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 influence of the stimulus level used to prescribe nonlinear frequency compression on speech perception.

BACKGROUND: Nonlinear frequency compression (NFC) is a signal processing technique designed to lower high frequency inaudible sounds for a listener to a lower frequency that is audible. Because the maximum frequency that is audible to a listener with hearing loss will vary with the input speech level, the input level used to set nonlinear frequency compression could impact speech recognition. PURPOSE: The purpose of this study was to determine the influence of the input level used to set nonlinear frequency compression on nonsense syllable recognition. RESEARCH DESIGN: Nonsense syllable recognition was measured for three NFC fitting condition (i.e., with nonlinear frequency compression set based on speech input levels of 50-, 60-, and 70-dB SPL, respectively), as well as without nonlinear frequency compression (restricted bandwidth condition). STUDY SAMPLE: Twenty-three adults (ages 42-80 years old) with hearing loss. DATA COLLECTION AND ANALYSIS: Data were collected, monaurally, using a hearing aid simulator. The start frequency and frequency compression ratios were set based on the SoundRecover Fitting Assistant. Speech stimuli were 657 consonant-vowel-consonant nonwords presented at 50, 60, and 70 dB SPL and mixed with steady noise (6 dB SNR) and scored based on entire word, initial consonant, vowel, and final consonant. Linear mixed effects examined the effects of NFC fitting condition , presentation level, and scoring method on percent correct recognition. Additional predictor variables of start frequency and frequency-compression ratio were examined. RESULTS: Nonsense syllable recognition increased as presentation level increased. Nonsense syllable recognition for all presentation levels was highest when nonlinear frequency compression was set based on the 70 dB SPL input level and decreased significantly when set based on the 60- and 50-dB SPL inputs. Relative to consonant recognition, there was a greater reduction in vowel recognition. Nonsense syllable recognition between NFC fitting conditions improved with increases in the start frequency, where higher start frequencies led to better nonsense word recognition. CONCLUSIONS: Nonsense syllable recognition was highest when setting nonlinear frequency compression based on a 70 dB SPL presentation level and suggest that a high presentation level should be used to determine nonlinear frequency compression parameters for an individual patient.

Predictors of Susceptibility to Noise and Speech Masking Among School-Age Children With Hearing Loss or Typical Hearing.

OBJECTIVES: The purpose of this study was to evaluate effects of masker type and hearing group on the relationship between school-age children's speech recognition and age, vocabulary, working memory, and selective attention. This study also explored effects of masker type and hearing group on the time course of maturation of masked speech recognition. DESIGN: Participants included 31 children with normal hearing (CNH) and 41 children with mild to severe bilateral sensorineural hearing loss (CHL), between 6.7 and 13 years of age. Children with hearing aids used their personal hearing aids throughout testing. Audiometric thresholds and standardized measures of vocabulary, working memory, and selective attention were obtained from each child, along with masked sentence recognition thresholds in a steady state, speech-spectrum noise (SSN) and in a two-talker speech masker (TTS). Aided audibility through children's hearing aids was calculated based on the Speech Intelligibility Index (SII) for all children wearing hearing aids. Linear mixed effects models were used to examine the contribution of group, age, vocabulary, working memory, and attention to individual differences in speech recognition thresholds in each masker. Additional models were constructed to examine the role of aided audibility on masked speech recognition in CHL. Finally, to explore the time course of maturation of masked speech perception, linear mixed effects models were used to examine interactions between age, masker type, and hearing group as predictors of masked speech recognition. RESULTS: Children's thresholds were higher in TTS than in SSN. There was no interaction of hearing group and masker type. CHL had higher thresholds than CNH in both maskers. In both hearing groups and masker types, children with better vocabularies had lower thresholds. An interaction of hearing group and attention was observed only in the TTS. Among CNH, attention predicted thresholds in TTS. Among CHL, vocabulary and aided audibility predicted thresholds in TTS. In both maskers, thresholds decreased as a function of age at a similar rate in CNH and CHL. CONCLUSIONS: The factors contributing to individual differences in speech recognition differed as a function of masker type. In TTS, the factors contributing to individual difference in speech recognition further differed as a function of hearing group. Whereas attention predicted variance for CNH in TTS, vocabulary and aided audibility predicted variance in CHL. CHL required a more favorable signal to noise ratio (SNR) to recognize speech in TTS than in SSN (mean = +1 dB in TTS, -3 dB in SSN). We posit that failures in auditory stream segregation limit the extent to which CHL can recognize speech in a speech masker. Larger sample sizes or longitudinal data are needed to characterize the time course of maturation of masked speech perception in CHL.

