Development of a Mandarin Monosyllable Recognition Test

Speech Perception and Quality-of-Life Outcomes in Mandarin-Speaking Postlingual Deaf Adults With Cochlear Implant: Any Difference With the Intonation Language Users?

OBJECTIVE

To evaluate the effects of related factors on long-term speech perception and quality-of-life (QoL) outcomes in postlingual deaf Mandarin-speaking adult cochlear implant (CI) recipients and to assess any differences between tone language and other intonation language CI adult users.

STUDY DESIGN

Retrospective cases review.

SETTING

Tertiary referral center.

PATIENTS

Forty-five adult CI recipients (48 implanted ears).

MAIN OUTCOME MEASURES

Post-CI outcomes were evaluated after follow-ups of more than 24 months using speech perception tests and QoL questionnaires. We analyzed the related factors affecting CI outcomes.

RESULTS

A shorter duration of profound deafness was predictive factors for better post-CI speech perception. Earlier implantation and better performance of vowel scores were predictive of better subjective improvements in social and emotional life. Post-CI vowel scores of over 56% indicated promising improvements in QoL.

CONCLUSION

Shorter duration of deafness could have better post-CI speech perception. Post-CI vowel scores instead of monosyllable words have the more potential to predict the QoL in Mandarin-speaking adult CI recipients.

Importance of age at 2nd implantation and interimplant interval to the outcome of bilateral prelingually deafened pediatric cochlear implantation

BACKGROUND

In Taiwan, the number of cases of sequential bilateral pediatric cochlear implantation (CI) is increasing but data regarding its effectiveness and impact of the reimbursement policy are lacking. We examined the speech perception and quality of life (QOL) of bilateral prelingually deaf children who underwent sequential CI, considering the effects of age at the time of second implantation and interimplant interval.

METHODS

We enrolled 124 Mandarin-speaking participants who underwent initial cochlear implant (CI1) in 2001-2019 and a second CI (CI2) in 2015-2020. Patients were followed up for ≥2 years and were categorized into groups based on age at the time of CI2 implantation (<3.5, 3.6-7, 7.1-10, 10.1-13, and 13.1-18 years) and interimplant interval (0.5-3, 3.1-5, 5.1-7, 7.1-10, and >10 years). We evaluated speech perception, device usage rates, and QOL using subjective questionnaires (Speech, Spatial, and Qualities of Hearing and Comprehension Cochlear Implant Questionnaire).

RESULTS

Speech perception scores of CI2 were negatively correlated with ages at the time of CI1 and CI2 implantation and interimplant interval. Older age and a longer interimplant interval were associated with higher nonuse rates for CI2 and worse auditory performance and QOL. Among individuals aged >13 years with interimplant intervals >10 years, up to 44% did not use their second ear. Patients aged 7.1 to 10 years had better speech perception and higher questionnaire scores than those aged 10.1 to 13 and 13.1 to 18 years. Furthermore, patients aged 10.1 to 13 years had a lower rate of continuous CI2 usage compared to those aged 7.1 to 10 years.

CONCLUSION

Timely implantation of CI2 is essential to achieve optimal outcomes, particularly among sequentially implanted patients with long-term deafness in the second ear and no improvement with hearing aids following CI1 implantation. For CI2 implantation, an upper limit of age of 10 years and interimplant interval of 7 years are essential to prevent suboptimal outcomes. These data can provide useful information to implant recipients, their families, and medical and audiological professionals, enabling a comprehensive understanding of the benefits and potential impacts of the timing of CI2 implantation.

Can Mandarin-speaking prelingual deaf adults benefit from cochlear implant?

BACKGROUND

With advances in cochlear implant (CI) technology, prelingual deaf adults may experience improved speech perception and quality of life (QoL). It is still a challenge for Mandarin-speaking CI user with tone recognition due to CI technology focused on intonation language.

