Lexical Tone Research Articles

Event-related potentials of familiar monosyllabic words with unexpected lexical tones: A picture-word study of Mandarin-speaking preschoolers with and without a history of late talking.

This study examined how Mandarin-speaking preschoolers with and without a history of late talking (LT) process familiar monosyllabic words with unexpected lexical tones, focusing on both phonological and semantic violations. This study initially enrolled 64 Mandarin-speaking toddlers: 31 with a history of LT (mean age: 27.67 months) and 33 without a history of LT (non-LT) (mean age: 27.85 months). Event-related potentials were recorded at the age of 4 years during a picture-word mismatch task (LT mean age: 51.36 months; non-LT mean age: 51.20 months); in this task, the participants were presented with auditory words either matching (Tone 3) or mismatching with images in terms of their lexical tones; the mismatches encompassed acoustically dissimilar (Tone 1) and similar (Tone 2) mismatches. A significant difference in the phonological mapping negativity (PMN) responses to Tones 1 and 3 was observed only in the non-LT group. However, differences in the N400 responses to Tones 1 and 3 remained consistent across both groups. In addition, greater differences in the PMN responses between Tones 1 and 3 were associated with higher language proficiency during the preschool period. The PMN response serves as an indicator of neural correlates in lexical tone processing, reflecting challenges encountered by preschoolers with a history of LT when processing the lexical tones of familiar words. Furthermore, the PMN response was correlated with concurrent language abilities. These findings indicate the importance of early tonal perception development for Mandarin speakers with a history of LT. RESEARCH HIGHLIGHTS: Preschoolers with a history of late talking (LT), similar to preschoolers without such a history, can establish word expectations and detect the lexical tone violation in real time. However, those with a history of LT require additional time to process acoustic cues and differentiate between word semantics based on lexical tone information. The phonological mapping negativity response serves as an indicator of neural correlates in lexical tone processing, reflecting challenges encountered by preschoolers with a history of LT when processing the lexical tones of familiar words. The present findings indicate the importance of early intervention for Mandarin speakers with a history of LT, with an emphasis on lexical tone processing from toddlerhood.

The combined effects of bilingualism and musicianship on listeners’ perception of non-native lexical tones

Non-native lexical tone perception can be affected by listeners’ musical or linguistic experience, but it remains unclear of whether there will be combined effects and how these impacts will be modulated by different types of non-native tones. This study adopted an orthogonal design with four participant groups, namely, Mandarin-L1 monolinguals and Mandarin-L1 and Cantonese-L2 bilinguals with or without musical training, to investigate effects of bilingualism and musicianship on perception of non-native lexical tones. The closely matched four groups, each encompassing an equal number of 20 participants, attended a modified ABX discrimination task of lexical tones of Teochew, which was unknown to all participants and consists of multiple tone types of level tones, contour tones, and checked tones. The tone perceptual sensitivity index of d’ values and response times were calculated and compared using linear mixed-effects models. Results on tone sensitivity and response time revealed that all groups were more sensitive to contour tones than level tones, indicating the effect of native phonology of Mandarin tones on non-native tone perception. Besides, as compared to monolinguals, bilinguals obtained a higher d’ value when discriminating non-native tones, and musically trained bilinguals responded faster than their non-musician peers. It indicates that bilinguals enjoy a perceptual advantage in non-native tone perception, with musicianship further enhancing this advantage. This extends prior studies by showing that an L2 with a more intricate tone inventory than L1 could facilitate listeners’ non-native tone perception. The pedagogical implications were discussed.