Impact of room acoustics and visual cues on speech perception and talker localization by children with mild bilateral or unilateral hearing loss.

Introduction: This study evaluated the ability of children (8-12 years) with mild bilateral or unilateral hearing loss (MBHL/UHL) listening unaided, or normal hearing (NH) to locate and understand talkers in varying auditory/visual acoustic environments. Potential differences across hearing status were examined. Methods: Participants heard sentences presented by female talkers from five surrounding locations in varying acoustic environments. A localization-only task included two conditions (auditory only, visually guided auditory) in three acoustic environments (favorable, typical, poor). Participants were asked to locate each talker. A speech perception task included four conditions [auditory-only, visually guided auditory, audiovisual, auditory-only from 0° azimuth (baseline)] in a single acoustic environment. Participants were asked to locate talkers, then repeat what was said. Results: In the localization-only task, participants were better able to locate talkers and looking times were shorter with visual guidance to talker location. Correct looking was poorest and looking times longest in the poor acoustic environment. There were no significant effects of hearing status/age. In the speech perception task, performance was highest in the audiovisual condition and was better in the visually guided and auditory-only conditions than in the baseline condition. Although audiovisual performance was best overall, children with MBHL or UHL performed more poorly than peers with NH. Better-ear pure-tone averages for children with MBHL had a greater effect on keyword understanding than did poorer-ear pure-tone averages for children with UHL. Conclusion: Although children could locate talkers more easily and quickly with visual information, finding locations alone did not improve speech perception. Best speech perception occurred in the audiovisual condition; however, poorer performance by children with MBHL or UHL suggested that being able to see talkers did not overcome reduced auditory access. Children with UHL exhibited better speech perception than children with MBHL, supporting benefits of NH in at least one ear.

Comparing criteria for deviation from hearing aid prescriptive targets in children.

OBJECTIVE: To determine if a stricter criterion for paediatric hearing aid fitting for proximity of fit-to-target of <3 dB root-mean-square (RMS) error produces better audibility and outcomes compared to the current <5 dB criterion, and to examine the relationship between aided audibility and RMS error by degree of hearing loss. DESIGN: We evaluated the influence of unaided hearing level on the relationship between RMS error and aided audibility. We assessed the effect of RMS error category (<3, 3-5, >5 dB) on aided audibility, speech recognition, expressive vocabulary, and morphosyntax. STUDY SAMPLE: The study included 2314 hearing aid verification measurements from 307 children with hearing aids. RESULTS: Children who met a <3 dB criterion had higher aided audibility than children who met no criterion (>5 dB error). Results showed no differences in speech recognition or vocabulary by error category, but children with <3 dB error demonstrated better morphosyntax than children with 3-5 and >5 dB RMS error. CONCLUSIONS: Fittings that are close to prescriptive targets provide a more positive outcome for children with hearing aids. Using probe microphone measures to adjust hearing aids to within 3 dB may benefit language abilities in children.

Story Generation and Narrative Retells in Children Who Are Hard of Hearing and Hearing Children.

PURPOSE: The primary goal for this study was to compare story generation and narrative retell performance in children who are hard of hearing (CHH) and hearing children. A secondary goal was to determine factors that influence narrative performance. Research on this topic is important because narrative language competency is an essential communication function. METHOD: Participants included 86 CHH and 53 seven-year-old hearing children who had completed a test battery composed of vocabulary, grammar, phonological processing, story generation, and narrative retell tasks. Coders who were blind to hearing status used a scoring rubric to judge the quality of narrative macrostructure in story generation and narrative retells. Data were analyzed using analysis of variance to determine group differences and correlational models to examine individual differences. RESULTS: At 7 years of age, CHH demonstrated significant deficits in narrative macrostructure compared to hearing children, with larger delays in narrative retell than story generation. Vocabulary, grammar, and phonological memory acted as mediators in the relationship between hearing status and story generation; grammar acted as a mediator between hearing status and narrative retell. Auditory access variables accounted for a significant proportion of shared variance in story generation skills for CHH. CONCLUSIONS: School-age CHH are at risk for delays in narrative production, particularly with retelling stories. The results of this study highlight a narrative coding approach and task procedures that are sensitive to differences in language levels and may be clinically useful for professionals working with early school-age children.