OBJECTIVES

To evaluate the long-term post-CI auditory performance and social-emotional benefits in prelingual deaf Mandarin-speaking adults and the difference between them and post-lingual deaf adults.

MATERIAL AND METHODS

Fifty-five adult implanted ears were included (forty-six postlingual deaf group; nine prelingual deaf group). Post-CI long-term outcomes were using vowels, consonants, disyllabic words, Mandarin monosyllable words, categories of audiology performance, speech intelligibility rating, subjective social-emotional questionnaires.

RESULTS

Post-CI auditory performance and speech intelligibility of prelingual deafness adults was significantly inferior to that of those with postlingual deafness. However, both groups presented improved social-emotional benefits, with no significant difference between both groups.

CONCLUSIONS

Adult CI recipients who deaf before the age of 4 can experience benefits in social-emotional life functioning, regardless of their limited auditory performance and speech intelligibility. Therefore, prelingual Mandarin-speaking deaf adults, especially those using oral communication, can be considered as relative indications for cochlear implantation.

SIGNIFICANCE

To clarify and validate the benefits among Mandarin-speaking prelingual deaf adult recipients.

Psychometrically Equivalent Fante Speech Recognition Threshold Materials by a Female Talker

PURPOSE

This study aimed to create and evaluate digitally recorded speech materials for speech recognition threshold (SRT) testing among children and adults in Fante. Fifty-one (51) familiar trisyllabic words were chosen from a list of 107 widely used trisyllabic Fante words. They were digitally captured and edited to create the same root mean square as a 1-kHz calibration tone.

METHOD

The study used a three-phase cross-sectional study method. Twenty native Fante speakers with normal hearing thresholds were selected at random for listener evaluation. For each of the words, the researchers used logistic regression to measure the slope, intercepts, and psychometric function slope at 50% and from 20% to 80%. In the study, the intensity of each word was modified digitally, so that the threshold at 50% of each word was equal to the mean pure-tone average (PTA) of the participants to increase the homogeneity of the thresholds of the selected words.

RESULTS

A final list of 25 familiar homogenous words with the same tone patterns of slopes greater than 7%/dB was finally selected and recorded for speech audiometry in Fante.

CONCLUSIONS

Psychometrically equivalent trisyllabic words in Fante were successfully developed and evaluated for SRT testing in Ghana. There is a need for the development of speech audiometry materials in other Ghanaian languages.

Shortened neural conduction time in young adults with tinnitus as revealed by chirp-evoked auditory brainstem response

Tinnitus is generally considered to be caused by neuroplastic changes in the central nervous system, triggered by a loss of input from the damaged peripheral system; however, conflicting results on auditory brainstem responses (ABRs) to clicks have been reported previously in humans with tinnitus. This study aimed to compare the effect of tinnitus on ABRs to chirps with those to clicks in normal-hearing young adults with tinnitus. The results showed that the tinnitus group had no significantly poorer hearing thresholds (0.25-16 kHz), click-evoked otoacoustic emissions (1-16 kHz), and speech perception in noise (SPIN) than the control group. Although chirps evoked significantly larger wave I and V amplitudes than clicks, people with tinnitus had no significantly smaller wave I amplitudes for either stimulus. Nevertheless, adults with tinnitus exhibited significantly smaller interpeak interval (IPI) between waves I and V for chirps (IPI-chirp) but not for clicks. In addition, the IPI-chirp correlated significantly with the SPIN for individuals with tinnitus when the signal-to-noise ratio was low. The present results suggest that the chirp-evoked ABR may be a valuable clinical tool for objectively assessing the SPIN in individuals with tinnitus. Further studies should be conducted to investigate possible etiologies of tinnitus.

Long-term auditory performance and psychosocial benefits of cochlear implantation in Mandarin-speaking older adults

PURPOSE

Although previous studies have shown the efficacy of cochlear implants (CIs) in older adults, no study written in English has focused on Mandarin-speaking older recipients. Mandarin is a tonal language, it is hard to lip-read and tone recognition for CI users. This study aimed to evaluate the long-term post-CI outcomes in Mandarin-speaking older adults and the difference between them and younger recipients.

