Word Recognition In Noise Research Articles

Timing of bilateral sequential cochlear implantation for children: determination of its benefit.

To evaluate monosyllable word recognition in noise under different conditions in bilateral sequential cochlear implants (CIs). Second, to assess subjective hearing benefits among bilateral sequential CIs, bimodal hearing, and CI-only groups. Lastly, to analyze the prognostic factors affecting CI outcomes in children with bilateral sequential CIs. Sixty-five children with CI were enrolled. Mandarin monosyllable recognition tests in noise and the Speech, Spatial, and Qualities of Hearing Scale (SSQ) were used to assess post-CI outcomes. The SSQ benefits were compared among children with bilateral CIs, bimodal hearing, and CI-only. Bilateral CIs significantly outperformed the first or second CI alone using in noise. The bilateral CI group had significantly better SSQ scores for speech, qualities, and total scores compared to the CI-only group. Additionally, 41% of the variance in speech perception of the second CI can be attributed to the inter-implantation interval between bilateral CIs. Bilateral sequential CIs can enhance speech perception in noise and daily life-functioning for children. Earlier implantation of bilateral sequential CIs results in better outcomes, while inter-implantation interval exceeding 9.6 years between bilateral CIs may lead to poor second CI performance in noise. Therefore, early bilateral sequential CIs should be encouraged.

Protective face masks affect clearly produced diphthongs by L1 and L2 English talkers

The study investigated how the use of protective face masks and language experience shape the production of listener-oriented clear speech. One L1 and one L2 English talker read sentences in a clear and conversational speaking style with and without a surgical mask. Formant trajectories between the onset and offset of two diphthongs, /aɪ/ and /eɪ/, were analyzed using Euclidean distance in the F1–F2 vowel space. The results showed that the distance between the onset /a/ and the offset /ɪ/ was larger when speech was produced without the mask and when speaking clearly. These modifications were larger for L1 talker compared to the L2 talker. The Euclidian distance for /eɪ/was only affected by speaking style. The results suggest that talkers produced hyperarticulated diphthongs characterized by larger formant movements in clear speech. The presence of a mask limited jaw movement for the diphthong containing the low vowel. Additionally, the L1 talker made larger articulatory modifications in response to the presence of a mask and listener-oriented clear speech compared to the talker with less extensive experience with the target language. These production patterns may be related to lower word recognition in noise for masked, conversational, and L2 speech found in previous work.

The Effects of a Home Personal Computer-based Auditory Training Program on the Binaural Listening Skills of Children With Specific Learning Disability: A Protocol for a Randomized Clinical Trial

Background and Objectives: A high prevalence of central auditory processing disorders has been reported in children with learning disabilities. One of the crucial auditory processing disorders in these children is a binaural processing problem. Binaural hearing leads to improved auditory performance in noisy situations. This research aims to develop an auditory training program based on binaural interaction at the brainstem level and to investigate its effect on the binaural listening skills of children with a specific learning disability. Methods: After developing the rehabilitation program and determining its validity, this intervention study is conducted in three stages. The first stage includes baseline assessments, the second stage includes the implementation of rehabilitation intervention and the third stage consists of the re-implementation of the tests of the first stage once immediately after intervention and then once after 45 days of training. Masking level differences (MLD), Persian auditory recognition of words in noise (PARWIN), and binaural speech-auditory brainstem response (Speech-ABR) tests are the primary outcome measures. Persian randomized dichotic digits test (PRDDT), Persian pediatric competing word test (PPCWT), Persian pediatric competing sentences test (PPCST), and Persian version of the auditory processing disorder questionnaire (APDQ-P) were included as secondary outcome measures. The sample size in each intervention and control group was 15 people and the duration of training was 3 months. Conclusion: Considering the importance of brainstem function in binaural hearing, it is recommended to investigate the effectiveness of the developed binaural interaction training program in improving hearing in background noise in children with specific learning disabilities.

