) test, for large-scale hearing screening in China. Second, to conduct a large-scale remote hearing screening in China, using the ZIN test developed. DESIGN: The ZIN test was developed following a similar procedure as the digits-in-noise test but emphasizes the importance of consonant recognition by employing the 12 zodiac animals in traditional Chinese culture as speech materials. It measures the speech reception threshold (SRT) using triplets of Chinese zodiac animals in speech-shaped noise with an adaptive procedure. RESULTS: Normative data of the test were obtained in a group of 140 normal-hearing listeners, and the performance of the test was validated by comparisons with pure-tone audiometry in 116 listeners with various hearing abilities. The ZIN test has a reference SRT of -11.0 ± 1.6 dB in normal-hearing listeners with a test-retest variability of 1.7 dB and can be completed in 3 minutes. The ZIN SRT is highly correlated with the better-ear pure-tone threshold ( r = 0.82). With a cutoff value of -7.7 dB, the ZIN test has a sensitivity of 0.85 and a specificity of 0.94 for detecting a hearing loss of 25 dB HL or more at the better ear.A large-scale remote hearing screening involving 30,552 participants was performed using the ZIN test. The large-scale study found a hearing loss proportion of 21.0% across the study sample, with a high proportion of 57.1% in the elderly study sample aged over 60 years. Age and gender were also observed to have associations with hearing loss, with older individuals and males being more likely to have hearing loss. CONCLUSIONS: The Chinese ZIN test is a valid and efficient solution for large-scale hearing screening in China. Its remote applications may improve access to hearing screening and enhance public awareness of hearing health.

Age standardization and time-of-day performance for the Oldenburg Sentence Test (OLSA): results from the population-based Gutenberg Health Study.

PURPOSE: The Oldenburg Sentence Test (OLSA) is a German matrix test designed to determine speech recognition thresholds (SRT). It is widely used for hearing-aids and cochlear implant fitting, but an age-adjusted standard is still lacking. In addition, knowing that the ability to concentrate is an important factor in OLSA performance, we hypothesized that OLSA performance would depend on the time of day it was administered. The aim of this study was to propose an age standardization for the OLSA and to determine its diurnal performance. METHODS: The Gutenberg Health Study is an ongoing population-based study and designed as a single-centre observational, prospective cohort study. Participants were interviewed about common otologic symptoms and tested with pure-tone audiometry and OLSA. Two groups-subjects with and without hearing loss-were established. The OLSA was performed in two runs. The SRT was evaluated for each participant. Results were characterized by age in 5-year cohorts, gender and speech recognition threshold (SRT). A time stamp with an hourly interval was also implemented. RESULTS: The mean OLSA SRT was - 6.9 ± 1.0 dB (group 1 male) and - 7.1 ± 0.8 dB (group 1 female) showing an inverse relationship with age in the whole cohort, whereas a linear increase was observed in those without hearing loss. OLSA-SRT values increased more in males than in females with increasing age. No statistical significance was found for the diurnal performance. CONCLUSIONS: A study with 2900 evaluable Oldenburg Sentence Tests is a novelty and representative for the population of Mainz and its surroundings. We postulate an age- and gender-standardized scale for the evaluation of the OLSA. In fact, with an intergroup standard deviation (of about 1.5 dB) compared to the age dependence of 0.7 dB/10 years, this age normalization should be considered as clinically relevant.

Development of an Arabic "Command in Noise" Hearing Test to Assess Fitness for Duty.

Objective: The goal is to implement the developed speech material in a hearing test to assess auditory fitness for duty (AFFD), specifically in areas where the intelligibility of spoken commands is essential. Design: In study 1, a speech corpus with equal intelligibility was constructed using constant stimuli to test each target word's psychometric functions. Study 2 used an adaptive interleaving procedure to maximize equalized terms. Study 3 used Monte Carlo simulations to determine speech test accuracy. Study sample: Study 1 (n = 24) and study 2 (n = 20) were completed by civilians with normal hearing. Study 3 ran 10,000 simulations per condition across various conditions varying in slopes and speech recognition thresholds (SRTs). Results: Studies 1 and 2 produced three 8-word wordlists. The mean, standard deviation in dB SNR is -13.1 1.2 for wordlist 1, -13.7 1.6 for wordlist 2, and -13.7 1.3 for wordlist 3, with word SRTs within 3.4 dB SNR. Study 3 revealed that a 6 dB SNR range is appropriate for equally understandable speech using a closed-set adaptive technique. Conclusion: The developed speech corpus may be used in an AFFD measure. Concerning the homogeneity of the speech in noise test material, care should be taken when generalizing and using ranges and standard deviations from multiple tests.

