Psychometrically equivalent mandarin bisyllabic speech discrimination materials spoken by male and female talkers

Chinese Emotional Speech Audiometry Project (CESAP): Establishment and Validation of a New Material Set With Emotionally Neutral Disyllabic Words

PURPOSE

The Chinese Emotional Speech Audiometry Project (CESAP) aims to establish a new material set for Chinese speech audiometry tests, which can be used in both neutral and emotional prosody settings. As the first endeavor of CESAP, this study demonstrates the development of the material foundation and reports its validation in neutral prosody.

METHOD

In the development step, 40 phonetically balanced word lists consisting of 30 Chinese disyllabic words with neutral valence were first generated. In a following affective rating experiment, 35 word lists were qualified for validation based on the familiarity and valence ratings from 30 normal-hearing (NH) participants. For validation, performance-intensity functions of each word list were fitted with responses from 60 NH subjects under six presentation levels (-1, 3, 5, 7, 11, and 20 dB HL). The final material set was determined by the intelligibility scores at each decibel level and the mean slopes.

RESULTS

First, 35 lists satisfied the criteria of phonetic balance, limited repetitions, high familiarity, and neutral valence and were selected for validation. Second, 15 lists were compiled in the final material set based on the pairwise differences in intelligibility scores and the fitted 20%-80% slopes. The established material set had high reliability and validity and was sensitive to detect intelligibility changes (50% slope: 6.20%/dB; 20%-80% slope: 5.45%/dB), with small covariance of variation for thresholds (15%), 50% slope (12%), and 20%-80% slope (12%).

CONCLUSION

Our final material set of 15 word lists takes the initiative to control the emotional aspect of audiometry tests, which enriches available Mandarin speech recognition materials and warrants future assessments in emotional prosody among populations with hearing impairments.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.25742814.

List Equivalency and Critical Differences of a Mandarin Bamford-Kowal-Bench Sentence in Babble Noise Test for Adults and Preschool Children With Normal Hearing

PURPOSE

The purpose of this study was to determine the speech recognition equivalence of Mandarin Bamford-Kowal-Bench (BKB) sentence lists with adults and children with normal hearing.

METHOD

A total of 32 lists, each of nine sentences, were compiled from a corpus of BKB-like sentences with paired babble in Mandarin. Interlist equivalence, critical differences, and sensitivity of performance to signal-to-noise ratio (SNR) were examined. Experiment 1 included 64 native Mandarin-speaking adults with normal hearing. Experiment 2 included 54 native Mandarin-speaking children with normal hearing aged 4-6 years.

RESULTS

Among the 32 sentence lists, 28 lists were confirmed to be equivalent in adults, with a mean SNR required for 50% correct (SNR50) of -5.9 ± 0.1 dB, a mean slope of 22.3%/dB ± 1.5%/dB, and a grand 95% critical difference subsequently calculated as 27.2% for score. From the 28 equivalent lists, 27 lists were selected and observed to be equivalent in children, with a mean SNR50 threshold of -2.0 ± 0.2 dB, a mean slope of 15.8%/dB ± 1.1%/dB, and a grand 95% critical difference of 24.6% for score.

CONCLUSIONS

The Mandarin BKB sentences in babble noise test offers an opportunity for clinicians and researchers to assess speech understanding in adults and preschool children in an efficient manner. For comparisons of performance in different test conditions, 28 equivalent lists are available for adults and 27 equivalent lists for preschool children. The 95% critical difference values can be used for total percentage correct or SNR for 50% performance. Future work will examine the clinical utility for school-age children and children who are deaf and hard of hearing.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.24400066.

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.

Validating Four Hmong Word Recognition Tests With Normal-Hearing Bilingual Hmong Individuals

Purpose:

The purpose of this study was to validate four digitally recorded and phonetically balanced 50-word recognition lists in the White Hmong dialect with normal-hearing bilingual Hmong adults.