MATERIALS AND METHODS

Forty-six post-lingually deafened adults were included. Speech perception tests (vowel, consonant, disyllable words, Mandarin monosyllable recognition test, and categories of audiology performance were evaluated) and psychosocial scale were evaluated.

RESULTS

There were no significant differences between older and younger recipients in post-CI open-set speech perception. However, older recipients had significantly lower social and total scores in the subjective questionnaire than younger recipients. In both duration of deafness less than seven years and hearing years in life over 92.6 %, older recipients had no less capable speech perception than in younger.

CONCLUSION

Mandarin-speaking older recipients can improve not only speech perception but also psychosocial benefits. Well hearing experience may confer an advantage to older recipients, despite their older implanted age. These results can help provide pre-CI consultation guidelines for older Mandarin-speaking recipients.

Efficacy of hearing aid treatment on sound perception and residual hearing preservation in patients with tinnitus and coexisting hearing loss: study protocol for a randomized controlled trial

BACKGROUND

Chronic subjective tinnitus poses significant challenges in clinical practice, and it is usually associated with hearing impairment, particularly with high-frequency sensorineural hearing loss (SNHL). Patients suffering from tinnitus with SNHL experience one of the most severe sensory disabilities, and this has devastating effects on their quality of life. Nowadays, mild to moderate SNHL can be managed with a properly fitted hearing aid (HA) that provides sound amplification, and several studies suggest that HAs may also benefit those with tinnitus. However, inadequate attention has been paid by medical personnel to the impact of HA use in residual hearing protection for patients with tinnitus and coexisting SNHL, and existing evidence is still at a preliminary stage. This study aims to identify and evaluate the efficacy of the use of HAs in both sound perception and residual hearing preservation among patients with tinnitus and coexisting SNHL.

METHODS AND DESIGN

The present study is a prospective, single-center, outcome assessor and data analyst-blinded, randomized, controlled trial. Eligible participants will be recruited and randomly allocated into the HA intervention group and the waiting list control group at a ratio of 1:1. The primary outcome is to evaluate the severity of tinnitus using the Tinnitus Handicap Inventory as a continuous variable at 6 months from randomization. Secondary outcome measures include changes in hearing status and mental states. The trial will last 6 months, with follow-up visits at 3 months and 6 months.

DISCUSSION

This will be the first randomized, controlled trial to identify and evaluate HAs' efficacy on residual hearing preservation among tinnitus patients with coexisting high-frequency SNHL in China. We are aiming for novelty and generalizability, and strengths of this study are that it will examine the effectiveness of HA in patients with tinnitus and hearing impairment and will further explore the residual hearing protection provided by HA treatment in the tinnitus group.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05343026. Registered on April 25, 2022.

Dysarthric Speech Enhancement Based on Convolution Neural Network

Generally, those patients with dysarthria utter a distorted sound and the restrained intelligibility of a speech for both human and machine. To enhance the intelligibility of dysarthric speech, we applied a deep learning-based speech enhancement (SE) system in this task. Conventional SE approaches are used for shrinking noise components from the noise-corrupted input, and thus improve the sound quality and intelligibility simultaneously. In this study, we are focusing on reconstructing the severely distorted signal from the dysarthric speech for improving intelligibility. The proposed SE system prepares a convolutional neural network (CNN) model in the training phase, which is then used to process the dysarthric speech in the testing phase. During training, paired dysarthric-normal speech utterances are required. We adopt a dynamic time warping technique to align the dysarthric-normal utter-ances. The gained training data are used to train a CNN - based SE model. The proposed SE system is evaluated on the Google automatic speech recognition (ASR) system and a subjective listening test. The results showed that the proposed method could notably enhance the recognition performance for more than 10% in each of ASR and human recognitions from the unprocessed dysarthric speech. Clinical Relevance- This study enhances the intelligibility and ASR accuracy from a dysarthria speech to more than 10.

