Genome-wide association meta-analysis identifies 48 risk variants and highlights the role of the stria vascularis in hearing loss.

Hearing loss is one of the top contributors to years lived with disability and is a risk factor for dementia. Molecular evidence on the cellular origins of hearing loss in humans is growing. Here, we performed a genome-wide association meta-analysis of clinically diagnosed and self-reported hearing impairment on 723,266 individuals and identified 48 significant loci, 10 of which are novel. A large proportion of associations comprised missense variants, half of which lie within known familial hearing loss loci. We used single-cell RNA-sequencing data from mouse cochlea and brain and mapped common-variant genomic results to spindle, root, and basal cells from the stria vascularis, a structure in the cochlea necessary for normal hearing. Our findings indicate the importance of the stria vascularis in the mechanism of hearing impairment, providing future paths for developing targets for therapeutic intervention in hearing loss.

Perceptual, procedural, and task learning for an auditory temporal discrimination task.

Perceptual learning reflects experience-driven improvements in the ability to detect changes in stimulus characteristics. The time course for perceptual learning overlaps with that for procedural learning (acquiring general skills and strategies) and task learning (learning the perceptual judgment specific to the task), making it difficult to isolate their individual effects. This study was conducted to examine the role of exposure to stimulus, procedure, and task information on learning for auditory temporal-interval discrimination. Eighty-three listeners completed five online sessions that required temporal-interval discrimination (target task). Before the initial session, listeners were differentially exposed to information about the target task's stimulus, procedure, or task characteristics. Learning occurred across sessions, but an exposure effect was not observed. Given the significant learning across sessions and variability within and across listeners, contributions from stimulus, procedure, and task exposure to overall learning cannot be discounted. These findings clarify the influence of experience on temporal perceptual learning and could inform designs of training paradigms that optimize perceptual improvements.

AudioChip: A Deep Phenotyping Approach for Deconstructing and Quantifying Audiological Phenotypes of Self-Reported Speech Perception Difficulties.

OBJECTIVES: About 15% of U.S. adults report speech perception difficulties despite showing normal audiograms. Recent research suggests that genetic factors might influence the phenotypic spectrum of speech perception difficulties. The primary objective of the present study was to describe a conceptual framework of a deep phenotyping method, referred to as AudioChipping, for deconstructing and quantifying complex audiometric phenotypes. DESIGN: In a sample of 70 females 18 to 35 years of age with normal audiograms (from 250 to 8000 Hz), the study measured behavioral hearing thresholds (250 to 16,000 Hz), distortion product otoacoustic emissions (1000 to 16,000 Hz), click-evoked auditory brainstem responses (ABR), complex ABR (cABR), QuickSIN, dichotic digit test score, loudness discomfort level, and noise exposure background. The speech perception difficulties were evaluated using the Speech, Spatial, and Quality of Hearing Scale-12-item version (SSQ). A multiple linear regression model was used to determine the relationship between SSQ scores and audiometric measures. Participants were categorized into three groups (i.e., high, mid, and low) using the SSQ scores before performing the clustering analysis. Audiometric measures were normalized and standardized before performing unsupervised k-means clustering to generate AudioChip. RESULTS: The results showed that SSQ and noise exposure background exhibited a significant negative correlation. ABR wave I amplitude, cABR offset latency, cABR response morphology, and loudness discomfort level were significant predictors for SSQ scores. These predictors explained about 18% of the variance in the SSQ score. The k-means clustering was used to split the participants into three major groups; one of these clusters revealed 53% of participants with low SSQ. CONCLUSIONS: Our study highlighted the relationship between SSQ and auditory coding precision in the auditory brainstem in normal-hearing young females. AudioChip was useful in delineating and quantifying internal homogeneity and heterogeneity in audiometric measures among individuals with a range of SSQ scores. AudioChip could help identify the genotype-phenotype relationship, document longitudinal changes in auditory phenotypes, and pair individuals in case-control groups for the genetic association analysis.

The association of hearing problems with social network strength and depressive symptoms: the cardiovascular health study.

