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Objectives: This study investigated the influence of long-term talker familiarity on speech-in-speech recognition in school-age children, with a specific emphasis on the role of familiarity with the mother's voice as either the target or masker speech. Design: Open-set sentence recognition was measured adaptively in a two-talker masker. Target and masker sentences were recorded by the adult mothers of the child participants. Each child heard sentences spoken by three adult female voices during testing; their own mother's voice (familiar voice) and two unfamiliar adult female voices. Study sample: Twenty-four school age children (8-13 years) with normal hearing. Results: When the target speech was spoken by a familiar talker (the mother), speech recognition was significantly better compared to when the target was unfamiliar. When the masker was spoken by the familiar talker, there was no difference in performance relative to the unfamiliar masker condition. Across all conditions, younger children required a more favorable signal-to-noise ratio than older children. Conclusion: Implicit long-term familiarity with a talker consistently improves children's speech-in-speech recognition across the age range tested, specifically when the target talker is familiar. However, performance remains unaffected by masker talker familiarity. Additionally, while target familiarity is advantageous, it does not entirely eliminate children's increased susceptibility to competing speech.

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BACKGROUND: Long-term assessments of children with cochlear implants (CI) are important inputs to help guide families and professionals in therapeutic and counselling processes. Based on these premises, the primary aim of the present study was to assess the long-term speech and language outcomes in a sample of prelingually deaf or hard of hearing (DHH) adolescents and young adults with unilateral or bilateral implantation in childhood. The secondary aim was to investigate the correlations of age at implantation with long-term speech and language outcomes. MATERIALS AND METHODS: Retrospective observational study on 54 long-term CI users, 33 unilateral and 21 bilateral (mean age at CI surgery 38.1 ± 24.6 months; mean age at last follow-up assessment 19.1 ± 4.3 years of age and mean follow-up time 16 ± 3.7 years). Means and standards were used to describe speech perception (in quiet, in fixed noise and in adaptive noise using It-Matrix) and morphosyntactic comprehension (TROG-2) outcomes. A univariate analysis was used to evaluate outcome differences between unilateral and bilateral patients. Bivariate analysis was performed to investigate the relationships between age at CI, audiological variables, and language outcomes. Finally, multivariate analysis was performed to quantify the relationship between It-Matrix, sentence recognition in quiet and at SNR+10 and TROG-2. RESULTS: The participants showed good speech recognition performance in quiet (94% for words and 89% for sentences) whilst their speech-in-noise scores decreased significantly. For the It-Matrix, only 9.2% of the participants showed scores within the normative range. This value was 60% for TROG-2 performance. For both auditory and language skills, group differences for unilateral versus bilateral CI users were not statistically significant (p > 0.05). Bivariate analysis showed that age at CI correlated significantly with overall results at TROG-2 (r = -0.6; p < 0.001) and with It-Matrix (r = 0.5; p < 0.001). TROG-2 was negatively correlated with results for It-Matrix (r = -0.5; p < 0.001). In the multivariate analysis with It-Matrix as a dependent variable, the model explained 63% of the variance, of which 60% was related to sentence recognition and 3% to morphosyntax. CONCLUSIONS: These data contribute to the definition of average long-term outcomes expected in subjects implanted during childhood whilst increasing our knowledge of the effects of variables such as age at CI and morphosyntactic comprehension on speech perception. Although the majority of this prelingually DHH cohort did not achieve scores within a normative range, remarkably better It-Matrix scores were observed when compared to those from postlingually deafened adult CI users.