Development of the Mandarin Nonsense Word Identification Test

OBJECTIVE

This study aimed to develop a digitised Mandarin Nonsense Word Speech Perception Test for use in Malaysia, a multilingual country in Southeast Asia.

DESIGN

In Phase I, 400 vowel-consonant-vowel (VCV) nonsense word samples containing 20 Mandarin consonants in /a/, /i/, or /u/ contexts were recorded from two speakers of different genders. Acoustic analyses, sound quality ratings, and item validations were used to guide selection of items to form two gender-specific test lists. In Phase II, performance-intensity functions and test-retest reliability for the lists were established.

STUDY SAMPLE

Native Mandarin-speaking adults with normal hearing participated in Phase I (n = 10) and Phase II (n = 69).

RESULTS

Eighty-four of the 400 VCV words were selected to form two gender-specific test lists. A two-way repeated measure ANOVA revealed a significant interaction effect between speaker-gender and presentation level [F (4.88, 283.20) = 22.79, p < 0.001, η_p²= 0.28]. Intraclass correlation scores of 0.75 and 0.87 were obtained for the female-speaker and male-speaker lists respectively.

CONCLUSIONS

The preliminary normative data of the Mandarin nonsense word test have been developed. It is recommended to use separate gender-specific norms when conducting the test. The test has good validity and reliability for testing Mandarin-speaking adults in Malaysia.

A review of Mandarin speech recognition test materials for use in Singapore

OBJECTIVE

This study aimed to evaluate word lists of current Mandarin speech recognition test materials on their adaptability for use on adult Singapore Mandarin speakers.

DESIGN

This scoping review involved literature search through electronic databases for studies published in English or Mandarin, detailing the development or validation of Mandarin speech recognition test materials meant to be used in quiet. Word lists of materials were evaluated for phonemic balance (Stage 1) and familiarity to Singapore Mandarin speakers by comparing the test items against a list of 1,000 common Singapore Mandarin words (Stage 2).

STUDY SAMPLE

Thirty articles that fulfilled the inclusion and exclusion criteria were reviewed.

RESULTS

Nine sets of materials were found and evaluated in Stage 1. Among these, two sets of materials did not contain phonemically balanced word lists. The remaining seven sets of materials were evaluated in Stage 2. The percentage of unfamiliar characters to Singapore Mandarin speakers was found to be between 15% and 41% across the word lists.

CONCLUSION

None of the currently available materials contain word lists that can be readily adapted for re-recording with the voice of a Singapore Mandarin speaker. There is a need to develop original Singapore Mandarin speech recognition test materials.

Extended bandwidth nonlinear frequency compression in Mandarin-speaking hearing-aid users

BACKGROUND/PURPOSE

The high frequency information of consonant messages is important for recognition of speech. Recently, the nonlinear frequency compression (NLFC) technique has been shown to improve the speech perception in patients with high frequency hearing loss. In Mandarin, seven consonants are located over 10-16 kHz. Extended-bandwidth (EB) NLFC may provide an additional benefit for recognition of Mandarin words. The purpose of this study was to explore the effects of NLFC and EB-NLFC on Mandarin word recognition in patients with high frequency hearing loss.

METHODS

Fourteen native Mandarin-speaking adult patients, aged 20-65 years with bilateral, moderate to severe, sensorineural hearing loss, specifically high frequency hearing loss were included in single-blind randomized study. The assessment tools included the Mandarin Monosyllable Recognition Test (MMRT), Mandarin Hearing in Noise Test (MHINT), and International Outcome Inventory for Hearing Aids (IOI-HA) and sound quality scale of the hearing aids. The patients were tested under unaided condition, after which they were randomly assigned to wear NLFC and EB-NLFC hearing aids, alternatively, in a crossover fashion. After each 4-week block, the patients were tested again to obtain the test outcomes.