Method:

Using a randomized, incomplete-block design, each participant listened to and repeated four unique Hmong lists delivered by a female and a male talker. Participants were also tested with an English word list—List 1A of the Northwestern University Auditory Test No. 6. Participants' correct pronunciation of each word was scored. A nonparametric Mann–Whitney U Location Difference Test for Equivalence using two one-sided tests equivalence hypothesis: −0.02 < [(List_1) – (List_2)] < 0.02 was conducted to assess equivalence among all four Hmong and the English lists.

Results:

Seventy Hmong speakers participated in this study (35 women, 35 men; M age = 29.5 years, SD = 7.1). In all four Hmong lists, 93.5% (187/200) words met the validation criteria for ≥ 92% correct pronunciation. The 13 difficult words were deemed adequate by a Hmong panel and, therefore, were included to maintain four unique, balanced word lists. The test revealed that the Hmong and English word lists were considered equivalent at the 2% bound.

Conclusion:

The four Hmong word lists were validated to ensure an equal range of word difficulty across the lists.

Relative Weights of Temporal Envelope Cues in Different Frequency Regions for Mandarin Vowel, Consonant, and Lexical Tone Recognition

Objectives: Mandarin-speaking users of cochlear implants (CI) perform poorer than their English counterpart. This may be because present CI speech coding schemes are largely based on English. This study aims to evaluate the relative contributions of temporal envelope (E) cues to Mandarin phoneme (including vowel, and consonant) and lexical tone recognition to provide information for speech coding schemes specific to Mandarin.

Design: Eleven normal hearing subjects were studied using acoustic temporal E cues that were extracted from 30 continuous frequency bands between 80 and 7,562 Hz using the Hilbert transform and divided into five frequency regions. Percent-correct recognition scores were obtained with acoustic E cues presented in three, four, and five frequency regions and their relative weights calculated using the least-square approach.

Results: For stimuli with three, four, and five frequency regions, percent-correct scores for vowel recognition using E cues were 50.43–84.82%, 76.27–95.24%, and 96.58%, respectively; for consonant recognition 35.49–63.77%, 67.75–78.87%, and 87.87%; for lexical tone recognition 60.80–97.15%, 73.16–96.87%, and 96.73%. For frequency region 1 to frequency region 5, the mean weights in vowel recognition were 0.17, 0.31, 0.22, 0.18, and 0.12, respectively; in consonant recognition 0.10, 0.16, 0.18, 0.23, and 0.33; in lexical tone recognition 0.38, 0.18, 0.14, 0.16, and 0.14.

Conclusion: Regions that contributed most for vowel recognition was Region 2 (502–1,022 Hz) that contains first formant (F1) information; Region 5 (3,856–7,562 Hz) contributed most to consonant recognition; Region 1 (80–502 Hz) that contains fundamental frequency (F0) information contributed most to lexical tone recognition.

Development Of Speech Material For An Armenian Speech Recognition Threshold Test

Introduction — For the Armenian language, no standardized audiometric speech perception test is available. The purpose of this research was to develop, digitally record and evaluate an Armenian multisyllabic speech audiometry test, which can be used to measure speech recognition thresholds in Armenian native speakers. Material and Methods — To create a homogeneous multisyllabic speech corpus, Armenian numerals from 10-100 with 2-4 syllables were selected as general sample and digitally recorded by a female native Armenian speaker. For equalizing the speech recognition threshold between the test items, the speech discrimination function for each numeral was subsequently evaluated by five normal hearing native Armenian listeners in an experimental study. Results — Based on the phonemic structure of the Armenian language, 20 phonemically homogeneous test lists were created. The phoneme distributions of each test list correlated significantly and positively with that of the general sample (all Pearson moment correlation coefficients >0.960; all ps <0.001). Comparison of the phoneme distributions of test lists to that of the Armenian language showed that the test lists represent the language corpus quite well. After adjusting for actual threshold levels, speech discrimination functions are comparable between all numerals used. Conclusion — The developed test lists are a phonetically homogenous representation of the Armenian language and serve as an appropriated base for future clinical measurements of speech recognition threshold in Armenian speaking listeners.