Speech perception in noise: no interaction between working memory and degree of speech degradation

ABSTRACT Speech recognition in noise (SiN) requires explicit cognitive resources such as working memory capacity (WMC). However, existing evidence on the role of WMC in SiN, especially for young adults with normal hearing, is mixed. This study aimed to systematically evaluate the role of WMC when the degree of speech recognition varied as a consequence of adding background noise of varying intensity levels. Specifically, the objective was to determine whether or not there was an effect of noise level on the recruitment of WMC during speech recognition tasks. Fifty-three young adults (18–37 years) with normal hearing were recruited and their ability to recognize speech in the presence of background noise was measured using sentences and words. Speech-to-noise ratios (SNRs) were varied from +10 to −10 dB SNR in 5 dB steps to manipulate the degree of speech recognition. Listeners’ WMC was also measured using two working memory tasks. A significant positive association between WMC and SiN was found for sentence recognition in noise. However, no significant interaction between WMC and SNR was found for isolated word and sentence recognition tasks. WMC was not found to be a significant predictor of word recognition in noise. These results suggests that for young normal hearing listeners, the recruitment of WMC during sentence recognition, especially in non-informational fluctuating noise, is not modulated by the SNR .

Auditory Processing in Musicians, a Cross-Sectional Study, as a Basis for Auditory Training Optimization.

Μusicians are reported to have enhanced auditory processing. This study aimed to assess auditory perception in Greek musicians with respect to their musical specialization and to compare their auditory processing with that of non-musicians. Auditory processing elements evaluated were speech recognition in babble, rhythmic advantage in speech recognition, short-term working memory, temporal resolution, and frequency discrimination threshold detection. All groups were of 12 participants. Three distinct experimental groups tested included western classical musicians, Byzantine chanters, and percussionists. The control group consisted of 12 non-musicians. The results revealed: (i) a rhythmic advantage for word recognition in noise for classical musicians (M = 12.42) compared to Byzantine musicians (M = 9.83), as well as for musicians compared to non-musicians (U = 120.50, p = 0.019), (ii) better frequency discrimination threshold of Byzantine musicians (M = 3.17, p = 0.002) compared to the other two musicians' group for the 2000 Hz region, (iii) statistically significant better working memory for musicians (U = 123.00, p = 0.025) compared to non-musicians. Musical training enhances elements of auditory processing and may be used as an additional rehabilitation approach during auditory training, focusing on specific types of music for specific auditory processing deficits.

Non-native disadvantage in spoken word recognition is due to lexical knowledge and not type/level of noise

Adverse listening conditions typically trigger the use of linguistic knowledge, which helps the listener compensate for the impoverished acoustic signal. It is not clear, however, whether linguistic knowledge facilitates non-native speech perception in the same way as it does native speech perception. This study examined how native listeners and non-native learners use distributional characteristics of the Mandarin lexicon for word recognition in noise. Monosyllabic Mandarin words varying in syllable token frequency and syllable-tone co-occurrence probabilities were mixed with speech-shaped noise and two-talker babble at two signal-to-noise ratios. Participants were asked to listen to the speech and type the perceived syllable and tone word. The results showed that two-talker babble was more disruptive than speech-shaped noise, and a lower signal-to-noise ratio was more detrimental than a higher signal-to-noise ratio. However, neither noise type or noise level affected non-native word recognition disproportionately. Syllable token frequency facilitated word recognition for both listener groups, but only the native listeners showed robust use of syllable-tone co-occurrence probabilities for word recognition. For all listeners, lexical proficiency correlated positively with word recognition performance. These results suggest that lexical proficiency accounts for the use of distributional knowledge regardless of the type or level of noise.

Auditory Electrophysiological and Perceptual Measures in Student Musicians with High Sound Exposure

This study aimed to determine (a) the influence of noise exposure background (NEB) on the peripheral and central auditory system functioning and (b) the influence of NEB on speech recognition in noise abilities in student musicians. Twenty non-musician students with self-reported low NEB and 18 student musicians with self-reported high NEB completed a battery of tests that consisted of physiological measures, including auditory brainstem responses (ABRs) at three different stimulus rates (11.3 Hz, 51.3 Hz, and 81.3 Hz), and P300, and behavioral measures including conventional and extended high-frequency audiometry, consonant-vowel nucleus-consonant (CNC) word test and AzBio sentence test for assessing speech perception in noise abilities at -9, -6, -3, 0, and +3 dB signal to noise ratios (SNRs). The NEB was negatively associated with performance on the CNC test at all five SNRs. A negative association was found between NEB and performance on the AzBio test at 0 dB SNR. No effect of NEB was found on the amplitude and latency of P300 and the ABR wave I amplitude. More investigations of larger datasets with different NEB and longitudinal measurements are needed to investigate the influence of NEB on word recognition in noise and to understand the specific cognitive processes contributing to the impact of NEB on word recognition in noise.