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OBJECTIVE: The "Marginal benefit from acoustic amplification" version 2 (MBAA2) sentence test has been used in France in the routine evaluation of cochlear implant (CI) users for 20 years. Here we present four studies that characterise and validate the test, and compare it with the French matrix sentence test. DESIGN AND SAMPLE: An analytic method was developed to obtain speech recognition threshold in noise (SNR50) from testing at a fixed signal to noise ratios (SNRs). Speech recognition was measured at several fixed SNRs in 18 normal-hearing listeners and 15 CI listeners. Then, the test-retest reliability of the MBAA2 was measured in an additional 15 CI listeners. Finally, list equivalence was evaluated in eight CI listeners. RESULTS: The MBAA2 test produced lower SNR50s and SNR50s were obtained in more CI listeners than with the French matrix test. For the MBAA2, the standard deviation of test-retest differences in CI listeners was around 1 dB SNR. Three lists had deviant difficulty and nine low item-to-total correlations. CONCLUSIONS: We propose to reduce the number of MBAA2 test lists to reduce variability. The MBAA2 test has high test-retest reliability for percent correct and SNR50, and is suitable for the assessment of cochlear implant patients.

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A new sentence recognition test in Mandarin Chinese was developed and validated following the principles and procedures of development of the English AzBio sentence materials. The study was conducted in two stages. In the first stage, 1,020 sentences spoken by 4 talkers (2 males and 2 females) were processed through a 5-channel noise vocoder and presented to 17 normal-hearing Mandarin-speaking adults for recognition. A total of 600 sentences (150 from each talker) in the range of approximately 62 to 92% correct (mean = 78.0% correct) were subsequently selected to compile 30, 20-sentence lists. In the second stage, 30 adult CI users were recruited to verify the list equivalency. A repeated-measures analysis of variance followed by the post hoc Tukey's test revealed that 26 of the 30 lists were equivalent. Finally, a binomial distribution model was adopted to account for the inherent variability in the lists. It was found that the inter-list variability could be best accounted for with a 65-item binomial distribution model. The lower and upper limits of the 95% critical differences for one- and two-list recognition scores were then generated to provide guidance for detection of a significant difference in recognition scores in clinical settings. The final set of 26 equivalent lists contains sentence materials more difficult than those found in other speech audiometry materials in Mandarin Chinese. This test should help minimize the ceiling effects when testing sentence recognition in Mandarin-speaking CI users.

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BACKGROUND: Temporal envelope cues are conveyed by cochlear implants (CIs) to hearing loss patients to restore hearing. Although CIs could enable users to communicate in clear listening environments, noisy environments still pose a problem. To improve speech-processing strategies used in Chinese CIs, we explored the relative contributions made by the temporal envelope in various frequency regions, as relevant to Mandarin sentence recognition in noise. METHODS: Original speech material from the Mandarin version of the Hearing in Noise Test (MHINT) was mixed with speech-shaped noise (SSN), sinusoidally amplitude-modulated speech-shaped noise (SAM SSN), and sinusoidally amplitude-modulated (SAM) white noise (4 Hz) at a + 5 dB signal-to-noise ratio, respectively. Envelope information of the noise-corrupted speech material was extracted from 30 contiguous bands that were allocated to five frequency regions. The intelligibility of the noise-corrupted speech material (temporal cues from one or two regions were removed) was measured to estimate the relative weights of temporal envelope cues from the five frequency regions. RESULTS: In SSN, the mean weights of Regions 1-5 were 0.34, 0.19, 0.20, 0.16, and 0.11, respectively; in SAM SSN, the mean weights of Regions 1-5 were 0.34, 0.17, 0.24, 0.14, and 0.11, respectively; and in SAM white noise, the mean weights of Regions 1-5 were 0.46, 0.24, 0.22, 0.06, and 0.02, respectively. CONCLUSIONS: The results suggest that the temporal envelope in the low-frequency region transmits the greatest amount of information in terms of Mandarin sentence recognition for three types of noise, which differed from the perception strategy employed in clear listening environments.

