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.

Effects of Stimulus Type on 16-kHz Detection Thresholds.

OBJECTIVES: Audiometric testing typically does not include frequencies above 8 kHz. However, recent research suggests that extended high-frequency (EHF) sensitivity could affect hearing in natural communication environments. Clinical assessment of hearing often employs pure tones and frequency-modulated (FM) tones interchangeably regardless of frequency. The present study was designed to evaluate how the stimulus chosen to measure EHF thresholds affects estimates of hearing sensitivity. DESIGN: The first experiment used standard audiometric procedures to measure 8- and 16-kHz thresholds for 5- to 28-year olds with normal hearing in the standard audiometric range (250 to 8000 Hz). Stimuli were steady tones, pulsed tones, and FM tones. The second experiment tested 18- to 28-year olds with normal hearing in the standard audiometric range using psychophysical procedures to evaluate how changes in sensitivity as a function of frequency affect detection of stimuli that differ with respect to bandwidth, including bands of noise. Thresholds were measured using steady tones, pulsed tones, FM tones, narrow bands of noise, and one-third-octave bands of noise at a range of center frequencies in one ear. RESULTS: In experiment 1, thresholds improved with increasing age at 8 kHz and worsened with increasing age at 16 kHz. Thresholds for individual participants were relatively similar for steady, pulsed, and FM tones at 8 kHz. At 16 kHz, mean thresholds were approximately 5 dB lower for FM tones than for steady or pulsed tones. This stimulus effect did not differ as a function of age. Experiment 2 replicated this greater stimulus effect at 16 kHz than at 8 kHz and showed that the slope of the audibility curve accounted for these effects. CONCLUSIONS: Contrary to prior expectations, there was no evidence that the choice of stimulus type affected school-age children more than adults. For individual participants, audiometric thresholds at 16 kHz were as much as 20 dB lower for FM tones than for steady tones. Threshold differences across stimuli at 16 kHz were predicted by differences in audibility across frequency, which can vary markedly between listeners. These results highlight the importance of considering spectral width of the stimulus used to evaluate EHF thresholds.

Can Closed-Set Word Recognition Differentially Assess Vowel and Consonant Perception for School-Age Children With and Without Hearing Loss?

PURPOSE: Vowels and consonants play different roles in language acquisition and speech recognition, yet standard clinical tests do not assess vowel and consonant perception separately. As a result, opportunities for targeted intervention may be lost. This study evaluated closed-set word recognition tests designed to rely predominantly on either vowel or consonant perception and compared results with sentence recognition scores. METHOD: Participants were children (5-17 years of age) and adults (18-38 years of age) with normal hearing and children with sensorineural hearing loss (7-17 years of age). Speech reception thresholds (SRTs) were measured in speech-shaped noise. Children with hearing loss were tested with their hearing aids. Word recognition was evaluated using a three-alternative forced-choice procedure, with a picture-pointing response; monosyllabic target words varied with respect to either consonant or vowel content. Sentence recognition was evaluated for low- and high-probability sentences. In a subset of conditions, stimuli were low-pass filtered to simulate a steeply sloping hearing loss in participants with normal hearing. RESULTS: Children's SRTs improved with increasing age for words and sentences. Low-pass filtering had a larger effect for consonant-variable words than vowel-variable words for both children and adults with normal hearing, consistent with the greater high-frequency content of consonants. Children with hearing loss tested with hearing aids tended to perform more poorly than age-matched children with normal hearing, particularly for sentence recognition, but consonant- and vowel-variable word recognition did not appear to be differentially affected by the amount of high- and low-frequency hearing loss. CONCLUSIONS: Closed-set recognition of consonant- and vowel-variable words appeared to differentially evaluate vowel and consonant perception but did not vary by configuration of hearing loss in this group of pediatric hearing aid users. Word scores obtained in this manner do not fully characterize the auditory abilities necessary for open-set sentence recognition, but they do provide a general estimate.

Maturation of Speech-in-Speech Recognition for Whispered and Voiced Speech.

PURPOSE: Some speech recognition data suggest that children rely less on voice pitch and harmonicity to support auditory scene analysis than adults. Two experiments evaluated development of speech-in-speech recognition using voiced speech and whispered speech, which lacks the harmonic structure of voiced speech. METHOD: Listeners were 5- to 7-year-olds and adults with normal hearing. Targets were monosyllabic words organized into three-word sets that differ in vowel content. Maskers were two-talker or one-talker streams of speech. Targets and maskers were recorded by different female talkers in both voiced and whispered speaking styles. For each masker, speech reception thresholds (SRTs) were measured in all four combinations of target and masker speech, including matched and mismatched speaking styles for the target and masker. RESULTS: Children performed more poorly than adults overall. For the two-talker masker, this age effect was smaller for the whispered target and masker than for the other three conditions. Children's SRTs in this condition were predominantly positive, suggesting that they may have relied on a wholistic listening strategy rather than segregating the target from the masker. For the one-talker masker, age effects were consistent across the four conditions. Reduced informational masking for the one-talker masker could be responsible for differences in age effects for the two maskers. A benefit of mismatching the target and masker speaking style was observed for both target styles in the two-talker masker and for the voiced targets in the one-talker masker. CONCLUSIONS: These results provide no compelling evidence that young school-age children and adults are differentially sensitive to the cues present in voiced and whispered speech. Both groups benefit from mismatches in speaking style under some conditions. These benefits could be due to a combination of reduced perceptual similarity, harmonic cancelation, and differences in energetic masking.