Building on the Academic Legacy of Pat Stelmachowicz and other Pioneers in Developmental Psychoacoustics and Pediatric Audiology: The Children's English/Spanish Speech Recognition Test (ChEgSS).

Basic research investigating auditory development often has implications for clinical diagnosis and treatment of hearing loss in children, but it can be challenging to translate those findings into practice. Meeting that challenge was a guiding principle of Pat Stelmachowicz's research and mentorship. Her example inspired many of us to pursue translational research and motivated the recent development of the Children's English/Spanish Speech Recognition Test (ChEgSS). This test evaluates word recognition in noise or two-talker speech, with target and masker speech produced in either English or Spanish. The test uses recorded materials and a forced-choice response, so the tester need not be fluent in the test language. ChEgSS provides a clinical measure of masked speech recognition outcomes for children who speak English, Spanish, or both, including estimates of performance in noise and two-talker speech, with the goal of maximizing speech and hearing outcomes for children with hearing loss. This article highlights several of Pat's many contributions to pediatric hearing research and describes the motivation and development of ChEgSS.

Predictive Processing and Inhibitory Control Drive Semantic Enhancements for Non-Dominant Language Word Recognition in Noise

Auditory word recognition in the non-dominant language has been suggested to break down under noisy conditions due, in part, to the difficulty of deriving a benefit from contextually constraining information. However, previous studies examining the effects of sentence constraints on word recognition in noise have conflated multiple psycholinguistic processes under the umbrella term of “predictability”. The present study improves on these by narrowing its focus specifically on prediction processes, and on whether the possibility of using semantic constraint to predict an upcoming target word improves word recognition in noise for different listener populations and noise conditions. We find that heritage, but not second language, Spanish listeners derive a word recognition-in-noise benefit from predictive processing, and that non-dominant language word recognition benefits more from predictive processing under conditions of energetic, rather than informational, masking. The latter suggests that managing interference from competing speech and generating predictions about an upcoming target word draw on the same cognitive resources. An analysis of individual differences shows that better inhibitory control ability is associated with reduced disruption from competing speech in the more dominant language in particular, revealing a critical role for executive function in simultaneously managing interference and generating expectations for upcoming words.

Change in Preferred Gain, Word Recognition Scores, and Sound Qualities as Hearing Aid Wearing Period

Purpose: The purpose of this study was to assess the changes in gain, aided threshold, word recognition in noise, and sound quality of hearing aids according to the first wearing period of sensorineural hearing loss (SNHL) to determine the rehabilitation goal and effective adjustments of the electroacoustic parameters. Methods: The subjects of this study were 17 SNHL (26 ears) who had no experience in wearing hearing aids, with an average age of 67.5 years, an average pure-tone average of 50.5 dB HL, an average WRS of 68.9%, and a K-IOI-HA (Korean version of International Outcome Inventory for Hearing Aids) score of 25 or higher. The procedure for gain adjustment of the hearing aid was through NAL-NL2 (National Acoustic Laboratories, non-linear version 2) at first adjustment and subjective responses of the subject afterwards. Real-ear insertion gain, aided threshold, WRS in noise, and sound quality evaluation were conducted at week 0 (initial fit), week 2, and week 6 (or final visit). Results: The study showed a higher gain in 55 dB sound pressure level at most frequencies and improved aided thresholds at 1,000 Hz and 2,000 Hz as the wearing period increased. WRS also increased in 10 dB and 5 dB signal-to-noise ratios, and the sharpness, occlusion, and loudness of noise were shown to improve despite the increased gain. Conclusion: Despite the limitation of gain change with the wearing period, the results of this study expect to aid in setting rehabilitation goals according to the wearing period and adjusting electroacoustic parameters.