Predicting wideband real-ear-to-coupler differences in children using wideband acoustic immittance.

Individual differences in ear-canal acoustics introduce variability into hearing aid output that can affect speech audibility. Measuring ear-canal acoustics in young children can be challenging, and relying on normative real-ear-to-coupler difference (RECD) transforms can lead to large fitting errors. Acoustic immittance measures characterize the impedance of the ear and are more easily measured than RECD. Using 226 Hz tympanometry to predict the RECD is more accurate than using age-based average RECD values. The current study sought to determine whether wideband acoustic immittance measurements could improve predictions of wideband real-ear-to-coupler difference (wRECD). 150 children ages 2-10 years with intact tympanic membranes underwent wRECD and wideband acoustic immittance measures in each ear. Three models were constructed to predict each child's measured wRECD: the age-based average wRECD, 226 Hz admittance wRECD, and wideband absorbance wRECD. The average age-based wRECD model predicted the child's measured wRECD within 3 dB in 62% of cases, but both the 226 Hz admittance and wideband absorbance wRECD were within 3 dB in 90% of cases. Using individual 226 Hz or wideband absorbance to predict wRECD improved the accuracy and precision of transforms used for pediatric hearing aid fitting.

Quantifying Access to Speech in Children with Hearing Loss: The Influence of the Work of Pat Stelmachowicz on Measures of Audibility.

This article reviews the research of Pat Stelmachowicz on traditional and novel measures for quantifying speech audibility (i.e., pure-tone average [PTA], the articulation/audibility index [AI], the speech intelligibility index, and auditory dosage) as predictors of speech perception and language outcomes in children. We discuss the limitations of using audiometric PTA as a predictor of perceptual outcomes in children and how Pat's research shed light on the importance of measures that characterize high-frequency audibility. We also discuss the AI, Pat's work on the calculation of the AI as a hearing aid outcome measure, and how this work led to the application of the speech intelligibility index as a clinically utilized measure of unaided and aided audibility. Finally, we describe a novel measure of audibility-auditory dosage-that was developed based on Pat's work on audibility and hearing aid use for children who are hard of hearing.

Predicting children's real-ear-to-coupler differences based on tympanometric data.

OBJECTIVE: Paediatric hearing-aid verification relies on measures of output obtained from the ear canal or in a coupler with the child's real-ear-to-coupler difference (RECD). Measured RECD cannot always be completed in children, leading to fitting inaccuracies. Audiologists often have tympanometry data that characterises the child's ear-canal acoustics. The goal of this study was to determine if tympanometry can be used to improve predictions of measured RECD. DESIGN: A retrospective analysis of RECD and admittance, tympanometric peak pressure, and equivalent ear-canal volume from 226 Hz tympanometry collected as part of a longitudinal study of children with hearing loss were modelled with Bayesian hierarchical regression. STUDY SAMPLE: Two-hundred sixty-six children with mild-to-severe hearing loss contributed data. RESULTS: Age-based average RECD models were within 3 dB of measured RECD values in 54% of cases with normal middle ear status and 50.6% of cases with abnormal middle ear status. Immittance-predicted RECD were within 3 dB in 69.6% of cases with normal middle ear status and 74.4% of cases with abnormal middle ear status. CONCLUSION: Immittance-predicted RECD was more accurate than age-based average RECD, particularly in children with abnormal middle ear status. The findings suggest that 226 Hz tympanometry could be used clinically to improve predictions of measured RECD when it cannot be measured.

Hearing Thresholds, Speech Recognition, and Audibility as Indicators for Modifying Intervention in Children With Hearing Aids.