Face Masks Impact Auditory and Audiovisual Consonant Recognition in Children With and Without Hearing Loss.

Teachers and students are wearing face masks in many classrooms to limit the spread of the coronavirus. Face masks disrupt speech understanding by concealing lip-reading cues and reducing transmission of high-frequency acoustic speech content. Transparent masks provide greater access to visual speech cues than opaque masks but tend to cause greater acoustic attenuation. This study examined the effects of four types of face masks on auditory-only and audiovisual speech recognition in 18 children with bilateral hearing loss, 16 children with normal hearing, and 38 adults with normal hearing tested in their homes, as well as 15 adults with normal hearing tested in the laboratory. Stimuli simulated the acoustic attenuation and visual obstruction caused by four different face masks: hospital, fabric, and two transparent masks. Participants tested in their homes completed auditory-only and audiovisual consonant recognition tests with speech-spectrum noise at 0 dB SNR. Adults tested in the lab completed the same tests at 0 and/or -10 dB SNR. A subset of participants from each group completed a visual-only consonant recognition test with no mask. Consonant recognition accuracy and transmission of three phonetic features (place of articulation, manner of articulation, and voicing) were analyzed using linear mixed-effects models. Children with hearing loss identified consonants less accurately than children with normal hearing and adults with normal hearing tested at 0 dB SNR. However, all the groups were similarly impacted by face masks. Under auditory-only conditions, results were consistent with the pattern of high-frequency acoustic attenuation; hospital masks had the least impact on performance. Under audiovisual conditions, transparent masks had less impact on performance than opaque masks. High-frequency attenuation and visual obstruction had the greatest impact on place perception. The latter finding was consistent with the visual-only feature transmission data. These results suggest that the combination of noise and face masks negatively impacts speech understanding in children. The best mask for promoting speech understanding in noisy environments depend on whether visual cues will be accessible: hospital masks are best under auditory-only conditions, but well-fit transparent masks are best when listeners have a clear, consistent view of the talker's face.

Valid Acoustic Models of Cochlear Implants: One Size Does Not Fit All.

HYPOTHESIS: This study tests the hypothesis that it is possible to find tone or noise vocoders that sound similar and result in similar speech perception scores to a cochlear implant (CI). This would validate the use of such vocoders as acoustic models of CIs. We further hypothesize that those valid acoustic models will require a personalized amount of frequency mismatch between input filters and output tones or noise bands. BACKGROUND: Noise or tone vocoders have been used as acoustic models of CIs in hundreds of publications but have never been convincingly validated. METHODS: Acoustic models were evaluated by single-sided deaf CI users who compared what they heard with the CI in one ear to what they heard with the acoustic model in the other ear. We evaluated frequency-matched models (both all-channel and 6-channel models, both tone and noise vocoders) as well as self-selected models that included an individualized level of frequency mismatch. RESULTS: Self-selected acoustic models resulted in similar levels of speech perception and similar perceptual quality as the CI. These models also matched the CI in terms of perceived intelligibility, harshness, and pleasantness. CONCLUSION: Valid acoustic models of CIs exist, but they are different from the models most widely used in the literature. Individual amounts of frequency mismatch may be required to optimize the validity of the model. This may be related to the basalward frequency mismatch experienced by postlingually deaf patients after cochlear implantation.

A Simplified Approach to Quantifying a Child's Bilingual Language Experience.

Purpose Bilingual children's linguistic experience can vary markedly from child to child. For appropriate audiological assessment and intervention, audiologists need accurate and efficient ways to describe and understand a bilingual child's dynamic linguistic experience. This report documents an approach for quantitatively capturing a child's language exposure and usage in a time-efficient manner. Method A well-known pediatric bilingual language survey was administered to 83 parents of bilingual children, obtaining information about the child's exposure to (input) and usage of (output) Spanish and English for seventeen 1-hr intervals during a typical weekday and weekend day. Results A factor analysis indicated that capturing linguistic exposure and usage over three grouped-time intervals during a typical weekday and weekend day accounted for ≥ 74% of the total variance of the linguistic information captured with the full-length survey. Conclusions Although further confirmation is required, these results suggest that collecting language exposure and usage data from parents of bilingual children for three grouped-time intervals provides similar information as a comprehensive hour-by-hour approach. A time-efficient method of capturing the dynamic bilingual linguistic experience of a child would benefit pediatric audiologists and speech-language pathologists alike.

Cognitive and Linguistic Contributions to Masked Speech Recognition in Children.