RESULTS

Patients with hearing aids with EB-NLFC had a significantly better word and consonant recognition using the MMRT (p<0.05). The MHINT was better for the EB-NLFC group without significant differences. The EB-NLFC group had better scores in both the IOI-HA and sound quality scale but not statistically significant.

CONCLUSION

Patients with high-frequency hearing loss may benefit more from using EB-NLFC for word and consonant recognition; however, the improvement was small under a noisy listening environment. The subjective questionnaires did not show significant benefit of EB-NLFC either.

Validation of list equivalency for Mandarin speech materials to use with cochlear implant listeners

OBJECTIVES

Speech materials validated with normal-hearing listeners may not be appropriate for clinical assessment of cochlear implant (CI) users. The aim of this study was to validate list equivalency of the Mandarin Speech Perception (MSP) sentences, disyllables, and monosyllables in Mandarin-speaking CI patients.

DESIGN

Recognition of MSP sentences, disyllables, and monosyllables each were measured for all 10 lists.

STUDY SAMPLE

67 adult and 32 pediatric Mandarin-speaking CI users.

RESULTS

There was no significant difference between adult and pediatric subject groups for all test materials. Significant differences were observed among lists within each test. After removing one or two lists within each test, no significant differences were observed among the remaining lists. While there was equal variance among lists within a given test, the variance was larger for children than for adults, and increased from monosyllables to disyllables to sentences.

CONCLUSIONS

Some adjustment to test lists previously validated with CI simulations was needed to create perceptually equivalent lists for real CI users, suggesting that test materials should be validated in the targeted population. Differences in mean scores and variance across test materials suggest that CI users may differ in their ability to make use of contextual cues available in sentences and disyllables.

The binaural masking-level difference of mandarin tone detection and the binaural intelligibility-level difference of mandarin tone recognition in the presence of speech-spectrum noise

Binaural hearing involves using information relating to the differences between the signals that arrive at the two ears, and it can make it easier to detect and recognize signals in a noisy environment. This phenomenon of binaural hearing is quantified in laboratory studies as the binaural masking-level difference (BMLD). Mandarin is one of the most commonly used languages, but there are no publication values of BMLD or BILD based on Mandarin tones. Therefore, this study investigated the BMLD and BILD of Mandarin tones. The BMLDs of Mandarin tone detection were measured based on the detection threshold differences for the four tones of the voiced vowels /i/ (i.e., /i1/, /i2/, /i3/, and /i4/) and /u/ (i.e., /u1/, /u2/, /u3/, and /u4/) in the presence of speech-spectrum noise when presented interaurally in phase (S₀N₀) and interaurally in antiphase (S_πN₀). The BILDs of Mandarin tone recognition in speech-spectrum noise were determined as the differences in the target-to-masker ratio (TMR) required for 50% correct tone recognitions between the S₀N₀ and S_πN₀ conditions. The detection thresholds for the four tones of /i/ and /u/ differed significantly (p<0.001) between the S₀N₀ and S_πN₀ conditions. The average detection thresholds of Mandarin tones were all lower in the S_πN₀ condition than in the S₀N₀ condition, and the BMLDs ranged from 7.3 to 11.5 dB. The TMR for 50% correct Mandarin tone recognitions differed significantly (p<0.001) between the S₀N₀ and S_πN₀ conditions, at –13.4 and –18.0 dB, respectively, with a mean BILD of 4.6 dB. The study showed that the thresholds of Mandarin tone detection and recognition in the presence of speech-spectrum noise are improved when phase inversion is applied to the target speech. The average BILDs of Mandarin tones are smaller than the average BMLDs of Mandarin tones.

Mandarin lexical tones identification among children with cochlear implants or hearing aids

OBJECTIVES

Mandarin Chinese is a lexical tone language that has four tones, with a change in tone denoting a change in lexical meaning. There are few studies regarding lexical tone identification abilities in deafened children using either cochlear implants (CIs) or hearing aids (HAs). Furthermore, no study has compared the lexical tone identification abilities of deafened children with their hearing devices turned on and off. The present study aimed to investigate the lexical tone identification abilities of deafened children with CIs or HAs.