OBJECTIVES: The purpose of this study was to determine if traditional audiologic measures (e.g., pure-tone average, speech recognition) and audibility-based measures predict risk for spoken language delay in children who are hard of hearing (CHH) who use hearing aids (HAs). Audibility-based measures included the Speech Intelligibility Index (SII), HA use, and auditory dosage, a measure of auditory access that weighs each child's unaided and aided audibility by the average hours of HA use per day. The authors also sought to estimate values of these measures at which CHH would be at greater risk for delayed outcomes compared with a group of children with typical hearing (CTH) matched for age and socioeconomic status, potentially signaling a need to make changes to a child's hearing technology or intervention plan. DESIGN: The authors compared spoken language outcomes of 182 CHH and 78 CTH and evaluated relationships between language and audiologic measures (e.g., aided SII) in CHH using generalized additive models. They used these models to identify values associated with falling below CTH (by > 1.5 SDs from the mean) on language assessments, putting CHH at risk for language delay. RESULTS: Risk for language delay was associated with aided speech recognition in noise performance (<59% phonemes correct, 95% confidence interval [55%, 62%]), aided Speech Intelligibility Index (SII < 0.61, 95% confidence internal [.53,.68]), and auditory dosage (dosage < 6.0, 95% confidence internal [5.3, 6.7]) in CHH. The level of speech recognition in quiet, unaided pure-tone average, and unaided SII that placed children at risk for language delay could not be determined due to imprecise estimates with broad confidence intervals. CONCLUSIONS: Results support using aided SII, aided speech recognition in noise measures, and auditory dosage as tools to facilitate clinical decision-making, such as deciding whether changes to a child's hearing technology are warranted. Values identified in this article can complement other metrics (e.g., unaided hearing thresholds, aided speech recognition testing, language assessment) when considering changes to intervention, such as adding language supports, making HA adjustments, or referring for cochlear implant candidacy evaluation.

Somatosensory gating is related to behavioral and verbal outcomes in children with mild-to-severe hearing loss.

Sensory gating is a process by which the brain filters out redundant information to preserve neural resources for behaviorally relevant stimuli. Although studies have shown alterations in auditory and visual processing in children who are hard-of-hearing (CHH) relative to children with normal hearing (CNH), it is unclear whether these alterations extend to the somatosensory domain, and how aberrations in sensory processing affect sensory gating. In this study, CHH and CNH were presented with a paired-pulse median nerve stimulation during magnetoencephalography. Stimulus-related gamma neural activity was imaged and virtual time series from peak somatosensory responses were extracted. We found significant effects of both stimulus and group, as well as a significant group-by-stimulus interaction. CHH showed a larger response to stimulation overall, as well as greater differences in gamma power from the first to the second stimulus. However, when looking at the ratio rather than the absolute difference in power, CHH showed comparable gating to CNH. In addition, smaller gating ratios were correlated with better classroom behavior and verbal ability in CHH, but not CNH. Taken together, these data underscore the importance of considering how CHH experience their multisensory environment when interpreting outcomes and designing interventions.

Descriptions of Hearing Loss Severity Differentially Influence Parental Concern about the Impact of Childhood Hearing Loss.

PURPOSE: The purpose of this study was to measure how parent concern about childhood hearing loss varies under different description conditions: classification-based, audibility-based, and simulation-based descriptions. METHOD: We randomly allocated study participants (n = 143) to complete an online survey about expected child difficulties with listening situations with hearing loss. Our participants were parents of children with typical hearing in the 0- to 12-month age range. Participants were exposed to one type of description (classification-based, audibility-based, or simulation-based) and one level of hearing loss (slight, mild, and moderate or their audibility and simulation equivalents), producing nine total groups. Participants rated the level of expected difficulty their child would experience performing age-appropriate listening tasks with the given hearing loss. They also selected what they perceived as the most appropriate intervention from a list of increasingly intense options. RESULTS: Our findings revealed that audibility-based descriptions elicited significantly higher levels of parent concerns about hearing loss than classification-based strategies, but that simulation-based descriptions elicited the highest levels of concern. Those assigned to simulation-based and audibility-based groups also judged relatively more intense intervention options as appropriate compared to those assigned to classification-based groups. CONCLUSIONS: This study expands our knowledge base about descriptive factors that impact levels of parent concern about hearing loss after diagnosis. This has potentially cascading effects on later intervention actions such as fitting hearing technology. It also provides a foundation for developing and testing clinical applications of audibility-based counseling strategies.