Development of SC-10: A psychometrically equivalent Singapore Mandarin disyllabic word list for clinical speech audiometry use

Objective

The aim of this study is to develop and evaluate a set of psychometrically equivalent disyllabic wordlist (SC-10) in Singapore Mandarin for clinical use.

Study design

A preliminary set of 1000 words were obtained from a dictionary of frequently used words by Singapore students. Ten native judges rate the familiarity level of each word. This is followed by a face-to-face public survey to rank the shortlisted word set from most to least familiar. The final 108 disyllabic words were recorded by a native female talker. 20 normal hearing subjects were used to obtain the percentage of correct word recognition at 24 intensity levels (−10 dB HL to 26 dB HL in 2 dB increment). Psychometric function slopes were calculated for each word. 100 words were eventually chosen and assigned into ten 10-word lists based on a psychometric balancing protocol. Minor digital adjustments were made to the intensity of each wordlist to improve their auditory homogeneity.

The developed SC-10 wordlists were validated by a separate group of 25 normal hearing subjects. Test-retest reliability was carried out on 20 out of 25 participants at the selected intensity levels (SRT-5, SRT, SRT+5).

Results

The calculated regression slopes in the psychometric functions for the ten lists are between 8.0 and 9.8%/dB. Single factor ANOVA analysis showed no significant difference in both the mean intensity required to obtain 50% recognition score (f = 0.109, df = 9, p = 0.999) and the slopes of the psychometric functions (f = 0.078, df = 9, p = 0.999) between the ten word lists. List validation on 25 normal hearing participants (PTA = 11.0 dB HL, SD = 4.3) showed a mean speech recognition threshold (SRT) of 9.3 dB HL (SD = 3.5)and regression slope of 8.395%/dB. Quadratic regression analysis showed a positive correlation (r² = 0.923) between presentation level and word recognition score (WRS). The difference between PTA and SRT of each subject all fall within the clinically acceptable difference of 10 dB HL. Test-retest reliability, carried out on 20 subjects at three levels (SRT-5, SRT, and SRT+5 dB), showed no significance difference between word recognition score when the same participant is tested again at the same intensity level using a different wordlist.

Conclusion

All in all, it shows that the SC-10 speech materials are valid for clinical use for Mandarin speech audiometry in Singapore.

The Relative Weight of Temporal Envelope Cues in Different Frequency Regions for Mandarin Disyllabic Word Recognition

Objectives

Acoustic temporal envelope (E) cues containing speech information are distributed across all frequency spectra. To provide a theoretical basis for the signal coding of hearing devices, we examined the relative weight of E cues in different frequency regions for Mandarin disyllabic word recognition in quiet.

Design

E cues were extracted from 30 continuous frequency bands within the range of 80 to 7,562 Hz using Hilbert decomposition and assigned to five frequency regions from low to high. Disyllabic word recognition of 20 normal-hearing participants were obtained using the E cues available in two, three, or four frequency regions. The relative weights of the five frequency regions were calculated using least-squares approach.

Results

Participants correctly identified 3.13-38.13%, 27.50-83.13%, or 75.00-93.13% of words when presented with two, three, or four frequency regions, respectively. Increasing the number of frequency region combinations improved recognition scores and decreased the magnitude of the differences in scores between combinations. This suggested a synergistic effect among E cues from different frequency regions. The mean weights of E cues of frequency regions 1-5 were 0.31, 0.19, 0.26, 0.22, and 0.02, respectively.

Conclusion

For Mandarin disyllabic words, E cues of frequency regions 1 (80-502 Hz) and 3 (1,022-1,913 Hz) contributed more to word recognition than other regions, while frequency region 5 (3,856-7,562) contributed little.

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.

Development of Mandarin speech test materials for civilian pilots in China

Supplemental Digital Content is available in the text

The MAndarin spoken word-Picture IDentification test in noise-Adaptive (MAPID-A) measures subtle speech-recognition-in-noise changes and spatial release from masking in very young children

Background

Spatial release of masking (SRM) is a measure of an individual’s ability to perform speech-noise segregation, which is usually quantified by the extent of improvement of the individual’s speech recognition performance when the noise is switched from a spatially co-located position (e.g., speech and noise both presented from the front) to a spatially separated position (e.g., speech presented from the front and noise presented from the right side) with reference to the target speech. SRM is a combined measure of head shadow and binaural unmasking benefits. SRM has only been investigated in young children at group level but not at individual participant level in the international literature due to the lack of reliable speech recognition test materials able to detect subtle statistically significant within-participant changes in speech-recognition-in-noise thresholds.