BACKGROUND: research on the association between hearing impairment and psychosocial outcomes is not only limited but also yielded mixed results. METHODS: we investigated associations between annual self-reports of hearing problems, depressive symptoms and social network strength among 5,888 adults from the Cardiovascular Health Study over a period of 9 years. Social network strength and depressive symptoms were defined using the Lubben Social Network Scale (LSNS), and the Center for Epidemiological Studies Depression Scale (CES-D). RESULTS: hearing problems were associated with weaker social networks and more depressive symptoms. These association differed for prevalent versus incident hearing problems. Participants with prevalent hearing problems scored an adjusted 0.47 points lower (95% CI: -2.20, -0.71) on the LSNS and 0.71 points higher (95% CI: 0.23, 1.19) on the CES-D than those without hearing problems. Participants with incident hearing problems had a greater decline of 0.12 points (95% CI: -0.12, -0.03) per year in social network score than individuals with no hearing problems after adjusting for confounders. Females appeared to be more vulnerable to changes in social network strength than males (P-value for interaction = 0.02), but not for changes in depressive score. Accounting for social network score did not appear to attenuate the association between hearing problems and depressive score. CONCLUSION: findings suggest that older adults with prevalent hearing problems may be more at risk for depression, but individuals with incident hearing problems may be at greater risk for a winnowing of their social network.

Unexpected intensity changes in the ear canal during a F(0)-shifted feedback experiment.

Effects of frequency-shifted feedback are typically examined using Eventide Harmonizer Series processors to shift the fundamental frequency (F0) of auditory feedback during vocalizations, eliciting compensatory shifts in speaker F0. Recently, unexpected intensity changes were observed in speakers' ear canals, corresponding with F0 shifts. An investigation revealed that feedback time delays introduced by the processor resulted in phase shifts between feedback and unprocessed voice signals radiating into the ear canal via bone conduction, producing combination waves with gains as high as 6 dB. Shifts of this magnitude potentially alter the interpretation of previously published results and should be controlled in future studies.

Threshold Estimation and Speech Perception Under Hearing Loss Simulation: Examination of the Immersive Hearing Loss and Prosthesis Simulator.

PURPOSE: Hearing loss simulation (HLS) has been recommended for clinical teaching and counseling of patients and their families, so that they can experience hearing impairment. However, few validated procedures for simulating hearing loss are available to instructors and practicing clinicians. The aim of this study was to assess the accuracy of the Immersive Hearing Loss and Prosthesis Simulator (I-HeLPS) on reducing hearing sensitivity and word recognition to determine its adequacy for educational and clinical use. METHOD: Thirty-seven young adults with normal hearing completed hearing threshold and word recognition testing under normal and simulated hearing losses. The accuracy of the nominal hearing threshold settings within the I-HeLPS software was assessed with behavioral detection of frequency-modulated pure tones presented in a calibrated sound field, while listeners wore I-HeLPS headphones. The impact of the HLSs on speech perception was measured using the California Consonant Test. Hearing thresholds, word identification accuracy, and sound confusions were compared across listening conditions. RESULTS: Hearing thresholds increased systematically with worse simulated hearing loss. Performance on the California Consonant Test worsened, and the number of phoneme confusions increased with simulated hearing loss severity. Most of the confusions were place confusions with near neighbors and manner confusions increased as a function of increasing severity of simulated hearing loss. CONCLUSIONS: The I-HeLPS accurately elevated hearing thresholds with increasing HLS severity and impacted word recognition in a manner consistent with sensorineural hearing loss. The simulations were considered reasonable for educational and clinical purposes. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.24520966.

Real-Ear-to-Coupler Difference: Physical and Perceptual Differences.