METHODS

Forty prelingually deafened children (20 with CIs and 20 with HAs) participated in the study. In the HA group, 20 children were binaurally aided. In the CI group, all of the children were unilaterally implanted. All of the subjects completed a computerized lexical tone pairs test with their hearing devices turned on and off. The correct answers of all items were recorded as the total score and the correct answers of the tone pairs were recorded as subtotal scores.

RESULTS

No significant differences in the tone pair identification scores were found between the CI group and HA group either with the devices turned on or off (t=1.62, p=0.11; t=1.863, p=0.07, respectively). The scores in the aided condition were higher than in the unaided condition regardless of the device used (t=22.09, p<0.001, in the HA group; t=20.20, p<0.001, in the CI group). Significantly higher scores were found in the tone pairs that contained tone 4. Age at fitting of the devices was correlated with tone identification abilities in both the CI and HA groups. Other demographic factors were not correlated with tone identification ability.

CONCLUSIONS

The hearing device, whether a hearing aid or cochlear implant, is beneficial for tone identification. The lexical tone identification abilities were similar regardless of whether the subjects wore a HA or CI. Lexical tone pairs with different durations and dissimilar tone contour patterns are more easily identified. Receiving devices at earlier age tends to produce better lexical tone identification abilities in prelingually deafened children.

Audiovisual speech perception at various presentation levels in Mandarin-speaking adults with cochlear implants

Objectives

(1) To evaluate the recognition of words, phonemes and lexical tones in audiovisual (AV) and auditory-only (AO) modes in Mandarin-speaking adults with cochlear implants (CIs); (2) to understand the effect of presentation levels on AV speech perception; (3) to learn the effect of hearing experience on AV speech perception.

Methods

Thirteen deaf adults (age = 29.1±13.5 years; 8 male, 5 female) who had used CIs for >6 months and 10 normal-hearing (NH) adults participated in this study. Seven of them were prelingually deaf, and 6 postlingually deaf. The Mandarin Monosyllablic Word Recognition Test was used to assess recognition of words, phonemes and lexical tones in AV and AO conditions at 3 presentation levels: speech detection threshold (SDT), speech recognition threshold (SRT) and 10 dB SL (re:SRT).

Results

The prelingual group had better phoneme recognition in the AV mode than in the AO mode at SDT and SRT (both p = 0.016), and so did the NH group at SDT (p = 0.004). Mode difference was not noted in the postlingual group. None of the groups had significantly different tone recognition in the 2 modes. The prelingual and postlingual groups had significantly better phoneme and tone recognition than the NH one at SDT in the AO mode (p = 0.016 and p = 0.002 for phonemes; p = 0.001 and p<0.001 for tones) but were outperformed by the NH group at 10 dB SL (re:SRT) in both modes (both p<0.001 for phonemes; p<0.001 and p = 0.002 for tones). The recognition scores had a significant correlation with group with age and sex controlled (p<0.001).

Conclusions

Visual input may help prelingually deaf implantees to recognize phonemes but may not augment Mandarin tone recognition. The effect of presentation level seems minimal on CI users' AV perception. This indicates special considerations in developing audiological assessment protocols and rehabilitation strategies for implantees who speak tonal languages.

Development and preliminary verification of a Mandarin-based hearing-aid fitting strategy

Objective

The purpose of this study was to design and to verify a new hearing-aid fitting strategy (Aescu HRL-1) based on the acoustic features of Mandarin. The subjective and objective outcomes were compared to those fitted with NAL-NL1 (National Acoustic Laboratory Non-Linear, version1) in Mandarin-speaking hearing-aid users.

