The Adaptation to Mandarin-Accented English by Older, Hearing-Impaired Listeners Following Brief Exposure to the Accent.

Purpose The language processing of Mandarin-accented English (MAE) by older hearing-impaired (OHI), older normally hearing (NH), and younger NH listeners was explored. We examined whether OHI adults have more difficulty than NH listeners in recognizing and adapting to MAE speech productions after receiving brief training with the accent. Method Talker-independent adaptation was evaluated in an exposure training study design. Listeners were trained either by four MAE talkers or four Australian English talkers (control group) before listening to sentences presented by a novel MAE talker. Speech recognition for both the training sentences and the experimental sentences were compared between listener groups and between the training accents. Results Listeners in all three groups (OHI, older NH, younger NH) who had been trained by the MAE talkers showed higher odds of speech recognition than listeners trained by the Australian English talkers. The OHI listeners adapted to MAE to the same degree as the NH groups despite returning lower overall odds of recognizing MAE speech. Conclusions Older listeners with mild-to-moderate hearing loss were able to benefit as much from brief exposure to MAE as did the NH groups. This encouraging result suggests that OHI listeners have access to and can exploit the information present in a relatively brief sample of accented speech and generalize their learning to a novel MAE talker.

Perception of Cantonese Lexical Tones by Pediatric Cochlear Implant Users.

Purpose: The purpose of this study is to assess Cantonese word recognition and the discrimination of Cantonese tones with manipulated contours by child and adolescent cochlear implant (CI) users and a group of peers with normal hearing (NH). It was hypothesized that the CI users would perform more poorly than their counterparts with NH in both tasks and that CI users implanted before 2 years of age would perform better than those implanted after 2 years. Method: Forty-one participants were recruited from hospitals, schools, and kindergartens in Hong Kong: Ten CI users implanted at or before 2 years of age ("early" CI group), 13 CI users implanted after 2 years of age ("late" CI group), and 18 individuals with NH. The mean age at implantation of the early CI group was 1.5 years (SD = 0.3), and for the late CI group, it was 4.3 years (SD = 2.1). Participants were a mean of 13.3 years of age (SD = 3.7) at time of testing. Participants completed a Cantonese word recognition test and a discrimination task using Cantonese tones with modified fundamental frequency trajectories. Results: Both CI user groups obtained significantly lower scores than the group with NH on the word recognition test. Mean percent correct scores for the word recognition test were 79% for the early CI group, 69% for the late CI group, and 97% for the group with NH. The group with NH consistently achieved higher scores than the CI user groups when discriminating manipulated Cantonese tones. Increasing the acoustic difference between tones improved discrimination performance for CI users for level tone contrasts only. CI users implanted at or before 2 years of age obtained higher scores than those implanted later. Conclusions: The results of this study add further evidence that children using CIs do not perform as well as peers in perceiving Cantonese tones. Modification of tones to increase pitch range did not consistently improve the ability of children with implants to perceive the difference between tones. Further research is required to fully assess potential benefits of early implantation for speakers of tonal languages. Supplemental Materials: https://doi.org/10.23641/asha.5782209.

Cantonese Tone Perception for Children Who Use a Hearing Aid and a Cochlear Implant in Opposite Ears.