Psychometrically Equivalent Fante Speech Recognition Threshold Materials by a Female Talker.

PURPOSE: This study aimed to create and evaluate digitally recorded speech materials for speech recognition threshold (SRT) testing among children and adults in Fante. Fifty-one (51) familiar trisyllabic words were chosen from a list of 107 widely used trisyllabic Fante words. They were digitally captured and edited to create the same root mean square as a 1-kHz calibration tone. METHOD: The study used a three-phase cross-sectional study method. Twenty native Fante speakers with normal hearing thresholds were selected at random for listener evaluation. For each of the words, the researchers used logistic regression to measure the slope, intercepts, and psychometric function slope at 50% and from 20% to 80%. In the study, the intensity of each word was modified digitally, so that the threshold at 50% of each word was equal to the mean pure-tone average (PTA) of the participants to increase the homogeneity of the thresholds of the selected words. RESULTS: A final list of 25 familiar homogenous words with the same tone patterns of slopes greater than 7%/dB was finally selected and recorded for speech audiometry in Fante. CONCLUSIONS: Psychometrically equivalent trisyllabic words in Fante were successfully developed and evaluated for SRT testing in Ghana. There is a need for the development of speech audiometry materials in other Ghanaian languages.

The German hearing in noise test with a female talker: development and comparison with German male speech test.

PURPOSE: The aim of the study was to develop the German Hearing in Noise Test (HINT) with female speaker by fulfilling the recommendations by International Collegium of Rehabilitative Audiology (ICRA) for using a female speaker to create new multilingual speech tests and to determine norms and to compare these norms with German male speech tests-the male speakers HINT and the Oldenburg Sentence Test (OLSA). METHODS: The HINT with a female speaker consists of the same speech material as the male speaking HINT. After recording the speech material, 10 normal hearing subjects were included to determine the performance-intensity function (PI function). 24 subjects were part of the measurements to determine the norms and compare them with the norms of male HINT and OLSA. Comparably, adaptive, open-set methods under headphones (HINT) and sound field (OLSA) were used. RESULTS: Acoustic phonetic analysis demonstrated significant difference in mean fundamental frequency, its range and mean speaking rate between both HINT speakers. The calculated norms by three of the tested four conditions of the HINT with a female speaker are not significantly different from the norms with a male speaker. No significant effect of the speaker's gender of the first HINT measurement and no significant correlation between the threshold results of the HINT and the OLSA were determined. CONCLUSIONS: The Norms for German HINT with a female speaker are comparable to the norms of the HINT with a male speaker. The speech intelligibility score of the HINT does not depend on the speakers' gender despite significant difference of acoustic-phonetic parameters between the female and male HINT speaker's voice. Instead, the speech intelligibility rating must be seen as a function of the used speech material.

The one-up one-down adaptive (staircase) procedure in speech-in-noise testing: Standard error of measurement and fluctuations in the track.

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 (SDtrack)]. 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 SDtrack. Hearing loss and non-ideal behavior (inattentiveness, fatigue, and giving up when the task becomes too difficult) slightly increase the average value of SDtrack. SDtrack, however, poorly discriminates between reliable and unreliable SRT estimates.

Validation of Male Talker Recordings of the Spanish Pediatric Speech Recognition Threshold Test and the Spanish Pediatric Picture Identification Test.