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The familiar talker advantage is the finding that a listener's ability to perceive and understand a talker is facilitated when the listener is familiar with the talker. However, it is unclear when the benefits of familiarity emerge and whether they strengthen over time. To better understand the time course of the familiar talker advantage, we assessed the effects of long-term, implicit voice learning on 89 young adults' sentence recognition accuracy in the presence of four-talker babble. A university professor served as the target talker in the experiment. Half the participants were students of the professor and familiar with her voice. The professor was a stranger to the remaining participants. We manipulated the listeners' degree of familiarity with the professor over the course of a semester. We used mixed effects modeling to test for the effects of the two independent variables: talker and hours of exposure. Analyses revealed a familiar talker advantage in the listeners after 16 weeks (∼32 h) of exposure to the target voice. These results imply that talker familiarity (outside of the confines of a long-term, familial relationship) seems to be a much quicker-to-emerge, reliable cue for bootstrapping spoken language perception than previous literature suggested.

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Recently we showed that higher reward results in increased pupil dilation during listening (listening effort). Remarkably, this effect was not accompanied with improved speech reception. Still, increased listening effort may reflect more in-depth processing, potentially resulting in a better memory representation of speech. Here, we investigated this hypothesis by also testing the effect of monetary reward on recognition memory performance. Twenty-four young adults performed speech reception threshold (SRT) tests, either hard or easy, in which they repeated sentences uttered by a female talker masked by a male talker. We recorded the pupil dilation response during listening. Participants could earn a high or low reward and the four conditions were presented in a blocked fashion. After each SRT block, participants performed a visual sentence recognition task. In this task, the sentences that were presented in the preceding SRT task were visually presented in random order and intermixed with unfamiliar sentences. Participants had to indicate whether they had previously heard the sentence or not. The SRT and sentence recognition were affected by task difficulty but not by reward. Contrary to our previous results, peak pupil dilation did not reflect effects of reward. However, post-hoc time course analysis (GAMMs) revealed that in the hard SRT task, the pupil response was larger for high than low reward. We did not observe an effect of reward on visual sentence recognition. Hence, the current results provide no conclusive evidence that the effect of monetary reward on the pupil response relates to the memory encoding of speech.

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Non-native listeners deal with adverse listening conditions in their daily life much harder than native listeners. However, previous work in our laboratories found that native Chinese listeners with native English exposure may improve the use of temporal fluctuations of noise for English vowel identification. The purpose of this study was to investigate whether Chinese listeners can generalize the use of temporal cues for the English sentence recognition in noise. Institute of Electrical and Electronics Engineers (IEEE) sentence recognition in quiet condition, stationary noise, and temporally-modulated noise were measured for native American English listeners (EN), native Chinese listeners in the United States (CNU), and native Chinese listeners in China (CNC). Results showed that in general, EN listeners outperformed the two groups of CN listeners in quiet and noise, while CNU listeners had better scores of sentence recognition than CNC listeners. Moreover, the native English exposure helped CNU listeners use high-level linguistic cues more effectively and take more advantage of temporal fluctuations of noise to process English sentence in severely degraded listening conditions [i.e., the signal-to-noise ratio (SNR) of -12 dB] than CNC listeners. These results suggest a significant effect of language experience on the auditory processing of both speech and noise.

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A bio-inspired coding (BIC) strategy was implemented in this study with the goal of better representation of spectral and temporal information. The auditory nerve fibers' (ANFs) characteristics such as refractory recovery, facilitation and spatial spread were obtained from ECAP data recorded in 11 CI recipients. These characteristics, together with a non-individualized model-derived adaptation effect, were integrated into the BIC strategy for a better selection of channels. Two variations of the BIC strategy were compared to the conventional advanced combination encoder (ACE) coding strategy: the BIC-I strategy based on the individual CI recipients' ECAP parameters, and the BIC-G strategy based on the median values of ECAP parameters from all CI recipients who participated in the study. The melodic contour identification (MCI) and Oldenburg sentence recognition in noise (OLSA) tests were used to assess and compare the three coding strategies. A significantly better performance in the transformed MCI test results with the rationalized arcsine transformation, was observed for both BIC strategy variations compared to the ACE strategy. There was no significant difference between the two variations of the BIC strategy and the ACE strategy in the OLSA test. No correlation was found between recovery time constants, absolute refractory periods, left and right width of SOE functions from three test electrodes and CI recipients' performances in the two experiments. However, significant correlations were found between facilitation time constant and amplitude and the results of the MCI and OLSA tests for the two variations of the BIC strategy.