PURPOSE: The real-ear-to-coupler difference (RECD) is a recommended measure for accurate hearing aid fittings, especially for pediatric populations. However, for adults, many clinicians question whether it is necessary. METHOD: Hearing aids were fit on two groups of 85 older adults seen at a Veterans Administration audiology clinic. One group was fit using RECD measurements, whereas the second group was fit with population-based average RECD values. The two groups had similar pure-tone hearing thresholds. RESULTS: Like previous studies, there was little difference between the measured RECD for the right and left ears among the participants. Although the majority of the measured RECDs were within 1 SD of the mean, approximately 20% of those measured were outside of the normal range. It also was found that all participants produced lower (improved) Hearing Handicap Inventory for Elderly-Screening (HHIE-S) scores from pre- to postfitting, thus suggesting a reduction in self-perceived hearing handicap. CONCLUSIONS: Despite having similar prefitting HHIE-S scores, those participants who had their hearing aids fit using measured RECD values had lower postfitting scores than the group that was fit with average RECD values. Furthermore, there was a significant difference between the groups on several questions of the International Outcome Inventory-Hearing Aids, suggesting that there was higher satisfaction with the fittings based on the custom RECD rather than the fittings based on the average RECD. This study demonstrated that, in addition to performing verification using real-ear measurements, accurate conversion of dB HL to dB SPL using personalized RECD likely improved hearing aid satisfaction.

Need for cognition is associated with the interaction of reward and task-load on effort: A verification and extension study.

Here, we work to provide nuance around the assumption that people will work for rewards. We examine whether individuals' inherent tendency to mobilize cognitive effort (need for cognition, NFC) moderates this effect. We re-analyzed our existing data to verify an effect reported by Sandra and Otto (2018) regarding the association between NFC and reward-induced cognitive effort expenditure, using a more ecological cognitive task design and adding a psychophysiological measure of effort. Specifically, distinct from their short time course visual task-switching paradigm, we used a relatively long course auditory comprehension task paradigm. We found that, consistent with the original study, increased cognitive effort in response to incentive reward depends on individual differences in cognitive motivation (need for cognition). We also found that, to observe consistent phenomena, different indices of effort (behavioral and psychophysiological) need to be considered when evaluating the relationship between the effort expenditure and cognitive motivation. Pupil dilation showed an advantage over reaction time in revealing mental effort mobilized over a prolonged cognitive task. Our results suggest that assessing cognitive motivation when planning a behavior-change program involving reward feedback for positive performance could help to optimize individuals' effort investment.

Getting to YES: The Evolution of the University of Pittsburgh Medical Center Hillman Cancer Center Youth Enjoy Science (YES) Academy.

The University of Pittsburgh Medical Center Hillman Cancer Center Academy (Hillman Academy) has the primary goal of reaching high school students from underrepresented and disadvantaged backgrounds and guiding them through a cutting-edge research and professional development experience that positions them for success in STEM. With this focus, the Hillman Academy has provided nearly 300 authentic mentored research internship opportunities to 239 students from diverse backgrounds over the past 13 years most of whom matriculated into STEM majors in higher education. These efforts have helped shape a more diverse generation of future scientists and clinicians, who will enrich these fields with their unique perspectives and lived experiences. In this paper, we describe our program and the strategies that led to its growth into a National Institutes of Health Youth Enjoy Science-funded program including our unique multi-site structure, tiered mentoring platform, multifaceted recruitment approach, professional and academic development activities, and a special highlight of a set of projects with Deaf and Hard of Hearing students. We also share student survey data from the past six years that indicate satisfaction with the program, self-perceived gains in key areas of scientific development, awareness of careers in STEM, and an increased desire to pursue advanced degrees in STEM.

Hearing loss and risk of depressive symptoms in older adults in the Health ABC study.

Objective: Hearing loss (HL) is highly prevalent among older adults and may lead to increased risk of depressive symptoms. In both cross-sectional and longitudinal analysis, we quantified the association between HL and depressive symptoms, incorporating the variable nature of depressive symptoms and characterizing by race and gender. Methods: Data were from the Health, Aging, and Body Composition study. Depressive symptoms were measured using the Center for Epidemiologic Study Depression Scale short form (CES-D 10), defined as CES-D 10 score ≥10 or treatment for depression. Hearing was defined via four-frequency pure-tone average (PTA) decibel hearing level (dB HL), categorized as normal hearing (PTA ≤25 dB HL), mild HL (PTA26-40 dB HL), and ≥moderate HL (PTA > 40 dB HL). Associations at baseline were quantified using logistic regression, incident depressive symptoms using Cox proportional hazard models, and change in depressive symptoms over time using growth mixture models and multinomial logistic regression. Results: Among 2,089 older adults (1,082 women, 793 Black; mean age 74.0 SD: 2.8), moderate or greater HL was associated with greater odds of concurrent [Odds Ratio (OR):2.45, 95% CI:1.33, 4.51] and incident depressive symptoms [Hazard Ratio (HR):1.26, 95% CI:1.00, 1.58]. Three depressive symptom trajectory patterns were identified from growth mixture models: low, moderate increasing, and borderline high depressive symptom levels. Those with moderate or greater HL were more likely to be in the borderline high depressive-symptom trajectory class than the low trajectory class [Relative Risk Ratio (RRR):1.16, 95% CI:1.01, 1.32]. Conclusions: HL was associated with greater depressive symptoms. Although findings were not statistically significantly different by gender and race, estimates were generally stronger for women and Black participants. Investigation of psychosocial factors and amelioration by hearing aid use could have significant benefit for older adults' quality of life.