PURPOSE: The purpose of this study was to validate recordings of the Spanish Pediatric Speech Recognition Threshold (SPSRT) test and Spanish Pediatric Picture Identification Test (SPPIT) for Spanish-speaking children using a native, bilingual Spanish-English male talker of Castilian peninsular dialect from Spain. METHOD: Seventy native Spanish-speaking children from a variety of countries participated. Fifty-eight participants had normal hearing, and the remaining 12 had mild hearing loss in at least one ear. Male talker recordings of the SPSRT and SPPIT were administered to obtain baseline validation data. Participants listened to the stimuli and pointed to the appropriate item on the picture boards that represented the word they heard. RESULTS: Mean SRTs were within 5 dB of mean pure-tone averages resulting in a positive correlation. Performance-intensity functions for the SPPIT showed minimal significant differences across the three test lists, and performance increased as the sensation level increased. CONCLUSIONS: The male talker recordings of the SPSRT and SPPIT are valid speech perception picture-pointing assessments that can be used with Spanish-speaking children. The recordings present the Spanish target word while simultaneously presenting the English interpretation for ease of scoring.

Development and evaluation of video recordings for the OLSA matrix sentence test.

OBJECTIVE: The aim was to create and validate an audiovisual version of the German matrix sentence test (MST), which uses the existing audio-only speech material. DESIGN: Video recordings were recorded and dubbed with the audio of the existing German MST. The current study evaluates the MST in conditions including audio and visual modalities, speech in quiet and noise, and open and closed-set response formats. SAMPLE: One female talker recorded repetitions of the German MST sentences. Twenty-eight young normal-hearing participants completed the evaluation study. RESULTS: The audiovisual benefit in quiet was 7.0 dB in sound pressure level (SPL). In noise, the audiovisual benefit was 4.9 dB in signal-to-noise ratio (SNR). Speechreading scores ranged from 0% to 84% speech reception in visual-only sentences (mean = 50%). Audiovisual speech reception thresholds (SRTs) had a larger standard deviation than audio-only SRTs. Audiovisual SRTs improved successively with increasing number of lists performed. The final video recordings are openly available. CONCLUSIONS: The video material achieved similar results as the literature in terms of gross speech intelligibility, despite the inherent asynchronies of dubbing. Due to ceiling effects, adaptive procedures targeting 80% intelligibility should be used. At least one or two training lists should be performed.

The digit triplet test as a self-test for hearing screening at the age of school-entry.

OBJECTIVE: The current study aimed to investigate the feasibility of the digit triplet test (DTT) as a self-test in normal-hearing children at school-entry age (5-6 years) compared to an administrator-controlled test. DESIGN AND STUDY SAMPLE: Thirty-seven first grade elementary school children took part in this study. Next to a pure-tone screening, the test battery consisted of a DTT speech-in-noise screening (self-test and administrator-controlled assessment), and cognitive tests related to auditory/working memory and attention skills. RESULTS: The reference-SRT ± 2SD, obtained with the administrator-controlled DTT, was -9.8 ± 1.6 dB SNR, and could be estimated with a precision of 0.7 dB. The test duration for one ear was about 4.5 min. Self-tests resulted in higher (poorer) SRTs. Only a small proportion of children performed stably across repeated self-test administrations. With about 6 min for one ear, the test duration was rather long. The influence of auditory/working memory and attentional abilities appeared to be limited. CONCLUSION: Our data suggest that a self-administered DTT is not suitable for a large proportion of children at school-entry.

Surgical and functional outcomes of two types of transcutaneous bone conduction implants.

OBJECTIVE: This study aimed to evaluate surgical and functional outcomes, in a tertiary referral centre, of two different types of semi-implantable transcutaneous bone conduction devices. METHOD: This study involved prospective data collection and review of patients implanted between November 2014 and December 2016. Glasgow Hearing Aid Inventory (Glasgow Hearing Aid Benefit Profile or Glasgow Hearing Aid Difference Profile) and Client Oriented Scale of Improvement were completed where appropriate. Surgical and audiological outcomes were recorded in the surgical notes. RESULTS: Glasgow Hearing Aid Difference Profile and Glasgow Hearing Aid Benefit Profile showed similar mean score in the active and the passive transcutaneous bone conduction devices. Client Oriented Scale of Improvement showed improvements in listening situations. Post-operative speech reception threshold showed better mean threshold in the active transcutaneous bone conduction devices group when compared with the passive transcutaneous bone conduction devices group. No device failures or surgical complications existed in either group, with the surgical time being less in the passive transcutaneous bone conduction devices group. CONCLUSION: Both devices are reliable semi-implantable transcutaneous bone conduction devices with excellent surgical and functional outcomes and patient satisfaction. Overall surgical time was much less in the passive transcutaneous bone conduction devices group with no necessity for pre-planning. This is much easier to remove with the possibility of conversion to other devices in the manufacturer's portfolio and wide-ranging wireless accessories. Further studies are needed to assess the longer-term results in a bigger population.