The effects of noise exposure and aging on the acoustic reflex in normal-hearing people

Noise exposure and aging can cause subclinical hearing problems that are not identified with conventional audiometry. Nerve damage among the normal hearing could reduce afferent auditory-nerve activity consequently reducing the middle ear muscle reflex (MEMR). It was hypothesized that normal-hearing individuals reporting more noise exposure would have slower growth of MEMR with increasing levels. Data were analyzed from sixty-one young, normal-hearing people. Each completed the four MEMR assessments and the Life-Time Exposure to Noise and Solvents Questionnaire. Reflex amplitudes were measured as a function of sound level using clinical equipment. High-pass noise stimuli (1.5-4.0 kHz) and a 1-KHz tone were used as elicitors with a 226-Hz probe tone. Data were analyzed using a linear mixed effects model. Individuals reporting higher noise exposure with the LENS-Q had significantly reduced growth of MEMR with level, supporting the hypothesis. Independent effects of age and gender were also observed. The effect of the pure-tone average on MEMR growth functions did not reach significance at the 5% level (p = 0.052). No significant relationships were observed between the MEMR measures and extended high-frequency thresholds nor with word recognition in noise. The results suggest that the MEMR could indicate subclinical nerve damage.

Evidence for cortical adjustments to perceptual decision criteria during word recognition in noise

Extensive increases in cingulo-opercular frontal activity are typically observed during speech recognition in noise tasks. This elevated activity has been linked to a word recognition benefit on the next trial, termed “adaptive control,” but how this effect might be implemented has been unclear. The established link between perceptual decision making and cingulo-opercular function may provide an explanation for how those regions benefit subsequent word recognition. In this case, processes that support recognition such as raising or lowering the decision criteria for more accurate or faster recognition may be adjusted to optimize performance on the next trial. The current neuroimaging study tested the hypothesis that pre-stimulus cingulo-opercular activity reflects criterion adjustments that determine how much information to collect for word recognition on subsequent trials. Participants included middle-age and older adults (N = 30; age = 58.3 ± 8.8 years; m ± sd) with normal hearing or mild sensorineural hearing loss. During a sparse fMRI experiment, words were presented in multitalker babble at +3 dB or +10 dB signal-to-noise ratio (SNR), which participants were instructed to repeat aloud. Word recognition was significantly poorer with increasing participant age and lower SNR compared to higher SNR conditions. A perceptual decision-making model was used to characterize processing differences based on task response latency distributions. The model showed that significantly less sensory evidence was collected (i.e., lower criteria) for lower compared to higher SNR trials. Replicating earlier observations, pre-stimulus cingulo-opercular activity was significantly predictive of correct recognition on a subsequent trial. Individual differences showed that participants with higher criteria also benefitted the most from pre-stimulus activity. Moreover, trial-level criteria changes were significantly linked to higher versus lower pre-stimulus activity. These results suggest cingulo-opercular cortex contributes to criteria adjustments to optimize speech recognition task performance.

The effects of stimulus modality, task complexity, and cuing on working memory and the relationship with speech recognition in older cochlear implant users