Investigation of Embodied Language Processing on Command-Swallow Performance in Healthy Participants.

Purpose During videofluoroscopic examination of swallowing, patients commonly are instructed to hold a bolus in their mouth until they hear a verbal instruction to swallow, which usually consists of the word swallow and is commonly referred to as the command swallow condition. The language-induced motor facilitation theory suggests that linguistic processes associated with the verbal command to swallow should facilitate the voluntary component of swallowing. As such, the purpose of the study was to examine the linguistic influences of the verbal command on swallowing. Method Twenty healthy young adult participants held a 5-ml liquid bolus in their mouth and swallowed the bolus after hearing one of five acoustic stimuli presented randomly: congruent action word (swallow), incongruent action word (cough), congruent pseudoword (spallow), incongruent pseudoword (pough), and nonverbal stimulus (1000-Hz pure tone). Suprahyoid muscle activity during swallowing was measured via surface electromyography (sEMG). Results The onset and peak sEMG latencies following the congruent action word swallow were shorter than latencies following the pure tone and pseudowords but were not different from the incongruent action word. The lack of difference between swallow and cough did not negate the positive impact of real words on timing. In contrast to expectations, sEMG activity duration and rise time were longer following the word swallow than the pure tone and pseudowords but were not different from cough. No differences were observed for peak suprahyoid muscle activity amplitude and fall times. Conclusions Language facilitation was observed in swallowing. The clinical utility of the information obtained in the study may depend on the purposes for using the command swallow and the type of patient being assessed. However, linguistic processing under the command swallow condition may alter swallow behaviors and suggests that linguistic inducement could be useful as a compensatory technique for patients with difficulty initiating oropharyngeal swallows.

Impact of spectrally asynchronous delays on consonant voicing perception.

BACKGROUND: A possible voicing cue used to differentiate voiced and voiceless cognate pairs is envelope onset asynchrony (EOA). EOA is the time between the onsets of two frequency bands of energy (in this study one band was high-pass filtered at 3000 Hz, the other low-pass filtered at 350 Hz). This study assessed the perceptual impact of manipulating EOA on voicing perception of initial stop consonants, and whether normal-hearing and hearing-impaired listeners were sensitive to changes in EOA as a cue for voicing. PURPOSE: The purpose of this study was to examine the effect of spectrally asynchronous auditory delay on the perception of voicing associated with initial stop consonants by normal-hearing and hearing-impaired listeners. RESEARCH DESIGN: Prospective experimental study comparing the perceptual differences of manipulating the EOA cues for two groups of listeners. STUDY SAMPLE: Thirty adults between the ages of 21 and 60 yr completed the study: 17 listeners with normal hearing and 13 listeners with mild-moderate sensorineural hearing loss. DATA COLLECTION AND ANALYSIS: The participants listened to voiced and voiceless stop consonants within a consonant-vowel syllable structure. The EOA of each syllable was varied along a continuum, and identification and discrimination tasks were used to determine if the EOA manipulation resulted in categorical shifts in voicing perception. In the identification task the participants identified the consonants as belonging to one of two categories (voiced or voiceless cognate). They also completed a same-different discrimination task with the same set of stimuli. Categorical perception was confirmed with a d-prime sensitivity measure by examining how accurately the results from the identification task predicted the discrimination results. The influence of EOA manipulations on the perception of voicing was determined from shifts in the identification functions and discrimination peaks along the EOA continuum. The two participant groups were compared in order to determine the impact of EOA on voicing perception as a function of syllable and hearing status. RESULTS: Both groups of listeners demonstrated a categorical shift in voicing perception with manipulation of EOA for some of the syllables used in this study. That is, as the temporal onset asynchrony between low- and high-frequency bands of speech was manipulated, the listeners' perception of consonant voicing changed between voiced and voiceless categories. No significant differences were found between listeners with normal hearing and listeners with hearing loss as a result of the EOA manipulation. CONCLUSIONS: The results of this study suggested that both normal-hearing and hearing-impaired listeners likely use spectrally asynchronous delays found in natural speech as a cue for voicing distinctions. While delays in modern hearing aids are less than those used in this study, possible implications are that additional asynchronous delays from digital signal processing or open-fitting amplification schemes might cause listeners with hearing loss to misperceive voicing cues.