Method

The performance to signal-to-noise ratio (P-SNR) functions of twenty-four disyllabic words were obtained from 40 native Mandarin-speaking children aged 3.6–6.2 years with reported normal speech, language and hearing. The test items’ difficulty levels were homogenized by adjusting the speech intensity level of each item so that the adjusted signal-to-noise ratio for 50% correct score (SNR-50%) point of each item would overlap at the mean SNR-50% point of all test items. In the MAPID-A, the homogenized test items were randomly presented in an adaptive testing procedure at a fixed noise intensity level, but the speech intensity level of the upcoming test item varied in 2-dB SNR steps depending on the recognition result of the previous test item. The SNR reversal point is marked by a change from a decrease to an increase in the SNR or vice versa. Two successive SNR reversal points marked the boundaries of an excursion. The mid-points from 12 excursions (in dB SNR) were averaged to produce the adaptive SNR-50% measure (aSNR-50%).

Results

The aSNR-50% results were obtained from another 12 children aged 4.8–5.3 years with reported normal speech, language and hearing. The average 99% confidence interval (CI) of all participants’ mean aSNR-50% values was ±1.61 dB SNR; therefore, 3.22 dB SNR was the average critical difference required to confirm a significant difference in the scores obtained from the same participant between two test conditions. Statistically significant within-participant SRM was identified in 95% of the participants; in other words, aSNR-50% obtained from the spatially separated condition outperformed aSNR-50% obtained from the spatially co-located condition. The adaptive testing procedure was highly reliable, with an within-participant test-retest reliability of 90.6%. and significantly limited testing time to an average of 4.2 min. This research study has fulfilled its aim on detecting subtle within-participant SRM in very young children starting from 4 years of age with a reliable statistical procedure. MAPID-A offers a reliable and efficient clinical tool to investigate speech-recognition-in-noise and SRM performances in young Mandarin-speaking children.

Conclusions

The narrow CIs, high test-retest reliability, and short testing time has proven that the MAPID-A is a promising sensitive, reliable and time-efficient clinical tool to detect subtle within-participant speech-recognition-in-noise changes in children as young as 4–5 years. The MAPID-A offers a clinical tool to behaviorally track young children’s development in speech-recognition-in-noise and SRM, and to potentially review the development of the auditory neural pathway and the cerebral dominance for speech-recognition-in-noise in young children.

Tone perception in Mandarin-speaking school age children with otitis media with effusion

OBJECTIVES

The present study explored tone perception ability in school age Mandarin-speaking children with otitis media with effusion (OME) in noisy listening environments. The study investigated the interaction effects of noise, tone type, age, and hearing status on monaural tone perception, and assessed the application of a hierarchical clustering algorithm for profiling hearing impairment in children with OME.

METHODS

Forty-one children with normal hearing and normal middle ear status and 84 children with OME with or without hearing loss participated in this study. The children with OME were further divided into two subgroups based on their severity and pattern of hearing loss using a hierarchical clustering algorithm. Monaural tone recognition was measured using a picture-identification test format incorporating six sets of monosyllabic words conveying four lexical tones under speech spectrum noise, with the signal-to-noise ratio (SNR) conditions ranging from -9 to -21 dB.