IntroductionThe role of working memory (WM) in speech recognition of older cochlear implant (CI) users remains unclear. This study 1) examined the effects of aging and CI on WM performance across different modalities (auditory vs. visual) and cuing conditions, and 2) assessed how specific WM measures relate to sentence and word recognition in noise. MethodFourteen Older CI users, 12 Older acoustic-hearing (AH) listeners with age-appropriate hearing loss, and 15 Young normal-hearing (NH) listeners were tested. Participants completed two simple span tasks (auditory digit and visual letter span), two complex WM tasks (reading span and cued-modality WM with simultaneously presented auditory digits and visual letters), and two speech recognition tasks (sentence and word recognition in speech-babble noise). ResultsThe groups showed similar simple span performance, except that Older CI users had lower auditory digit span than Young NH listeners. Both older groups had similar reading span performance, but scored significantly lower than Young NH listeners, indicating age-related declines in attentional and phonological processing. A similar group effect was observed in the cued-modality WM task. All groups showed higher recall for auditory digits than for visual letters and the advantage was most evident without modality cuing. All groups displayed greater cuing benefits for visual recall than for auditory recall, suggesting that participants consistently allocated more attention to auditory stimuli regardless of cuing. For Older CI users, after controlling for the previously reported spectral resolution, auditory-uncued WM performance was significantly correlated with word recognition but not sentence recognition. ConclusionsComplex WM was significantly affected by aging but not by CI. Neither aging nor CI significantly affected modality cuing benefits in the WM task. For Older CI users, complex auditory WM with attentional control may better reflect the cognitive load of speech recognition in noise than simple span or complex visual WM.

Cochlear Implants in Single-Sided Deafness. Comparison Between Children and Adult Populations With Post-lingually Acquired Severe to Profound Hearing Loss

Objective: To determine audiological and clinical results of cochlear implantation (CI) comparing two populations with single-sided deafness (SSD): post-lingually deaf children between 6 and 12 years of age, and post-lingually deaf adults, in order to evaluate the effect of CI in different age groups.Design: Retrospective case review.Setting: Tertiary clinic.Patients and Method: Twenty-three children and twenty-one adult patients that were candidates for CI with single-side deafness were included. In all cases we evaluate: Speech perception thresholds; disyllabic words test (65 dB SPL) were performed in the modalities S0–SCI–SNH and Auditory Lateralization Test. The Speech, Spatial, and Qualities of Hearing Scale (SSQ) questionnaire was also used. All results were obtained after 12 months of CI activation.Results: In children, the most common etiology was idiopathic sensory-neural hearing loss. They showed positive results in the Auditory Lateralization Test. In the Speech Test, word recognition in noise improved from 2% preoperatively to 61.1% at a mean follow-up of 1 year (S0 condition) in children [test with signal in CI side 60% and signal normal hearing side (plugged) 31%]. The processor was used for >12 h in all cases. With respect to the SSQ questionnaire, parents were more satisfied within the postoperative period than within the preoperative period. For adults, the most common etiology was idiopathic sudden sensorineural hearing loss (SNHL). Positive results in the Auditory Lateralization Test were found. With respect to the Speech Test in quiet conditions: Word recognition in noise improved from 5.7% preoperatively to 71.8% at a mean follow-up of 1 year [test with signal in CI side 68% and signal normal hearing side (plugged) 41%]. The processor was used for >12 h. In the SSQ questionnaire, the post-operative results showed a beneficial effect of the CI. No adverse events were reported during the study period. No differences were found between children and adults in all tests in this study.Conclusions: Cochlear implantation in post-lingually deaf adults and children with SSD can achieve a speech perception outcome comparable with CI in conventional candidates. Improvements in spatial hearing were also observed. Careful patient selection and counseling regarding potential benefits are important to optimize outcomes.

Identifying Subclinical Hearing Loss: Extended Audiometry and Word Recognition in Noise

Introduction: Normal-hearing people often have complaints about the ability to recognize speech in noise. Such disabilities are not typically assessed with conventional audiometry. Suprathreshold temporal deficits might contribute to reduced word recognition in noise as well as reduced temporally based binaural release of masking for speech. Extended high-frequency audibility (>8 kHz) has also been shown to contribute to speech perception in noise. The primary aim of this study was to compare conventional audiometric measures with measures that could reveal subclinical deficits. Methods: Conventional and extended high-frequency audiometry was done with 119 normal-hearing people ranging in age from 18 to 72. The ability to recognize words in noise was evaluated with and without differences in temporally based spatial cues. A low-uncertainty, closed-set word recognition task was used to limit cognitive influences. Results: In normal-hearing listeners, word recognition in noise ability decreases significantly with increasing pure-tone average (PTA). On average, signal-to-noise ratios worsened by 5.7 and 6.0 dB over the normal range, for the diotic and dichotic conditions, respectively. When controlling for age, a significant relationship remained in the diotic condition. Measurement error was estimated at 1.4 and 1.6 dB for the diotic and dichotic conditions, respectively. Controlling for both PTA and age, EHF-PTAs showed significant partial correlations with SNR50 in both conditions (ρ = 0.30 and 0.23). Temporally based binaural release of masking worsened with age by 1.94 dB from 18 to 72 years old but showed no significant relationship with either PTA. Conclusions: All three assessments in this study demonstrated hearing problems independently of those observed in conventional audiometry. Considerable degradations in word recognition in noise abilities were observed as PTAs increased within the normal range. The use of an efficient words-in-noise measure might help identify functional hearing problems for individuals that are traditionally normal hearing. Extended audiometry provided additional predictive power for word recognition in noise independent of both the PTA and age. Temporally based binaural release of masking for word recognition decreased with age independent of PTAs within the normal range, indicating multiple mechanisms of age-related decline with potential clinical impact.