Associations of Hearing Loss and Depressive Symptoms With Incident Disability in Older Adults: Health, Aging, and Body Composition Study.

BACKGROUND: Depressive symptoms and hearing loss (HL) are independently associated with increased risk of incident disability; whether the increased risk is additive is unclear. METHODS: Cox Proportional Hazards models were used to assess joint associations of HL (normal, mild, moderate/severe) and late-life depressive symptoms (defined by a score of ≥8 on the 10-item Center for Epidemiologic Studies-Depression scale) with onset of mobility disability (a lot of difficulty or inability to walk » mile and/or climb 10 steps) and any disability in activities of daily living (ADL), among 2,196 participants of the Health, Aging and Body Composition Study, a cohort of well-functioning older adults aged 70-79 years. Models were adjusted for age, race, sex, education, diabetes, hypertension, and body mass index. RESULTS: Relative to participants with normal hearing and without depressive symptoms, participants without depressive symptoms who had mild or moderate/severe HL had increased risk of incident mobility and ADL disability (hazard ratio [HR] for mobility disability, mild HL:1.34, 95% confidence interval [CI]: 1.09, 1.64 and HR for mobility disability, moderate/severe HL: 1.37, 95% CI: 1.08, 1.75 and HR for ADL disability, mild HL: 1.32, 95% CI: 1.08, 1.63, and HR for ADL disability, moderate/severe HL: 1.42, 95% CI: 1.11, 1.82). Among participants with depressive symptoms, mild HL (HR: 1.71, 95% CI: 1.09, 2.70) was associated with increased risk of incident mobility disability. CONCLUSIONS: Independent of depressive symptoms, risk of incident disability was greater in older adults with HL, regardless of severity. Further research into HL interventions may delay disability onset.

Prevalence of hearing loss in Black and White elders: results of the Cardiovascular Health Study.

PURPOSE: The goal of this study was to determine the impact of age, gender, and race on the prevalence and severity of hearing loss in elder adults, aged 72-96 years, after accounting for income, education, smoking, and clinical and subclinical cardiovascular disease. Methods Air-conduction thresholds for standard and extended high-frequency pure-tones were obtained from a cohort of 548 (out of 717) elderly adults (ages 72-96 years) who were recruited during the Year 11 clinical visit (1999-2000) of the Cardiovascular Health Study (CHS) at the Pittsburgh, Pennsylvania site. Participant smoking, income, education, and cardiovascular disease histories were obtained from the CHS database and were included as factors. RESULTS: Hearing loss was more common and more severe for the participants in their 80s than for those in their 70s-the men more than the women and the White participants more than the Black participants. The inclusion of education, income, smoking, and cardiovascular disease (clinical and subclinical) histories as factors did not substantively impact the overall results. CONCLUSION: Although the data reported in this article were cross-sectional and a cohort phenomenon might have been operational, they suggested that hearing loss is more substantive in the 8th than the 7th decade of life and that race and gender influence this decline in audition. Given the high prevalence in the aging population and the differences across groups, there is a clear need to understand the nature and causes of hearing loss across various groups in order to improve prevention and develop appropriate interventions.

The role of reward and task demand in value-based strategic allocation of auditory comprehension effort.