Speech-in-speech recognition in preschoolers.

OBJECTIVE: The purpose of this study was to 1) characterise word recognition in a speech masker for preschoolers tested using closed-set, forced-choice procedures and 2) better understand the stimulus and listener factors affecting performance. DESIGN: Speech recognition thresholds (SRTs) in a two-talker masker were evaluated using a picture-pointing response with two sets of disyllabic target words. ChEgSS words were previously developed for children ≥5 years of age, and simple words were developed for preschoolers. Familiarisation ensured accurate identification of target words before testing. STUDY SAMPLE: Participants were 3- and 4-year olds (n = 21) and young adults (n = 10) with normal hearing. RESULTS: Preschoolers and adults had significantly lower SRTs for the simple words than the ChEgSS words, and lower SRTs for early-acquired than later-acquired ChEgSS words. For both word sets, SRTs were approximately 11-dB higher for preschoolers than adults, and child age was associated with SRTs. Preschoolers' receptive vocabulary size predicted performance for ChEgSS words but not simple words. CONCLUSIONS: Preschoolers were more susceptible to speech-in-speech masking than adults, with a similar child-adult difference for the ChEgSS and simple words. Effects of receptive vocabulary in preschoolers' recognition of ChEgSS words indicate that vocabulary size is an important consideration, even when using closed-set methods.

Validation of a tablet-based assessment of auditory sensitivity for researchers.

Quantifying hearing acuity is increasingly important across a wide range of research areas in the behavioral and neurosciences. Scientists have relied on either self-reported hearing status or the availability of diagnostic hearing assessment in past studies. There remains a need for a valid and reliable assessment of auditory sensitivity that can provide estimates of the magnitude of hearing loss, if present, without requirements for professional audiologists, facilities, and equipment that are needed to conduct a diagnostic hearing assessment. The goal of this experiment was to validate the NIH Toolbox® Hearing Threshold Test (HTT), a tablet-based hearing assessment available via iPad application that uses consumer-grade headphones, on a clinical sample of children and adults with varying degrees of hearing acuity. Electroacoustic analysis of the hearing assessment application and headphones demonstrated acoustic outputs within established conformity standards for hearing assessment. Twenty-seven children and 63 adults participated in a standard diagnostic hearing assessment and the experimental tablet-based assessment. The results showed that thresholds from the tablet-based assessment were highly correlated with thresholds from the clinical hearing assessment (r = .83-.93) for children and adults for all frequencies and across a range of levels of hearing acuity. The HTT also met clinical test-retest reliability standards (Cronbach's α > .86). The tablet-based hearing assessment provides acceptable estimates of hearing levels for children and adults when diagnostic audiometric assessment capabilities are not available.

Remote-Microphone Benefit in Noise and Reverberation for Children Who are Hard of Hearing.

BACKGROUND: Remote-microphone (RM) systems are designed to reduce the impact of poor acoustics on speech understanding. However, there is limited research examining the effects of adding reverberation to noise on speech understanding when using hearing aids (HAs) and RM systems. Given the significant challenges posed by environments with poor acoustics for children who are hard of hearing, we evaluated the ability of a novel RM system to address the effects of noise and reverberation. PURPOSE: We assessed the effect of a recently developed RM system on aided speech perception of children who were hard of hearing in noise and reverberation and how their performance compared to peers with "normal" hearing. The effect of aided speech audibility on sentence recognition when using an RM system also was assessed. STUDY SAMPLE: Twenty-two children with mild to severe hearing loss and 17 children with normal "hearing" (7-18 years) participated. DATA COLLECTION AND ANALYSIS: An adaptive procedure was used to determine the signal-to-noise ratio for 50 and 95% correct sentence recognition in noise and noise plus reverberation (RT 300 ms). Linear mixed models were used to examine the effect of listening conditions on speech recognition with RMs for children who were hard of hearing compared to children with "normal" hearing and the effects of aided audibility on performance across all listening conditions for children who were hard of hearing. RESULTS: Children who were hard of hearing had poorer speech recognition for HAs alone than for HAs plus RM. Regardless of hearing status, children had poorer speech recognition in noise plus reverberation than in noise alone. Children who were hard of hearing had poorer speech recognition than peers with "normal" hearing when using HAs alone but comparable or better speech recognition with HAs plus RM. Children with better-aided audibility with the HAs showed better speech recognition with the HAs alone and with HAs plus RM. CONCLUSIONS: Providing HAs that maximize speech audibility and coupling them with RM systems has the potential to improve communication access and outcomes for children who are hard of hearing in environments with noise and reverberation.