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To compare sentence recognition scores in quiet and noise in 8 to 15-years old children using bimodal hearing in CI only condition and bimodal condition (BM) (CI + HA). Twenty prelingually deafened participants (8-15 years) using cochlear implant in one ear and hearing aid in the other ear were recruited. The sentence recognition was assessed in CI Quiet, CI + 15 dB SNR, CI + 8 dB SNR, BM Quiet, BM + 15 dB SNR and BM + 8 dB SNR. The highest sentence recognition scores were obtained in the quiet condition, followed by the + 15 dB SNR and then by the + 8 dB SNR condition in both CI only and BM conditions. The sentence recognition scores obtained in BM condition were significantly better than CI only condition. Variables like unaided PTA and aided PTA correlated significantly with the sentence recognition scores in BM conditions. This study was done on Indian population where till date no published data is available. It recommends that all the school going children using unilateral cochlear implants should be recommended to use a hearing aid in the contra lateral ear. This practice will help them to receive all the binaural benefits, better listening in noise, localization, spatial release from masking and pitch perception in comparison to unilateral CI use. Moreover, it will help to keep the auditory nerve viable for future implantation which is an important implication for children who have limited benefit from the contra lateral hearing aid.

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This experiment examined the neural correlates of second language (L2) speech perception in noise in advanced Spanish students. Participants completed a speech perception task in quiet and noise in their first language (L1 = English) and L2 during fMRI. Behavioral tests of L2 Spanish sentence recognition confirmed that advanced learners of Spanish can recognize sentences in quiet and in noise with an average of 85.45% and 74.43% accuracy, respectively. While listening to degraded sentences in the L2, both auditory and executive processing regions (specifically those of attention) were activated. While listening to L2 sentences in noise, learners focused on decoding the speech signal at the perceptual level, indicating a bottom-up processing strategy relying heavily on the signal's phonetic detail. During the processing of L1 in noise there was only significant activation in executive processing regions like the cingulate cortex and a region linked to lexical-semantic access (LIFG). In this case, participants appear to use a top-down strategy for sentence recognition, relying on lexical resources using a holistic strategy for perception. These findings suggest that L2 learners use fundamentally different perceptual strategies and neural circuits for understanding speech in noise in their L1 and L2.

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In difficult listening situations, such as in noisy environments, one would expect speech intelligibility to improve over time thanks to noise adaptation and/or to speech predictability facilitating the recognition of upcoming words. We tested this possibility by presenting normal-hearing human listeners (N = 100; 70 women) with sentences and measuring word recognition as a function of word position in a sentence. Sentences were presented in quiet and in competition with various masker sounds at individualized levels where listeners had 50% probability of recognizing a full sentence. Contrary to expectations, recognition was best for the first word and gradually deteriorated with increasing word position along the sentence. The worsening in recognition was unlikely due to differences in word audibility or word type and was uncorrelated with age or working memory capacity. Using a probabilistic model of word recognition, we show that the worsening effect probably occurs because misunderstandings generate inaccurate predictions that outweigh the benefits from accurate predictions. Analyses also revealed that predictions overruled the potential benefits from noise adaptation. We conclude that although speech predictability can facilitate sentence recognition, it can also result in declines in word recognition as the sentence unfolds because of inaccuracies in prediction.