OBJECTIVES: The ability to recognize tones is vital for speech perception in tonal languages. Cantonese has six tones, which are differentiated almost exclusively by pitch cues (tones 1 to 6). The differences in pitch contours among the tones are subtle, making Cantonese a challenging language for cochlear implant users. The addition of a hearing aid has been shown to improve speech perception in nontonal languages and in Mandarin Chinese. This study (1) investigates the Cantonese tone perception ability of children who use a cochlear implant and a hearing aid in opposite ears; (2) evaluates the effect of varying pitch height and pitch contour cues on Cantonese tone perception for these children; and (3) compares the Cantonese tone perception ability for using a hearing aid and a cochlear implant together versus an implant alone. DESIGN: Eight native Cantonese speaking children using a cochlear implant and a hearing aid in opposite ears were assessed for tone perception and word identification. The tone perception test involved discriminating and ranking tone pairs from natural and artificially manipulated Cantonese tones with various pitch heights and/or pitch contours. The word identification test involved identifying Cantonese words in a four-alternative forced-choice task. All tests were performed in two device conditions: (1) cochlear implant and hearing aid together and (2) implant alone. RESULTS: Seven of the 8 subjects performed significantly above chance in both tests using the cochlear implant alone. Results showed that both pitch height and/or pitch direction were important perceptual cues for implant users. Perception for some tones was improved by increasing the pitch height differences between the tones. The ability to discriminate and rank the tone 2/tone 5 contrast and the tone 4/tone 6 contrast was poor, as the tones in these contrasts are similar in pitch contours and onset frequencies. No significant improvement was observed after artificially increasing the pitch offset differences between the tones in the tone 2/tone 5 and the tone 4/tone 6 contrasts. Tone perception results were significantly better with the addition of the hearing aid in the nonimplanted ear compared with using the implant alone; however, word identification results were not significantly different between using the implant alone and using both the hearing aid and the implant together. None of the subjects performed worse in tone perception or in word identification when the hearing aid was added. CONCLUSIONS: Reduced ability to perceive pitch contour cues, even when artificially exaggerated, may explain some of the difficulties in Cantonese word recognition for implant users. The addition of a contralateral hearing aid could be beneficial for Cantonese tone perception for some individuals with a unilateral implant. The results encouraged Cantonese speakers to trial a hearing aid in the nonimplanted ear when using a cochlear implant.

Discourse Strategies and the Production of Prosody by Prelingually Deaf Adolescent Cochlear Implant Users.

OBJECTIVES: The purpose of this study is to assess the use of discourse strategies and the production of prosody by prelingually deaf adolescent users of cochlear implants (CIs) when participating in a referential communication task. We predict that CI users will issue more directives (DIRs) and make less use of information requests (IRs) in completing the task than their normally hearing (NH) peers. We also predict that in signaling these IRs and DIRs, the CI users will produce F0 rises of lesser magnitude than the NH speakers. DESIGN: Eight prelingually deaf adolescent CI users and 8 NH adolescents completed a referential communication task, where participants were required to direct their interlocutor around a map. Participants were aged from 12.0 to 14.2 years. The mean age at implantation for the CI group was 2.1 years (SD 0.9). The use of IRs, DIRs, acknowledgments, and comments was compared between the two groups. The use and magnitude of fundamental frequency (F0) rises on IRs and DIRs was also compared. RESULTS: The CI users differed from the NH speakers in how they resolved communication breakdown. The CI users showed a preference for repeating DIRs, rather than seeking information as did the NH speakers. A nonparametric Mann-Whitney U test indicated that the CI users issued more DIRs (U = 8, p = 0.01), produced fewer IRs (U = 13, p = 0.05) and fewer acknowledgments (U = 5, p = 0.003) than their NH counterparts. The CI users also differed in how they used F0 rises as a prosodic cue to signal IRs and DIRs. The CI users produced larger F0 rises on DIRs than on IRs, a pattern opposite to that displayed by the NH speakers. An independent samples t-test revealed that the CI users produced smaller rises on IRs compared with those produced by the NH speakers [t(12) = -2.762, p = 0.02]. CONCLUSIONS: The CI users differed from the NH speakers in how they resolved communication breakdown. The CI users showed a preference for repeating DIRs, rather than seeking information to understand their interlocutor's point of view. Their use of prosody to signal discourse function also differed from their NH peers. These differences may indicate a lack of understanding of how prosody is used to signal discourse modality by the CI users. This study highlights the need for further research focused on the interaction of prosody, discourse, and language comprehension.

The Use of Prosodic Cues in Sentence Processing by Prelingually Deaf Users of Cochlear Implants.