Auditory Experience, Speech Sound Production Growth, and Early Literacy in Children Who Are Hard of Hearing.

PURPOSE: Children who are hard of hearing (CHH) are at risk for literacy difficulties. Speech sound production is related to literacy skills in typically hearing children. Speech sound production abilities can also be markedly weak in CHH due to inconsistent access to the speech signal. We longitudinally examined relations between auditory experience, speech sound production abilities, and literacy (i.e., nonword reading and spelling in second grade) in CHH. METHOD: Participants included 166 CHH. All participants used hearing aids (HAs). Auditory experience is a weighted measure of the number of hours of daily HA use and the amount of audibility with and without their HAs. Children's speech sound production was tested 2-3 times between the ages of 3 and 9 years. At age 5 years and again in second grade, children were tested on a battery of language and literacy measures. RESULTS: Auditory experience was significantly correlated with speech sound production abilities, but age at HA fitting was not. Speech sound production abilities at age 5 years did not predict nonword reading in second grade but did predict spelling skills in second grade. CONCLUSIONS: Our results support the importance of auditory experience and speech sound production for later literacy abilities. Specifically, we found that speech sound production abilities and print knowledge at age 5 years are related to second grade spelling outcomes. Interestingly, we found that morphological knowledge at age 5 years was more predictive of decoding in second grade than was speech sound production. Although there are multiple factors that contribute to literacy success, our results underscore the unique contributions of speech sound production abilities in CHH.

Auditory experience modulates fronto-parietal theta activity serving fluid intelligence.

Children who are hard of hearing are at risk for developmental language and academic delays compared with children with normal hearing. Some work suggests that high-order cognitive function, including fluid intelligence, may relate to language and academic outcomes in children with hearing loss, but findings in these studies have been mixed and to date, there have been no studies of the whole-brain neural dynamics serving fluid intelligence in the context of hearing loss. To this end, this study sought to identify the impact of hearing loss and subsequent hearing aid use on the neural dynamics serving abstract reasoning in children who are hard of hearing relative to children with normal hearing using magnetoencephalography. We found significant elevations in occipital and parietal theta activity during early stimulus evaluation in children who are hard of hearing relative to normal-hearing peers. In addition, we found that greater hearing aid use was significantly related to reduced activity throughout the fronto-parietal network. Notably, there were no differences in alpha dynamics between groups during later-stage processing nor did alpha activity correlate with hearing aid use. These cross-sectional data suggest that differences in auditory experience lead to widespread alterations in the neural dynamics serving initial stimulus processing in fluid intelligence in children.

Effects of word familiarity and receptive vocabulary size on speech-in-noise recognition among young adults with normal hearing.

Having a large receptive vocabulary benefits speech-in-noise recognition for young children, though this is not always the case for older children or adults. These observations could indicate that effects of receptive vocabulary size on speech-in-noise recognition differ depending on familiarity of the target words, with effects observed only for more recently acquired and less frequent words. Two experiments were conducted to evaluate effects of vocabulary size on open-set speech-in-noise recognition for adults with normal hearing. Targets were words acquired at 4, 9, 12 and 15 years of age, and they were presented at signal-to-noise ratios (SNRs) of -5 and -7 dB. Percent correct scores tended to fall with increasing age of acquisition (AoA), with the caveat that performance at -7 dB SNR was better for words acquired at 9 years of age than earlier- or later-acquired words. Similar results were obtained whether the AoA of the target words was blocked or mixed across trials. Differences in word duration appear to account for nonmonotonic effects of AoA. For all conditions, a positive correlation was observed between recognition and vocabulary size irrespective of target word AoA, indicating that effects of vocabulary size are not limited to recently acquired words. This dataset does not support differential assessment of AoA, lexical frequency, and other stimulus features known to affect lexical access.