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BACKGROUND AND OBJECTIVES: Depending on the kind of task and/or material, listeners sometimes need to pay attention to understand communication. The present study aimed to estimate a listener's amount of effort needed to understand communication by using recognition score and response time as a function of signal-to-noise ratio (SNR) and to confirm his/ her task dependency for listening effort. SUBJECTS AND METHODS: Forty-eight young adults with normal hearing participated in the study. As stimuli, Korean Speech Perception in Noise test without a question tag and three consecutive digits were used for sentence recognition (or single-task) and arithmetic (or dual-task), respectively. Both tasks were measured in quiet and under four SNR (i.e., 0, -4, -8, -12 dB) conditions. Their outcomes were analyzed and compared in terms of percent correct and response time. RESULTS: Sentence recognition scores and arithmetic scores decreased as the level of noise increased. Response time for sentence recognition decreased as noise increased, whereas the response time for arithmetic increased as noise increased. In addition, there was a negative correlation between error percent and response time in the sentence recognition. Conversely, a positive correlation between error percent and response time appeared in the arithmetic test. CONCLUSIONS: Listening effort showed a different pattern based on the kind of task, single vs. dual, while the dual-task required greater effort from the listener.

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BACKGROUND AND OBJECTIVES: Depending on the kind of task and/or material, listeners sometimes need to pay attention to understand communication. The present study aimed to estimate a listener’s amount of effort needed to understand communication by using recognition score and response time as a function of signal-to-noise ratio (SNR) and to confirm his/ her task dependency for listening effort. SUBJECTS AND METHODS: Forty-eight young adults with normal hearing participated in the study. As stimuli, Korean Speech Perception in Noise test without a question tag and three consecutive digits were used for sentence recognition (or single-task) and arithmetic (or dual-task), respectively. Both tasks were measured in quiet and under four SNR (i.e., 0, -4, -8, -12 dB) conditions. Their outcomes were analyzed and compared in terms of percent correct and response time. RESULTS: Sentence recognition scores and arithmetic scores decreased as the level of noise increased. Response time for sentence recognition decreased as noise increased, whereas the response time for arithmetic increased as noise increased. In addition, there was a negative correlation between error percent and response time in the sentence recognition. Conversely, a positive correlation between error percent and response time appeared in the arithmetic test. CONCLUSIONS: Listening effort showed a different pattern based on the kind of task, single vs. dual, while the dual-task required greater effort from the listener.

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Previous work has shown that masked-sentence recognition is particularly poor when the masker is composed of two competing talkers, a finding that is attributed to informational masking. Informational masking tends to be largest when the target and masker talkers are perceptually similar. Reductions in masking have been observed for a wide range of target and masker differences, including language: Performance is better when the target and masker talkers speak in different languages, compared with the same language. The present study evaluated normal-hearing adults' sentence recognition in a two-talker masker as a function of the perceptual similarity between the target and each of the two masker streams. The target was English, and the maskers were composed of English, time-reversed English, or Dutch. These three masker types are known to vary in the informational masking they exert. The two talkers within the two-talker maskers were either congruent (e.g., both English) or incongruent (e.g., one English, one Dutch). As predicted, mean performance was worse for the congruent English masker than the congruent time-reversed English or congruent Dutch maskers. Incongruent two-talker maskers, with just one English masker stream, were only modestly less effective than the congruent English masker. This result indicates that two-talker masker effectiveness was determined predominantly by the one masker stream that was most perceptually similar to the target. Speech recognition in a single-talker masker differed only marginally between the English, Dutch, and time-reversed English masker types, suggesting that perceptual similarity may be more critical in a two-talker than a one-talker masker.