OBJECTIVES: The purpose of this study is to assess the use of prosodic and contextual cues to focus by prelingually deaf adolescent users of cochlear implants (CIs) when identifying target phonemes. We predict that CI users will have slower reaction times to target phonemes compared with a group of normally-hearing (NH) peers. We also predict that reaction times will be faster when both prosodic and contextual (semantic) cues are provided. DESIGN: Eight prelingually deaf adolescent users of CIs and 8 adolescents with NH completed 2 phoneme-monitoring experiments. Participants were aged between 13 and 18 years. The mean age at implantation for the CI group was 1.8 years (SD: 1.0). In the prosodic condition, reaction times to a target phoneme in a linguistically focused (i.e., stressed) word were compared between the two groups. The semantic condition compared reaction time with target phonemes when contextual cues to focus were provided in addition to prosodic cues. RESULTS: Reaction times of the CI group were slower than those of the NH group in both the prosodic and semantic conditions. A linear mixed model was used to compare reaction times using Group as a fixed factor and Phoneme and Subject as random factors. When only prosodic cues (prosodic condition) to focus location were provided, the mean reaction time of the CI group was 512 msec compared with 317 msec for the NH group, and this difference was significant (p < 0.001). The provision of contextual cues speeded reaction times for both groups (semantic condition), indicating that top-down processing aided both groups in their search for a focused item. However, even with both prosodic and contextual cues, the CI users' processing times remained slower, compared with the NH group, with mean reaction times of 385 msec for the CI users but 232 msec for the NH listeners (p < 0.001). CONCLUSIONS: Prelingually deaf CI users' processing of prosodic cues is less efficient than that of their NH peers, as evidenced by slower reaction times to targets in phoneme monitoring. The provision of contextual cues speeded reaction times for both NH and CI groups, although the CI users were slower in responding than the NH group. These findings contribute to our understanding of how CI users employ/integrate prosodic and semantic cues in speech processing.

Discrimination of intonation contours by adolescents with cochlear implants.

OBJECTIVE: Differences in fundamental frequency (F0) contour peak alignment contribute to the perception of pitch accents in speech intonation. The present study assessed the discrimination of differences in F0 contour peak alignment by adolescent users of cochlear implants (CIs). DESIGN: In Experiment 1, subjects discriminated between rise-fall F0 contours located early in the syllable and those aligned late. Recorded utterances with manipulated F0 were used as stimuli and all subjects wore a unilateral CI. In Experiment 2, bilaterally-implanted subjects repeated Experiment 1 in the bilateral condition. STUDY SAMPLE: Twenty-one CI users aged 12-21 years participated. A normally-hearing control group (n = 20) also completed Experiment 1. RESULTS: Listeners with normal hearing (NH) could discriminate between F0 peaks differing by 80 ms or more. Results varied among the CI users, with only four users displaying a pattern of results similar to that of the NH listeners. Sixteen CI users responded inconsistently or at chance levels (p > 0.05; binomial test). Ten CI users who were bilaterally implanted completed the tests in unilateral and bilateral listening conditions. CONCLUSIONS: Results suggest that CI users may have difficulty discriminating between F0 alignment and that use of bilateral implants did not provide an advantage to discrimination.

Actor vocal training for the habilitation of speech in adolescent users of cochlear implants.

This study examined changes to speech production in adolescents with hearing impairment following a period of actor vocal training. In addition to vocal parameters, the study also investigated changes to psychosocial factors such as confidence, self-esteem, and anxiety. The group were adolescent users of cochlear implants (mean age at commencement of training 15.9 years), with approximately half of the group wearing a hearing aid in the contralateral ear. The mean age of implantation of the group was 7.6 years and the participants displayed a range of speech production abilities. Evaluation of posttraining outcomes was performed via a combination of perceptual and acoustic analyses. Significant posttraining changes to vocal parameters included increased pitch range and variability and decreased speaking rate. From a psychosocial perspective, posttraining stress levels were significantly lowered. This study suggested that actor vocal training may benefit young people with hearing impairment, both in the way in which they use their voices and in the way in which they view themselves.

Spoken language development in oral preschool children with permanent childhood deafness.

This article documented spoken language outcomes for preschool children with hearing loss and examined the relationships between language abilities and characteristics of children such as degree of hearing loss, cognitive abilities, age at entry to early intervention, and parent involvement in children's intervention programs. Participants were evaluated using a combination of the Child Development Inventory, the Peabody Picture Vocabulary Test, and the Preschool Clinical Evaluation of Language Fundamentals depending on their age at the time of assessment. Maternal education, cognitive ability, and family involvement were also measured. Over half of the children who participated in this study had poor language outcomes overall. No significant differences were found in language outcomes on any of the measures for children who were diagnosed early and those diagnosed later. Multiple regression analyses showed that family participation, degree of hearing loss, and cognitive ability significantly predicted language outcomes and together accounted for almost 60% of the variance in scores. This article highlights the importance of family participation in intervention programs to enable children to achieve optimal language outcomes. Further work may clarify the effects of early diagnosis on language outcomes for preschool children.