RESULTS

Linear correlation indicated tone recognition thresholds of children with OME were significantly correlated with age and pure tone hearing thresholds at every frequency tested. Children with hearing thresholds less affected by OME performed similarly to their peers with normal hearing. Tone recognition thresholds of children with auditory status more affected by OME were significantly inferior to those of children with normal hearing or with minor hearing loss. Younger children demonstrated poorer tone recognition performance than older children with OME. A mixed design repeated-measure ANCOVA showed significant main effects of listening condition, hearing status, and tone type on tone recognition. Contrast comparisons revealed that tone recognition scores were significantly better under -12 dB SNR than under -15 dB SNR conditions and tone recognition scores were significantly worse under -18 dB SNR than those obtained under -15 dB SNR conditions. Tone 1 was the easiest tone to identify and Tone 3 was the most difficult tone to identify for all participants, when considering -12, -15, and -18 dB SNR as within-subject variables. The interaction effect between hearing status and tone type indicated that children with greater levels of OME-related hearing loss had more impaired tone perception of Tone 1 and Tone 2 compared to their peers with lesser levels of OME-related hearing loss. However, tone perception of Tone 3 and Tone 4 remained similar among all three groups. Tone 2 and Tone 3 were the most perceptually difficult tones for children with or without OME-related hearing loss in all listening conditions.

CONCLUSIONS

The hierarchical clustering algorithm demonstrated usefulness in risk stratification for tone perception deficiency in children with OME-related hearing loss. There was marked impairment in tone perception in noise for children with greater levels of OME-related hearing loss. Monaural lexical tone perception in younger children was more vulnerable to noise and OME-related hearing loss than that in older children.

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.

Optimization of the Dutch matrix test by random selection of sentences from a preselected subset

Matrix tests are available for speech recognition testing in many languages. For an accurate measurement, a steep psychometric function of the speech materials is required. For existing tests, it would be beneficial if it were possible to further optimize the available materials by increasing the function's steepness. The objective is to show if the steepness of the psychometric function of an existing matrix test can be increased by selecting a homogeneous subset of recordings with the steepest sentence-based psychometric functions. We took data from a previous multicenter evaluation of the Dutch matrix test (45 normal-hearing listeners). Based on half of the data set, first the sentences (140 out of 311) with a similar speech reception threshold and with the steepest psychometric function (≥9.7%/dB) were selected. Subsequently, the steepness of the psychometric function for this selection was calculated from the remaining (unused) second half of the data set. The calculation showed that the slope increased from 10.2%/dB to 13.7%/dB. The resulting subset did not allow the construction of enough balanced test lists. Therefore, the measurement procedure was changed to randomly select the sentences during testing. Random selection may interfere with a representative occurrence of phonemes. However, in our material, the median phonemic occurrence remained close to that of the original test. This finding indicates that phonemic occurrence is not a critical factor. The work highlights the possibility that existing speech tests might be improved by selecting sentences with a steep psychometric function.

Development of spatial release from masking in mandarin-speaking children with normal hearing

PURPOSE

This study investigated the development of spatial release from masking in children using closed-set Mandarin disyllabic words and monosyllabic words carrying lexical tones as test stimuli and speech spectrum-weighted noise as a masker.

METHOD

Twenty-six children ages 4-9 years and 12 adults, all with normal hearing, participated in speech recognition tests under 2 conditions: (a) speech and noise spatially mixed and presented from the front (NF), and (b) speech presented from the front with noise spatially separated and presented from the side (NS) with different signal-to-noise ratios (SNRs). Performance-SNR psychometric functions were obtained that generated the SNR for a 50% correct score (SNR-50%) as the outcome measure.

RESULTS

In the child participants, SNR-50% improved with age in NS but not NF. The difference in SNR-50% between NS and NF-the spatial release from masking (SRM)-increased with age with an average improvement of 0.1-0.15 dB per month.

CONCLUSIONS

SRM has a long developmental time, at least up to 9 years of age, which is significantly longer than some previous developmental studies have suggested. The child participants had not yet reached the adult SRM performance level. SRM is a potential clinical measure to reflect the maturation of spatial auditory processing.

Psychometric properties of the Standard-Chinese lexical neighborhood test

CONCLUSION

The psychometric characteristics of Standard-Chinese lexical neighborhood test (LNT) confirmed the lexical effects of the four word categories. The established normative baseline can be used in evaluating the word-recognition performance of the hearing-impaired listeners.

OBJECTIVES

The purpose of the present study was to examine the psychometric characteristics and evaluate the reliability of Standard-Chinese LNT in children and adults.