Design

Fifteen subjects with sensorineural hearing loss participated in this preliminary study. Each subject wore a pair of four-channel hearing aids fitted with the Aescu HRL-1 and NAL-NL1 prescriptions alternatively for 1 month. Objective and subjective tests including the Mandarin Monosyllable Recognition Test (MMRT), Mandarin Hearing in Noise Test (MHINT), International Outcome Inventory for Hearing Aids (IOI-HA), and a sound-quality questionnaire were used to evaluate the performance of the two prescriptions.

Results

The mean MMRT scores were 79.9% and 81.1% for NAL-NL1 and Aescu HRL-1 respectively. They are not statistically different. The corresponding MHINT signal-to-noise ratios were 0.87 and 0.85 dB, also, no significant difference was found between these two strategies. However, in subjective questionnaires, overall, the sound-quality and IOI-HA scores were higher for Aescu HRL-1.

Conclusions

The speech recognition performance based on Aescu HRL-1 is as good as that of NAL-NL1 for Mandarin-speaking hearing-aid users. Moreover, the subjects generally responded that Aescu HRL-1 provides a more natural, richer, and better sound quality than does NAL-NL1.

Performance-Intensity Functions of Mandarin Word Recognition Tests in Noise: Test Dialect and Listener Language Effects

Purpose

This study established the performance-intensity function for Beijing and Taiwan Mandarin bisyllabic word recognition tests in noise in native speakers of Wu Chinese. Effects of the test dialect and listeners' first language on psychometric variables (i.e., slope and 50%-correct threshold) were analyzed.

Method

Thirty-two normal-hearing Wu-speaking adults who used Mandarin since early childhood were compared to 16 native Mandarin-speaking adults. Both Beijing and Taiwan bisyllabic word recognition tests were presented at 8 signal-to-noise ratios (SNRs) in 4-dB steps (−12 dB to +16 dB). At each SNR, a half list (25 words) was presented in speech-spectrum noise to listeners' right ear. The order of the test, SNR, and half list was randomized across listeners. Listeners responded orally and in writing.

Results

Overall, the Wu-speaking listeners performed comparably to the Mandarin-speaking listeners on both tests. Compared to the Taiwan test, the Beijing test yielded a significantly lower threshold for both the Mandarin- and Wu-speaking listeners, as well as a significantly steeper slope for the Wu-speaking listeners.

Conclusion

Both Mandarin tests can be used to evaluate Wu-speaking listeners. Of the 2, the Taiwan Mandarin test results in more comparable functions across listener groups. Differences in the performance-intensity function between listener groups and between tests indicate a first language and dialectal effect, respectively.

Development and validation of the Mandarin disyllable recognition test

CONCLUSION

Given the phonetic balancing across lists and the validation with spectrally degraded speech, the present Mandarin disyllable recognition test (DRT) materials may be useful for assessing speech performance of Mandarin-speaking cochlear implant (CI) users. If combined with the previously developed sentence materials, these materials would help to establish standardized speech perception tests for Mandarin-speaking hearing-impaired (HI) and CI patients.

OBJECTIVES

To develop standardized Mandarin DRT materials that can be used to evaluate the speech performance of Mandarin-speaking HI and CI patients, and to establish standardized Mandarin speech perception test materials that include both disyllables and sentences.

METHODS

Ten phonetically balanced Mandarin DRT lists were developed. The DRT materials were validated in 8 normal-hearing (NH) subjects listening to unprocessed speech and in 10 NH subjects listening to a 4-channel, sine-wave vocoded acoustic simulation of CI speech processing. Performance with the DRT materials was compared to that with Mandarin sentence materials previously developed by our group.

RESULTS

The distribution of vowels, consonants, and tones within each DRT list was similar to that observed across commonly used Chinese characters. There was no significant difference in disyllable word recognition across lists in both unprocessed and four-channel vocoded speech. There was a significant correlation between disyllable and sentence recognition performance.

Development of a mandarin monosyllable test material with homogenous items (II): lists equivalence evaluation

CONCLUSIONS

A set of Chinese Mandarin monosyllable test lists with good reliability and sensitivity was established.