OBJECTIVES: Listeners who fail to optimize their allocation of effort during auditory comprehension tasks can experience from compromised performance, fatigue and stress, which might result in reduced engagement in social communication activities. Strategically allocating effort based on costs and perceived benefits are commonly observed in the research of effortful physical and visual behaviors. Whether people manage their effort in a similar manner in audition remains unclear. As the listening performance of people with normal hearing often serves as the goal of auditory rehabilitation for people with hearing loss, this study evaluated how strategy-induced effort allocation, challenged by reward and task demand, interactively impacted auditory comprehension in normal hearing adults. DESIGN: A value-based strategic effort allocation paradigm was evaluated in 40 normal-hearing young adults. The paradigm included five levels of reward (motivation) and five levels of task demand (speech rate) that were independently manipulated. Effects of reward and task demand on performance accuracy and pupil dilation (a measure of auditory comprehension effort) were examined. RESULTS: There was a significant interaction effect of reward and task demand on both pupil dilation and comprehension accuracy. At the response stage of speech comprehension processing, pupil dilation significantly decreased as the task demand increased at high reward levels. In contrast, pupil dilation did not vary significantly as a function of task demand at low reward levels. Reward significantly improved performance accuracy at fast and extremely fast rate conditions, but not at the slower rates. CONCLUSIONS: Consistent with previous studies on effort regulation, reward and task demand appear to be associated with auditory comprehension effort allocation in an interactive manner when strategic effort control was required to achieve a reward goal. The young normal-hearing listeners in this study prioritized their effort to relatively easy task items over difficult ones at high levels of reward, suggesting a cost-effective value-based strategic effort allocation. Reward significantly improved task performance in terms of accuracy at difficult listening conditions. These findings support the incorporation of affective factors (e.g., reward) and the utility of the value-based strategic effort allocation paradigm in the experimental setting to understand how clinically relevant factors (such as hearing loss and age) might change strategic auditory comprehension behavior.

Genome-wide association meta-analysis identifies five novel loci for age-related hearing impairment.

Previous research has shown that genes play a substantial role in determining a person's susceptibility to age-related hearing impairment. The existing studies on this subject have different results, which may be caused by difficulties in determining the phenotype or the limited number of participants involved. Here, we have gathered the largest sample to date (discovery n = 9,675; replication n = 10,963; validation n = 356,141), and examined phenotypes that represented low/mid and high frequency hearing loss on the pure tone audiogram. We identified 7 loci that were either replicated and/or validated, of which 5 loci are novel in hearing. Especially the ILDR1 gene is a high profile candidate, as it contains our top SNP, is a known hearing loss gene, has been linked to age-related hearing impairment before, and in addition is preferentially expressed within hair cells of the inner ear. By verifying all previously published SNPs, we can present a paper that combines all new and existing findings to date, giving a complete overview of the genetic architecture of age-related hearing impairment. This is of importance as age-related hearing impairment is highly prevalent in our ageing society and represents a large socio-economic burden.

Parameters to maximize 2f2-f1 distortion product otoacoustic emission levels.

PURPOSE: Past research has established parameters for the 2f1-f2 distortion product otoacoustic emissions (DPOAEs) that enhance response levels (e.g., L1 - L2 = 10 dB; f2/f1 = 1.22; L1, L2 = 65, 55 dB SPL). These same parameters do not optimize 2f2-f1 DPOAEs. Therefore, this study was conducted to evaluate more completely those parameters that produce the most robust 2f2-f1 output. METHOD: Input-output functions of the 2f2-f1 component were obtained from 20 normal-hearing adults (with f2 = 2000 Hz and 4000 Hz). Frequency ratios, level differences, and overall sound levels were manipulated with parameter combinations chosen to expand on information established in previous studies. The DPOAE signal-to-noise ratio (SNR), response presence, and output levels were measured. RESULTS: In general, mean SNRs and 2f2-f1 levels were greater, and DPOAEs were present more often for 2000 than for 4000 Hz across all parameter combinations. No single parameter combination resulted in pronounced maxima for 2f2-f1, which is consistent with past studies but is in sharp contrast to results for the more familiar 2f1-f2. CONCLUSIONS: Overall, the results suggest that to maximize the 2f2-f1 level, lower test frequencies, low frequency ratio, essentially equal levels of primary tones, and moderate stimulus levels are best, and such parameters might be important for applying DPOAE measurement to assessment of normal and impaired auditory function.