METHODS

Twenty-six normal-hearing adults and 13 normal-hearing children were recruited. Word recognition was tested with the Standard-Chinese LNT materials that consisted of four types of word list: monosyllable easy words, monosyllable hard words, disyllable easy words, and disyllable hard words.

RESULTS

The thresholds at 50% correct performance for the easy word lists and disyllable word lists were lower than those for the hard word lists and monosyllable word lists, respectively (all p < 0.001). The slopes for disyllable words were steeper than the monosyllable words (p < 0.05). In addition, the recognition threshold of the four categories for children was higher than that for adults (all p < 0.05). The critical difference was on average 26.6% for adults and 30.0% for children.

The Effect of Dialect on Speech Audiometry Testing

Purpose

In this study, the authors examined the validity of using materials from 2 nonregional yet mutually intelligible dialects to evaluate an individual's speech recognition threshold (SRT) and word recognition (WR) abilities and whether a speaker of 1 dialect could accurately administer and score materials in the other dialect.

Method

Previously created SRT and WR materials were presented to 32 Mandarin listeners with normal hearing: 16 speakers of Mainland Mandarin and 16 speakers of Taiwan Mandarin. Hearing abilities were examined using SRT and WR materials created for speakers from 2 different regional dialects. Presentation of the materials occurred during 2 test sessions, counterbalanced across material and listener dialect. Listener responses were evaluated by 2 judges; 1 spoke Mainland Mandarin, and the other spoke Taiwan Mandarin.

Results

For the SRT and WR results, differences in listener performance were statistically significant across material and listener dialect, with threshold differences of less than 2 dB HL when collapsed across session. The interscorer percentage of agreement was 99.5% for SRT and 99.1% for WR testing.

Conclusion

Testing with materials in a different regional dialect does have a measurable impact on SRT and WR performance. However, this difference, though reliable, is small enough to have a negligible impact on clinical findings.

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.

VTMR, a new speech audiometry test with verbal tasks and motor responses

OBJECTIVES

The aim of this study was to design a complementary speech audiometry test using verbal tasks and motor responses (VTMR) to assess the ability of a subject to understand and perform simple motor tasks with 3-dimensional objects, to describe its construction, and to show the preliminary results of a pilot study on the Italian version of the test.

METHODS

The items used in the test setting included 1 base, 1 hammer, 1 wooden structure with 4 sticks, and 5 rings of different colors and 20 lists with 5 verbal tasks per list. The VTMR test and bisyllabic speech audiometry were evaluated in normal-hearing subjects with and without cognitive impairment and in subjects with sensorineural hearing loss.

RESULTS

All normal-hearing subjects without cognitive impairment performed the VTMR tasks (100%) correctly at 35 dB sound pressure level. In subjects with sensorineural hearing loss, the percentage of correct answers was significantly higher for the VTMR test than for bisyllabic speech audiometry above 50 dB sound pressure level. This percentage was higher for the VTMR also in normal-hearing subjects with poor cognitive skills.

CONCLUSIONS

The VTMR might make it easier to check patients' ability to understand verbal commands than does traditional speech audiometry, in particular in those patients with poor test-taking skills.

Development of a Mandarin monosyllable test material with homogenous items (I): homogeneity selection

CONCLUSION

A homogeneity selection could establish a homogenous resource for Chinese Mandarin monosyllabic test lists.

OBJECTIVE

This study aimed to develop a set of succinct and phonemically balanced monosyllabic Mandarin recognition test lists with good item homogeneity, in an effort to meet the need for Chinese Mandarin speech recognition test materials.

METHODS

In reference to the Chinese phonemes distribution probability, we developed the Phoneme Allocation Table, which decided the occurrence of all consonants, vowels, and semantic tones in each list. A total of 489 monosyllables were selected and organized into 30 lists, with 25 monosyllables in each. A two-factor design was used to screen homogenous items out. Sixty normal-hearing native Mandarin speakers participated in experiment. The performance-intensity (P-I) function curve of each test item was fit by logistic regression. Items were screened out as homogenous ones using the following criteria: 1) regression R value was not <0.9; 2) slope was between 2%/dB and 12%/dB; 3) threshold was between -8 dB HL and 10 dB HL.