Comparing audiometric parameters between crushed and intact cartilage tympanoplasty: a double-blinded, randomised, controlled trial study.

OBJECTIVE: To investigate hearing and the take rate of crushed cartilage grafts in tympanoplasty. METHODS: In this double-blinded, randomised, controlled trial, 46 patients with tympanic membrane perforation were enrolled. A conchal cartilage graft was used for reconstruction in both intervention and control groups. In the intervention group, crushed cartilage was used. The success rate and hearing results were ascertained every four months over a one-year follow-up period. RESULTS: A total of 36 patients - 20 in the intervention group and 16 in the control group - completed one year of follow up. There were no statistically significant differences between the two groups in mean air-bone gap, bone conduction threshold, speech discrimination score or speech reception threshold. CONCLUSION: The reduction in living cells after crushed cartilage tympanoplasty may decrease the rigidity and the volume of the graft, but may not necessarily improve the hearing results.

Tinnitus impairs segregation of competing speech in normal-hearing listeners.

Many tinnitus patients report difficulties understanding speech in noise or competing talkers, despite having "normal" hearing in terms of audiometric thresholds. The interference caused by tinnitus is more likely central in origin. Release from informational masking (more central in origin) produced by competing speech may further illuminate central interference due to tinnitus. In the present study, masked speech understanding was measured in normal hearing listeners with or without tinnitus. Speech recognition thresholds were measured for target speech in the presence of multi-talker babble or competing speech. For competing speech, speech recognition thresholds were measured for different cue conditions (i.e., with and without target-masker sex differences and/or with and without spatial cues). The present data suggest that tinnitus negatively affected masked speech recognition even in individuals with no measurable hearing loss. Tinnitus severity appeared to especially limit listeners' ability to segregate competing speech using talker sex differences. The data suggest that increased informational masking via lexical interference may tax tinnitus patients' central auditory processing resources.

An Automated Speech-in-Noise Test for Remote Testing: Development and Preliminary Evaluation.

Purpose The aim of this study was to develop and evaluate a novel, automated speech-in-noise test viable for widespread in situ and remote screening. Method Vowel-consonant-vowel sounds in a multiple-choice consonant discrimination task were used. Recordings from a professional male native English speaker were used. A novel adaptive staircase procedure was developed, based on the estimated intelligibility of stimuli rather than on theoretical binomial models. Test performance was assessed in a population of 26 young adults (YAs) with normal hearing and in 72 unscreened adults (UAs), including native and nonnative English listeners. Results The proposed test provided accurate estimates of the speech recognition threshold (SRT) compared to a conventional adaptive procedure. Consistent outcomes were observed in YAs in test/retest and in controlled/uncontrolled conditions and in UAs in native and nonnative listeners. The SRT increased with increasing age, hearing loss, and self-reported hearing handicap in UAs. Test duration was similar in YAs and UAs irrespective of age and hearing loss. The test-retest repeatability of SRTs was high (Pearson correlation coefficient = .84), and the pass/fail outcomes of the test were reliable in repeated measures (Cohen's κ = .8). The test was accurate in identifying ears with pure-tone thresholds > 25 dB HL (accuracy = 0.82). Conclusion This study demonstrated the viability of the proposed test in subjects of varying language in terms of accuracy, reliability, and short test time. Further research is needed to validate the test in a larger population across a wider range of languages and hearing loss and to identify optimal classification criteria for screening purposes.

Speech-in-noise detection is related to auditory working memory precision for frequency.