Auditory perceptual ability affects dichotic listening performance in older adults

ABSTRACT Age-related changes pose challenges in speech processing for older adults. However, little is known about the role of auditory perceptual ability in their performance in dichotic listening tasks. The present study investigated how older adults’ auditory perceptual abilities affected their correct rates and the right ear advantage (REA) in the dichotic listening tasks in two experiments. In Experiment 1, older adults’ performance was assessed using dichotic listening tasks based on consonant–vowel (CV) words varying in consonants, vowels, and lexical tones, each presenting distinct auditory perceptual demands. It was found that older adults exhibited decreased correct rates as auditory perceptual demands increased. Moreover, differences in the REA were observed in older listeners, suggesting increased engagement of the hemisphere responsible for acoustic analysis in processing challenging dichotic stimuli. Experiment 2 examined how older individuals’ acoustic processing abilities contributed to their dichotic listening performance. It was shown that older adults with acoustic processing abilities comparable to those of younger individuals demonstrated correct rates and REAs similar to those of younger cohorts. These results revealed the nonnegligible role of acoustic processing in the dichotic listening paradigm and the significance of considering listeners’ auditory perceptual abilities in investigating language lateralisation using the dichotic listening paradigm.

Neural processing of Mandarin and Cantonese lexical tone alternations: implications for the nature of phonological representations

This study provides neurocognitive evidence to shed further insight into the architecture of phonological representations. We tap into these representations by focusing on the neural processing of phonological alternations. Traditional generative accounts postulate abstract representations which are transformed by phonological processes into different alternants. Recent psycholinguistically-based frameworks posit that different alternants are listed in parallel in the abstract representation. Exemplar-based theories posit that alternation is a manifestation of frequency effects among concrete phonetic forms stored in memory. However, it is unclear the extent to which phonological representations of different levels of abstractedness are neurocognitive realities, beyond formal entities for linguistic analysis. This study tests the hypothesis that phonological representations are neurocognitive primitives that modulate speech processing and lexical access. We examined the processing of two surface-similar, but distributionally distinct lexical tone alternation patterns in Mandarin and Cantonese. With a cross-modal priming paradigm, differential neurophysiological components (LPC vs. N400) associated with the processing of alternation violations were identified cross-linguistically. Results support our hypothesis, suggesting that cross-linguistically distinct abstract phonological representations differentially modulate phonotactic detection, lexical access, and phonological restructuring processes. Results also lend theoretical insight into the multiform nature of the phonological representation, which encompasses both abstract and concrete levels of representations.

Production of Mandarin and Fuzhou lexical tones in six- to seven-year-old Mandarin-Fuzhou bilingual children

AbstractThis study investigated the production of Mandarin and Fuzhou lexical tones by Mandarin-Fuzhou bilingual children. Forty children aged 6;11 to 7;6 and two groups of adults (Mandarin speakers and Fuzhou speakers) were asked to produce pre-selected familiar monosyllabic words. Adult judges' perceptual judgments and acoustic analysis showed that: (1) overall, these children's production performance of Mandarin tones was similar to adults', with very high accuracy; (2) children did not reach adult-like production competence in Fuzhou tones by age 7;6; and (3) there was an imbalance in children's development of the seven lexical tones in Fuzhou. Children's late and unbalanced development of Fuzhou tones could be ascribed to their unbalanced Mandarin-Fuzhou exposure, and it is argued that children might transfer the characteristics of the Mandarin tonal system to their production of Fuzhou tones.

High variability phonetic training facilitates perception-to-production transfer in Mandarin-speaking children with cochlear implants: An acoustic investigation.

This study primarily aimed to evaluate the effectiveness of high variability phonetic training (HVPT) for children with cochlear implants (CIs) via the cross-modal transfer of perceptual learning to lexical tone production, a scope that has been largely neglected by previous training research. Sixteen CI participants received a five-session HVPT within a period of three weeks, whereas another 16 CI children were recruited without receiving any formal training. Lexical tone production was assessed with a picture naming task before the provision (pretest) and immediately after (posttest) and ten weeks after (follow-up test) the completion of the training protocol. The production samples were coded and analyzed acoustically. Despite considerable distinctions from the typical baselines of normal-hearing peers, the trained CI children exhibited significant improvements in Mandarin tone production from pretest to posttest in pitch height of T1, pitch slope of T2, and pitch curvature of T3. Moreover, the training-induced acoustic changes in the concave characteristic of the T3 contour was retained ten weeks after training termination. This study represents an initial acoustic investigation on HVPT-induced benefits in lexical tone production for the pediatric CI population, which provides valuable insights into applying this perceptual training technique as a viable tool in clinical practices.