Spectral Modulation Detection Performance and Speech Perception in Pediatric Cochlear Implant Recipients.

The aims of this study were, for pediatric cochlear implant (CI) recipients, (a) to determine the effect of age on their spectral modulation detection (SMD) ability and compare their age effect to that of their typically hearing (TH) peers; (b) to identify demographic, cognitive, and audiological factors associated with SMD ability; and (c) to determine the unique contribution of SMD ability to segmental and suprasegmental speech perception performance. A total of 104 pediatric CI recipients and 38 TH peers (ages 6-11 years) completed a test of SMD. CI recipients completed tests of segmental (e.g., word recognition in noise and vowels and consonants in quiet) and suprasegmental (e.g., talker discrimination, stress discrimination, and emotion identification) perception, nonverbal intelligence, and working memory. Regressions analyses were used to examine the effects of group and age on percent-correct SMD scores. For the CI group, the effects of demographic, audiological, and cognitive variables on SMD performance and the effects of SMD on speech perception were examined. The TH group performed significantly better than the CI group on SMD. Both groups showed better performance with increasing age. Significant predictors of SMD performance for the CI group were age and nonverbal intelligence. SMD performance predicted significant variance in segmental and suprasegmental perception. The variance predicted by SMD performance was nearly double for suprasegmental than for segmental perception. Children in the CI group, on average, scored lower than their TH peers. The slopes of improvement in SMD with age did not differ between the groups. The significant effect of nonverbal intelligence on SMD performance in CI recipients indicates that difficulties inherent in the task affect outcomes. SMD ability predicted speech perception scores, with a more prominent role in suprasegmental than in segmental speech perception. SMD ability may provide a useful nonlinguistic tool for predicting speech perception benefit, with cautious interpretation based on age and cognitive function.

Identifying subclinical hearing problems

Noise exposure and aging can cause subclinical hearing problems that are not identified with conventional audiometry. Potential clinical assessments were studied that could identify subclinical hearing deterioration: (1) Electrocochleography (ECoG); (2) Middle Ear Muscle Reflex (MEMR); (3) Extended High Frequency (EHF) thresholds (10–16 kHz); and (4) word recognition in noise. Sixty-one young, normal-hearing people were recruited. Each completed the four auditory assessments and the Life-Time Exposure to Noise Solvents Questionnaire (LENS-Q). ECoG and MEMR measurements were measured as a function of sound level using clinical equipment. Word recognition in noise was measured with a diotic, closed-set, 12-alternative spondees-in-noise test. It was hypothesized that normal-hearing individuals reporting more noise exposure would have slower growth of the ECoG measures and MEMR magnitudes with increasing levels. Individuals reporting higher noise exposure with the LENS-Q had significantly reduced MEMR magnitudes and smaller slopes, supporting the hypothesis. Gender effects were observed. No significant effect of self-report noise-exposure was seen with ECoG AP growth functions or SP/AP ratios, though modest age effects were observed. EHF thresholds were the only significant predictor of word recognition in noise. The results suggest that word recognition in noise, EHF audiometry, and MEMR could indicate subclinical hearing problems.

A comparison of monolingual and bilingual toddlers' word recognition in noise.