Influence of Audibility and Distortion on Recognition of Reverberant Speech for Children and Adults with Hearing Aid Amplification.

BACKGROUND: Adults and children with sensorineural hearing loss (SNHL) have trouble understanding speech in rooms with reverberation when using hearing aid amplification. While the use of amplitude compression signal processing in hearing aids may contribute to this difficulty, there is conflicting evidence on the effects of amplitude compression settings on speech recognition. Less clear is the effect of a fast release time for adults and children with SNHL when using compression ratios derived from a prescriptive procedure. PURPOSE: The aim of the study is to determine whether release time impacts speech recognition in reverberation for children and adults with SNHL and to determine if these effects of release time and reverberation can be predicted using indices of audibility or temporal and spectral distortion. RESEARCH DESIGN: This is a quasi-experimental cohort study. Participants used a hearing aid simulator set to the Desired Sensation Level algorithm m[i/o] for three different amplitude compression release times. Reverberation was simulated using three different reverberation times. PARTICIPANTS: Participants were 20 children and 16 adults with SNHL. DATA COLLECTION AND ANALYSES: Participants were seated in a sound-attenuating booth and then nonsense syllable recognition was measured. Predictions of speech recognition were made using indices of audibility, temporal distortion, and spectral distortion and the effects of release time and reverberation were analyzed using linear mixed models. RESULTS: While nonsense syllable recognition decreased in reverberation release time did not significantly affect nonsense syllable recognition. Participants with lower audibility were more susceptible to the negative effect of reverberation on nonsense syllable recognition. CONCLUSION: We have extended previous work on the effects of reverberation on aided speech recognition to children with SNHL. Variations in release time did not impact the understanding of speech. An index of audibility best predicted nonsense syllable recognition in reverberation and, clinically, these results suggest that patients with less audibility are more susceptible to nonsense syllable recognition in reverberation.

Variation in Auditory Experience Affects Language and Executive Function Skills in Children Who Are Hard of Hearing.

OBJECTIVE: Children who are hard of hearing (CHH) experience delays in spoken language and executive function, but the mechanisms for these deficits remain unresolved. Differences in auditory experience and language skills have been examined as contributing factors to deficits in executive function, primarily with children who are deaf and children with cochlear implants. The theoretical model of cumulative auditory experience quantifies auditory dosage as how much speech is audible and how often children wear their hearing aids. CHH with higher auditory dosage have better language outcomes than peers with less auditory dosage. However, the effects of auditory experience on executive function have not been studied in CHH. The goal of this study was to examine the influences of auditory experience and language skills on the development of executive function in CHH. DESIGN: We collected measures of aided speech audibility, hearing aid use, executive function, and receptive vocabulary in 177 CHH and 86 children with typical hearing who were 5- to 10 years old and matched for socioeconomic status and nonverbal intelligence. Auditory dosage was calculated by combining each child's average hours of hearing aid use with their audibility for speech to create a variable that quantifies individual differences in auditory access. RESULTS: CHH had lower receptive vocabulary and deficits in executive function related to working memory and selective attention compared to peers with typical hearing. CHH with greater auditory dosage had higher receptive vocabulary than CHH with lower auditory dosage. Better receptive vocabulary was associated with better scores on executive function measures related to working memory and attention. Auditory dosage was also directly associated with measures of verbal working memory. CONCLUSIONS: CHH have deficits in language and some, but not all, areas of executive function related to working memory and attention. Auditory dosage was associated with language abilities and verbal working memory. Language was associated with individual differences in executive function skills related to attention and working memory. These results provide support for systems theories regarding the development of executive function in CHH. Interventions that improve auditory access and language may be effective for improving executive function related to working memory and attention in CHH.