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PURPOSE: With the advent of Bluetooth technology, many of the assistive listening devices for hearing have become manufacturer specific, with little objective information about the performance provided. METHOD: Thirty native English-speaking adults (mean age 29.8) with normal hearing were tested pseudo-randomly with two major hearing aid manufacturers' proprietary Bluetooth connectivity devices paired to the accompanying manufacturer's specific hearing aids. Sentence recognition performance was objectively measured for each system with signals transmitted via a land-line to the same iPhone in two conditions. RESULTS: There was a significant effect of participant's performance according to listening condition. There was no significant effect between device manufacturers according to listening condition, but there was a significant effect in participant's perception of "quality of sound". CONCLUSIONS: Despite differences in signal transmission for each devise, when worn by participants both the systems performed equally. In fact, participants expressed personal preferences for specific technology that was largely due to their perceived quality of sound while listening to recorded signals. While further research is necessary to investigate other measures of benefit for Bluetooth connectivity devices, preliminary data suggest that in order to ensure comfort and compatibility, not only should objective measures of the patient benefit be completed, but also assessing the patient's perception of benefit is equally important. Implications for Rehabilitation All professionals who work with individuals with hearing loss, become aware of the differences in the multiple choices for assistive technology readily available for hearing loss. With the ever growing dispensing of Bluetooth connectivity devices coupled to hearing aids, there is an increased burden to determine whether performance differences could exist between manufacturers. There is a growing need to investigate other measures of benefit for Bluetooth hearing aid connectivity devices that not only include objective measures, but also patient perception of benefit.

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OBJECTIVE: While potentially improving audibility for listeners with considerable high frequency hearing loss, the effects of implementing nonlinear frequency compression (NFC) for listeners with moderate high frequency hearing loss are unclear. The purpose of this study was to investigate the effects of activating NFC for listeners who are not traditionally considered candidates for this technology. DESIGN: Participants wore study hearing aids with NFC activated for a 3-4 week trial period. After the trial period, they were tested with NFC and with conventional processing on measures of consonant discrimination threshold in quiet, consonant recognition in quiet, sentence recognition in noise, and acceptableness of sound quality of speech and music. STUDY SAMPLE: Seventeen adult listeners with symmetrical, mild to moderate sensorineural hearing loss participated. Better ear, high frequency pure-tone averages (4, 6, and 8 kHz) were 60 dB HL or better. RESULTS: Activating NFC resulted in lower (better) thresholds for discrimination of /s/, whose spectral center was 9 kHz. There were no other significant effects of NFC compared to conventional processing. CONCLUSION: These data suggest that the benefits, and detriments, of activating NFC may be limited for this population.

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OBJECTIVE: Specific computer-based auditory training may be a useful completion in the rehabilitation process for cochlear implant (CI) listeners to achieve sufficient speech intelligibility. This study evaluated the effectiveness of a computerized, phoneme-discrimination training programme. DESIGN: The study employed a pretest-post-test design; participants were randomly assigned to the training or control group. Over a period of three weeks, the training group was instructed to train in phoneme discrimination via computer, twice a week. Sentence recognition in different noise conditions (moderate to difficult) was tested pre- and post-training, and six months after the training was completed. The control group was tested and retested within one month. STUDY SAMPLE: Twenty-seven adult CI listeners who had been using cochlear implants for more than two years participated in the programme; 15 adults in the training group, 12 adults in the control group. RESULTS: Besides significant improvements for the trained phoneme-identification task, a generalized training effect was noted via significantly improved sentence recognition in moderate noise. No significant changes were noted in the difficult noise conditions. Improved performance was maintained over an extended period. CONCLUSIONS: Phoneme-discrimination training improves experienced CI listeners' speech perception in noise. Additional research is needed to optimize auditory training for individual benefit.

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Objective This experiment was to analyze the impacts of lip -reading information on hearing im-paired subjects'sentence recognition got in noisy environment in comparing with the results obtained from the listen-ing and audio -visual testing ways .Methods Fourteen moderate hearing impaired subjects with 55 .4 ± 9 .1 years old were postlingual deafness .Their sentence recognition ability were tested in noisy environments with speech and audio-visual information separately (speech intensity :30 dB SL ,SNR:5 dB) .Results Compared with the sentence recognition administered in the speech information condition 73 .79% ± 7 .95% ,the subjects sentence recognition un-der the audio -visual condition was 86 .57% ± 5 .42% ,which was significantly different (P<0 .05) .Conclusion In noisy environment ,lip-reading can improve hearing impaired patients’ sentence recognition obviously .