Speech-in-noise (SiN) perception is a critical aspect of natural listening, deficits in which are a major contributor to the hearing handicap in cochlear hearing loss. Studies suggest that SiN perception correlates with cognitive skills, particularly phonological working memory: the ability to hold and manipulate phonemes or words in mind. We consider here the idea that SiN perception is linked to a more general ability to hold sound objects in mind, auditory working memory, irrespective of whether the objects are speech sounds. This process might help combine foreground elements, like speech, over seconds to aid their separation from the background of an auditory scene. We investigated the relationship between auditory working memory precision and SiN thresholds in listeners with normal hearing. We used a novel paradigm that tests auditory working memory for non-speech sounds that vary in frequency and amplitude modulation (AM) rate. The paradigm yields measures of precision in frequency and AM domains, based on the distribution of participants' estimates of the target. Across participants, frequency precision correlated significantly with SiN thresholds. Frequency precision also correlated with the number of years of musical training. Measures of phonological working memory did not correlate with SiN detection ability. Our results demonstrate a specific relationship between working memory for frequency and SiN. We suggest that working memory for frequency facilitates the identification and tracking of foreground objects like speech during natural listening. Working memory performance for frequency also correlated with years of musical instrument experience suggesting that the former is potentially modifiable.

Correlating performance on the Listening in Spatialised Noise - Sentences test (LiSN-S) with the Listening in Spatialised Noise - Universal test (LiSN-U).

Objective: The aim of this study was to correlate 6- to 7-year-old children's results on each condition of the Listening in Spatialised Noise - Sentences test (LiSN-S) with the new language-independent version, the Listening in Spatialised Noise - Universal test (LiSN-U), to examine the strength of the relationship between them and with memory in a small sample of typically developing children.Design: Correlational analysis.Study samples: Sixteen typically developing 6- to 7-year-old children completed the LiSN-S and LiSN-U as well as the Test of Auditory Processing Skills - Third Edition (TAPS-3) number memory forward and reversed subtests which assess short-term memory and working memory, respectively.Results: Moderate positive correlations were found between LiSN-S and LiSN-U spatially separated conditions (though this did not reach significance), and co-located conditions. Correlations between the LiSN-S and LiSN-U conditions and number memory forward and reversed subtests were not significant.Conclusion: This study shows a moderate relationship between the LiSN-S and LiSN-U when the distractors and target speech are co-located. A study with a larger sample of participants is needed to further understand the relationship between the two tests, especially for the spatially separated condition.

Development of the Continuous Number Identification Test (CNIT): feasibility of dynamic assessment of speech intelligibility.

Objective: The present study was motivated by a need for a speech intelligibility test capable of indexing dynamic changes in the environment and adaptive processing in hearing aids. The Continuous Number Identification Test (CNIT) was developed to meet these aims.Design: From one location in the free field, speech was presented in noise (∼2 words/s) with a 100-ms inter-word interval. On average, every fourth word was a target digit and all other words were monosyllabic words. Non-numeric words had a fixed presentation level such that the dominant signal-to-noise-ratio (SNR) was held at +6 dB SNR relative to background maskers. To prevent ceiling effects, however, targets were presented at a user-specific SNR, determined by an initial adaptive-tracking procedure that estimated the 79.4% speech reception threshold.Study sample: Ten normal-hearing listeners participated.Results: The CNIT showed comparable psychometric qualities of other established speech tests for long time scales (Exp. 1). Target-location changes did not affect performance on the CNIT (Exp. 2), but the test did show high temporal resolution in assessing sudden changes to SNR (Exp. 3).Conclusions: The CNIT is highly customisable, and the initial experiments tested feasibility of its primary features which set it apart from currently available speech-in-noise tests.

Voice fundamental frequency differences and speech recognition with noise and speech maskers in cochlear implant recipients.

Cochlear implant (CI) recipients are limited in their perception of voice cues, such as the fundamental frequency (F0). This has important consequences for speech recognition when several talkers speak simultaneously. This examination considered the comparison of clear speech and noise-vocoded sentences as maskers. For the speech maskers it could be shown that good CI performers are able to benefit from F0 differences between target and masker. This was due to the fact that a F0 difference of 80 Hz significantly reduced target-masker confusions, an effect that was slightly more pronounced in bimodal than in bilateral users.