Purpose The goal of this study was to examine the effects of cognitive and linguistic skills on masked speech recognition for children with normal hearing in three different masking conditions: (a) speech-shaped noise (SSN), (b) amplitude-modulated SSN (AMSSN), and (c) two-talker speech (TTS). We hypothesized that children with better working memory and language skills would have better masked speech recognition than peers with poorer skills in these areas. Selective attention was predicted to affect performance in the TTS masker due to increased cognitive demands from informational masking. Method A group of 60 children in two age groups (5- to 6-year-olds and 9- to 10-year-olds) with normal hearing completed sentence recognition in SSN, AMSSN, and TTS masker conditions. Speech recognition thresholds for 50% correct were measured. Children also completed standardized measures of language, memory, and executive function. Results Children's speech recognition was poorer in the TTS relative to the SSN and AMSSN maskers. Older children had lower speech recognition thresholds than younger children for all masker conditions. Greater language abilities were associated with better sentence recognition for the younger children in all masker conditions, but there was no effect of language for older children. Better working memory and selective attention skills were associated with better masked sentence recognition for both age groups, but only in the TTS masker condition. Conclusions The decreasing influence of vocabulary on masked speech recognition for older children supports the idea that this relationship depends on an interaction between the language level of the stimuli and the listener's vocabulary. Increased cognitive demands associated with perceptually isolating the target talker and two competing masker talkers with a TTS masker may result in the recruitment of working memory and selective attention skills, effects that were not observed in SSN or AMSSN maskers. Future research should evaluate these effects across a broader range of stimuli or with children who have hearing loss.

Speech Perception Changes in the Acoustically Aided, Nonimplanted Ear after Cochlear Implantation: A Multicenter Study.

In recent years there has been an increasing percentage of cochlear implant (CI) users who have usable residual hearing in the contralateral, nonimplanted ear, typically aided by acoustic amplification. This raises the issue of the extent to which the signal presented through the cochlear implant may influence how listeners process information in the acoustically stimulated ear. This multicenter retrospective study examined pre- to postoperative changes in speech perception in the nonimplanted ear, the implanted ear, and both together. Results in the latter two conditions showed the expected increases, but speech perception in the nonimplanted ear showed a modest yet meaningful decrease that could not be completely explained by changes in unaided thresholds, hearing aid malfunction, or several other demographic variables. Decreases in speech perception in the nonimplanted ear were more likely in individuals who had better levels of speech perception in the implanted ear, and in those who had better speech perception in the implanted than in the nonimplanted ear. This raises the possibility that, in some cases, bimodal listeners may rely on the higher quality signal provided by the implant and may disregard or even neglect the input provided by the nonimplanted ear.

Masked English Speech Recognition Performance in Younger and Older Spanish-English Bilingual and English Monolingual Children.

Purpose The purpose of this study was to compare masked English speech recognition thresholds between Spanish-English bilingual and English monolingual children and to evaluate effects of age, maternal education, and English receptive language abilities on individual differences in masked speech recognition. Method Forty-three Spanish-English bilingual children and 42 English monolingual children completed an English sentence recognition task in 2 masker conditions: (a) speech-shaped noise and (b) 2-talker English speech. Two age groups of children, younger (5-6 years) and older (9-10 years), were tested. The predictors of masked speech recognition performance were evaluated using 2 mixed-effects regression models. In the 1st model, fixed effects were age group (younger children vs. older children), language group (bilingual vs. monolingual), and masker type (speech-shaped noise vs. 2-talker speech). In the 2nd model, the fixed effects of receptive English vocabulary scores and maternal education level were also included. Results Younger children performed more poorly than older children, but no significant difference in masked speech recognition was observed between bilingual and monolingual children for either age group when English proficiency and maternal education were also included in the model. English language abilities fell within age-appropriate norms for both groups, but individual children with larger receptive vocabularies in English tended to show better recognition; this effect was stronger for younger children than for older children. Speech reception thresholds for all children were lower in the speech-shaped noise masker than in the 2-talker speech masker. Conclusions Regardless of age, similar masked speech recognition was observed for Spanish-English bilingual and English monolingual children tested in this study when receptive English language abilities were accounted for. Receptive English vocabulary scores were associated with better masked speech recognition performance for both bilinguals and monolinguals, with a stronger relationship observed for younger children than older children. Further investigation involving a Spanish-dominant bilingual sample is warranted given the high English language proficiency of children included in this study.

Language Proficiency and Dominance Considerations When Working With Spanish-English Bilingual Adults.

Purpose As the Hispanic population continues to increase within the United States, there is a pressing need to incorporate rigorous and efficient clinical assessments of language dominance and proficiency when working with Spanish-English bilingual patients. The purpose of this study was to begin addressing this need by evaluating the association between language dominance and language proficiency. Method The association between scores for the English Versant Test (Pearson Education, 2010), an automated assessment of spoken language proficiency, and dominance and proficiency scores obtained using the Bilingual Language Profile, a self-report questionnaire was evaluated. Results The results indicated that half of the variance in the English Versant Test was explained by the response to a single question included in the Bilingual Language Profile. Conclusion These data support the inclusion of asking patients to not only indicate how many languages they speak but, for those patients that speak more than 1 language, to also ask how well they understand each of the languages.