The purpose of this study was to examine whether differences in language exposure (i.e., being raised in a bilingual versus a monolingual environment) influence young children's ability to comprehend words when speech is heard in the presence of background noise. Forty-four children (22 monolinguals and 22 bilinguals) between the ages of 29 and 31 months completed a preferential looking task where they saw picture-pairs of familiar objects (e.g., balloon and apple) on a screen and simultaneously heard sentences instructing them to locate one of the objects (e.g., look at the apple!). Speech was heard in quiet and in the presence of competing white noise. Children's eye-movements were coded off-line to identify the proportion of time they fixated on the correct object on the screen and performance across groups was compared using a 2 × 3 mixed analysis of variance. Bilingual toddlers performed worse than monolinguals during the task. This group difference in performance was particularly clear when the listening condition contained background noise. There are clear differences in how infants and adults process speech in noise. To date, developmental work on this topic has mainly been carried out with monolingual infants. This study is one of the first to examine how background noise might influence word identification in young bilingual children who are just starting to acquire their languages. High noise levels are often reported in daycares and classrooms where bilingual children are present. Therefore, this work has important implications for learning and education practices with young bilinguals.

Second‐language word recognition in noise: Interdependent neuromodulatory effects of semantic context and crosslinguistic interactions driven by word form similarity

Spoken language comprehension is a fundamental component of our cognitive skills. We are quite proficient at deciphering words from the auditory input despite the fact that the speech we hear is often masked by noise such as background babble originating from talkers other than the one we are attending to. To perceive spoken language as intended, we rely on prior linguistic knowledge and context. Prior knowledge includes all sounds and words that are familiar to a listener and depends on linguistic experience. For bilinguals, the phonetic and lexical repertoire encompasses two languages, and the degree of overlap between word forms across languages affects the degree to which they influence one another during auditory word recognition. To support spoken word recognition, listeners often rely on semantic information (i.e., the words we hear are usually related in a meaningful way). Although the number of multilinguals across the globe is increasing, little is known about how crosslinguistic effects (i.e., word overlap) interact with semantic context and affect the flexible neural systems that support accurate word recognition. The current multi-echo functional magnetic resonance imaging (fMRI) study addresses this question by examining how prime-target word pair semantic relationships interact with the target word's form similarity (cognate status) to the translation equivalent in the dominant language (L1) during accurate word recognition of a non-dominant (L2) language. We tested 26 early-proficient Spanish-Basque (L1-L2) bilinguals. When L2 targets matching L1 translation-equivalent phonological word forms were preceded by unrelated semantic contexts that drive lexical competition, a flexible language control (fronto-parietal-subcortical) network was upregulated, whereas when they were preceded by related semantic contexts that reduce lexical competition, it was downregulated. We conclude that an interplay between semantic and crosslinguistic effects regulates flexible control mechanisms of speech processing to facilitate L2 word recognition, in noise.

Psychometric function for speech-in-noise tests accounts for word-recognition deficits in older listeners.

Speech-in-noise (SIN) understanding in older age is affected by hearing loss, impaired central auditory processing, and cognitive deficits. SIN-tests measure these factors' compound effects by a speech reception threshold, defined as the signal-to-noise ratio required for 50% word understanding (SNR50). This study compared two standard SIN tests, QuickSIN (n = 354) in young and older adults and BKB-SIN (n = 139) in older adults (>60 years). The effects of hearing loss and age on SIN understanding were analyzed to identify auditory and nonauditory contributions to SIN loss. Word recognition in noise was modelled with individual psychometric functions using a logistic fit with three parameters: the midpoint (SNRα), slope (β), and asymptotic word-recognition deficit at high SNR (λ). The parameters SNRα and λ formally separate SIN loss into two components. SNRα characterizes the steep slope of the psychometric function at which a slight SNR increase provides a considerable improvement in SIN understanding. SNRα was discussed as being predominantly affected by audibility and low-level central auditory processing. The parameter λ describes a shallow segment of the psychometric function at which a further increase in the SNR provides modest improvement in SIN understanding. Cognitive factors in aging may contribute to the SIN loss indicated by λ.