RESULTS

The Phoneme Allocation Table was established as a framework of 30 lists, providing a basis on which phonemically balanced monosyllabic lists can be developed. In all, 342 monosyllables with good homogeneity were screened out and can be reorganized to establish monosyllabic test lists with good sensitivity.

Psychometrically equivalent trisyllabic words for speech reception threshold testing in Mandarin

The aim of this investigation was to develop, digitally record, evaluate, and equate Mandarin trisyllabic words, which could then be used to measure the SRT. A selection of 90 frequently utilized trisyllabic words were digitally recorded by male and female talkers of Standard Mandarin and presented to 20 normally hearing subjects at 13 intensity levels (-10 to 14dB HL) in 2dB increments. Using logistic regression, psychometric functions were then calculated for all words. Twenty-four trisyllabic words with steep psychometric function slopes were selected, and their intensities were digitally adjusted to match the mean subject PTA (3.0 dB HL). The mean slopes for the 24 selected male and female trisyllabic Mandarin Chinese words were 11.3%/dB and 12.1%/dB, respectively. Thus we developed a list of words which were homogeneous with respect to audibility and slope. Digital recordings of the psychometrically equivalent trisyllabic words are available on compact disc.

Development of speech reception threshold materials for speakers of Taiwan Mandarin

The aim of this research was to develop, digitally record, evaluate, and equate speech audiometry materials that can be used to measure the speech reception threshold (SRT) in quiet for native speakers of Taiwan Mandarin. Familiar trisyllabic words were digitally recorded by male and female talkers of Taiwan Mandarin and subsequently evaluated by 20 native listeners with normal hearing at 14 intensity levels (-10 to 16 dB HL) in 2 dB increments. Using logistic regression, psychometric functions were calculated for all words. Twenty-eight words with comparatively steep psychometric functions were selected and digitally adjusted to match the mean subject pure-tone average (5.0 dB HL). This resulted in a list of words that are relatively homogeneous in threshold audibility and psychometric function slope. The mean slopes for the 28 selected male and female trisyllabic Taiwan Mandarin words were 11.3%/dB and 11.7%/dB, respectively.

Development of the computerized Cantonese disyllabic lexical tone identification test in noise (CANDILET-N)

CANDILET-N is a closed-set speech-recognition test to assess lexical tone recognition in noise for Cantonese speakers. The test consists of 60 test items in a four-alternative forced-choice test paradigm, with male and female speaker versions. Each test plate consists of two disyllabic-word lexical tone minimal pair test items and their respective phonemic distracters. Psychometric performance SNR (signal-to-noise ratio) functions from 26 normal hearing adult subjects were fitted to a logistic regression model to obtain the SNR for 50% correct score (SNR-50%) for individual test items. The mean SNR-50% of the 60 test items for the female and male test sets were -10.3 dB and -11.1 dB, respectively. The SNR-50% varies across test items and their SNR need to be adjusted to improve the homogeneity among them.

Word Recognition Materials for Native Speakers of Taiwan Mandarin

Purpose

To select, digitally record, evaluate, and psychometrically equate word recognition materials that can be used to measure the speech perception abilities of native speakers of Taiwan Mandarin in quiet.

Method

Frequently used bisyllabic words produced by male and female talkers of Taiwan Mandarin were digitally recorded and subsequently evaluated using 20 native listeners with normal hearing at 10 intensity levels (−5 to 40 dB HL) in increments of 5 dB.

Results

Using logistic regression, 200 words with the steepest psychometric slopes were divided into 4 lists and 8 half-lists that were relatively equivalent in psychometric function slope. To increase auditory homogeneity of the lists, the intensity of words in each list was digitally adjusted so that the threshold of each list was equal to the midpoint between the mean thresholds of the male and female half-lists.

Conclusions

Digital recordings of the word recognition lists and the associated clinical instructions are available on CD upon request.