Profound Hearing Loss: Addressing Barriers to Hearing Healthcare.

The impact of profound hearing loss on infants and adults is variable and greatly influenced by improved audition derived from hearing aids and cochlear implants. However, barriers to healthcare, hearing healthcare in particular, can offset the benefits provided by these sensory devices. Common barriers include cost, location, availability of trained professionals, acceptance of the hearing loss, language and cultural differences, secondary disabilities, and mental health issues. These barriers and their distinct presentations vary somewhat by age, language, and where people live (urban vs. rural), and can interfere with receiving testing and devices in a timely manner. They also can limit auditory, speech and language therapies, and interfere with acceptance of the hearing loss and devices. Rehabilitation should focus on eliminating or reducing the adverse impact of these barriers on patients and their families. Some of which can be done through professional training and multidisciplinary activities, counseling, and community outreach.

Audiological Assessment of Word Recognition Skills in Persons With Aphasia.

PURPOSE: The purpose of this study was to evaluate the ability of persons with aphasia, with and without hearing loss, to complete a commonly used open-set word recognition test that requires a verbal response. Furthermore, phonotactic probabilities and neighborhood densities of word recognition errors were assessed to explore potential underlying linguistic complexities that might differentially influence performance among groups. METHOD: Four groups of adult participants were tested: participants with no brain injury with normal hearing, participants with no brain injury with hearing loss, participants with brain injury with aphasia and normal hearing, and participants with brain injury with aphasia and hearing loss. The Northwestern University Auditory Test No. 6 (NU-6; Tillman & Carhart, 1966) was administered. Those participants who were unable to respond orally (repeating words as heard) were assessed with the Picture Identification Task (Wilson & Antablin, 1980), permitting a picture-pointing response instead. Error patterns from the NU-6 were assessed to determine whether phonotactic probability influenced performance. RESULTS: All participants with no brain injury and 72.7% of the participants with aphasia (24 out of 33) completed the NU-6. Furthermore, all participants who were unable to complete the NU-6 were able to complete the Picture Identification Task. There were significant group differences on NU-6 performance. The 2 groups with normal hearing had significantly higher scores than the 2 groups with hearing loss, but the 2 groups with normal hearing and the 2 groups with hearing loss did not differ from one another, implying that their performance was largely determined by hearing loss rather than by brain injury or aphasia. The neighborhood density, but not phonotactic probabilities, of the participants' errors differed across groups with and without aphasia. CONCLUSIONS: Because the vast majority of the participants with aphasia examined could be tested readily using an instrument such as the NU-6, clinicians should not be reticent to use this test if patients are able to repeat single words, but routine use of alternative tests is encouraged for populations of people with brain injuries.

Auditory performance characteristics of the Computerized Revised Token Test (CRTT).

PURPOSE: To assess the Computerized Revised Token Test (CRTT) performance of individuals with normal hearing under several intensity conditions and under several spectral and temporal perturbation conditions. METHOD: Sixty normal-hearing listeners were randomly assigned to 1 of 3 groups. Group 1 provided performance-intensity information about CRTT performance using uncompressed acoustic stimuli. Groups 2 and 3 completed the CRTT using temporally and spectrally compressed and expanded stimuli. CRTT performance functions were plotted for each group. RESULTS: Group 1 required minimal audibility to perform maximally on this task. As expected, Groups 2 and 3 showed significant differences across subtests, regardless of distortion condition. Mean differences in performance between successive conditions for Group 2 increased beyond 40% time compressed. There was 1 significant difference for the time-expanded condition. There were no differences across frequency compressed and expanded conditions. CONCLUSION: Young listeners require limited signal gain on the CRTT to achieve maximum performance. Time and frequency compression and expansion results were consistent with previous findings with varying types of speech stimuli. The results have implications for administration and interpretation of the CRTT administered to persons from other populations and will help in the development of a normative database for the CRTT.