OBJECTIVES

The primary purpose of this study was to evaluate the equivalence of a group of monosyllable lists.

METHODS

A genetic algorithm was adopted to reorganize the material based on the Phoneme Allocation Table; 10 lists with 25 monosyllabic test items in each were generated. A two-factor design was used for the equivalence evaluation test. A total of 80 normal-hearing and native Mandarin-speaking university students (40 males and 40 females) participated in the trial. Every subject was tested with all 10 lists in sequence at 5 presentation levels (-5, 0, 5, 10, and 15 dB HL). Performance-intensity (P-I) function of each list was fit before P-I curve slope and recognition threshold were calculated.

RESULTS

Equivalence evaluation results indicated good psychophysical equivalence between the 10 lists except for list 2. List 9 has a reused item. After the elimination of lists 2 and 9, multivariate ANOVA revealed a good equivalence between the remaining eight lists (p = 0.136). The mean threshold of eight equivalent lists was 10.32 ± 0.38 dB HL, while the mean slope was 5.00 ± 0.29%/dB.

Mandarin Chinese speech recognition by pediatric cochlear implant users

OBJECTIVES

Because of difficulties associated with pediatric speech testing, most pediatric cochlear implant (CI) speech studies necessarily involve basic and simple perceptual tasks. There are relatively few studies regarding Mandarin-speaking pediatric CI users' perception of more difficult speech materials (e.g., words and sentences produced by multiple talkers). Difficult speech materials and tests necessarily require older pediatric CI users, who may have different etiologies of hearing loss, duration of deafness, CI experience. The present study investigated how pediatric CI patient demographics influence speech recognition performance with relatively difficult test materials and methods.

METHODS

In this study, open-set recognition of multi-talker (two males and two females) Mandarin Chinese disyllables and sentences were measured in 37 Mandarin-speaking pediatric CI users. Subjects were grouped according to etiology of deafness and previous acoustic hearing experience. Group 1 subjects were all congenitally deafened with little-to-no acoustic hearing experience. Group 2 subjects were not congenitally deafened and had substantial acoustic hearing experience prior to implantation. Multiple linear regression analyses were performed within each group using subject demographics such as age at implantation and age at testing.

RESULTS

Pediatric CI performance was generally quite good. For Group 1, mean performance was 82.3% correct for disyllables and 82.8% correct for sentences. For Group 2, mean performance was 76.6% correct for disyllables and 84.4% correct for sentences. For Group 1, multiple linear regression analyses showed that age at implantation predicted disyllable recognition, and that age at implantation and age at testing predicted sentence recognition. For Group 2, neither age at implantation nor age at testing predicted disyllable or sentence recognition. Performance was significantly better with the female than with the male talkers.

CONCLUSIONS

Consistent with previous studies' findings, early implantation provided a significant advantage for profoundly deaf children. Performance for both groups was generally quite good for the relatively difficult materials and tasks, suggesting that open-set word and sentence recognition may be useful in evaluating speech performance with older pediatric CI users. Differences in disyllable recognition between Groups 1 and 2 may reflect differences in adaptation to electric stimulation. The Group 1 subjects developed speech patterns exclusively via electric stimulation, while the Group 2 subjects adapted to electric stimulation relative to previous acoustic patterns.

Development and validation of the Mandarin speech perception test

Currently there are few standardized speech testing materials for Mandarin-speaking cochlear implant (CI) listeners. In this study, Mandarin speech perception (MSP) sentence test materials were developed and validated in normal-hearing subjects listening to acoustic simulations of CI processing. Percent distribution of vowels, consonants, and tones within each MSP sentence list was similar to that observed across commonly used Chinese characters. There was no significant difference in sentence recognition across sentence lists. Given the phonetic balancing within lists and the validation with spectrally degraded speech, the present MSP test materials may be useful for assessing speech performance of Mandarin-speaking CI listeners.