A cross-linguistic review of citation tone production studies: Methodology and recommendations.

The study of citation tones, lexical tones produced in isolation, is one of the first steps towards understanding speech prosody in tone languages. However, methodologies for investigating citation tones vary significantly, often leading to limited comparability of tone inventories, both within and across languages. This paper presents a systematic review of research methods and practices in 136 citation tone studies on 129 tonal language varieties in China, including 99 studies published in Chinese, which are therefore not easily available to an international scientific readership. The review provides an overview of possible analytical decisions along the research pipeline, and unveils considerable variation in data collection, analysis, and reporting conventions, particularly in how f0, the primary acoustic correlate for tone, is operationalised and reported across studies. Key methodological issues are identified, including small sample sizes and inadequate transparency in communicating methodological decisions and procedure. This paper offers a clear road map for citation tone production research and proposes a range of recommendations on speaker sampling, experimental design, acoustic processing techniques, f0 analysis, and result reporting, with the goal of facilitating future tonal research and enhancing resources for underrepresented tonal varieties.

High variability phonetic training facilitates categorical perception of Mandarin lexical tones in L2 older adults: A link to auditory processing

The current study investigated the facilitatory effects of High Variability Phonetic Training (HVPT) in second language (L2) categorical perception (CP) of Mandarin lexical tones. It also explored whether and how individual differences in auditory processing predicted gains from such training. The participants were 32 native English-speaking adults aged over 60 years who were learning Mandarin Chinese as their L2. They were randomly divided into the HVPT group (HG) ( n = 16) and the control group (CG) ( n = 16). Their L2 CP performance was assessed through an identification task and discrimination task before training, immediately after training, and two months later. Auditory processing tests were also conducted to measure the participants’ ability to encode spectral and temporal details of sounds. Linear mixed-effects (LME) models showed that, compared to the CG, the HG exhibited a more pronounced improvement in tonal categorization. Furthermore, regression analysis confirmed that individual differences in perceptual acuity significantly predicted gains from training in L2 CP of Mandarin lexical tones.

Cross-Linguistic Nasalance Comparisons: A Review of Speech Sample Sets and Preliminary Consideration of Effect of Lexical Tone.

Nasalance is an acoustic representation of perceived nasality with proven clinical and research utility. Its validity is contingent on appropriate speech sample sets and distinct normative databases based on known impact factors such as language and phonetic environment, but little is known about the potential effects of lexical tone on nasalance. Its use in international cross-linguistic studies necessitates definition and added considerations of speech sampling protocol. Part I. A methodological review was undertaken using PRISMA (2020), the Scottish Intercollegiate Guidelines Network (SIGN) Methodology Checklist for evaluating risk of bias, and calculation of effect sizes and/or visual displays using tables showing grouping of similar data for synthesis of findings. Part II. A pilot study explored the effect of lexical tone on nasalance in Cantonese, a lexical tone language. Part I. 17 studies met the inclusion criteria. In addressing possible confounders and minimizing risk of bias, 13 studies were assigned an overall quality rating of (+) acceptable and the remaining 4, a high rating (++). For the 9-word string, there was a (non-clinical) difference of 3-5% between Swedish and Brazilian-Portuguese, and a moderate effect size for age (d=0.49); for the consonant-vowel syllables set (CV set), clinical differences across languages were identified for adults, and between 5-10% for children and adolescents. Part II. The pilot study showed a significant effect of lexical tone on nasalance where nasalance for the high-level tone 1 was significantly higher than that for high-rising tone 2, low-rising tone 5, and low-falling tone 4. There is a need for further evidence from other languages, including tonal languages, to better define the evidence and speech methodology of international cross-linguistic nasalance studies.

Could L1 intonation patterns be applied in teaching Mandarin tones to atonal learners of Chinese? – An acoustic phonetic study

Abstract This study focuses on the acoustic comparison of Mandarin Chinese lexical tones and Hungarian monosyllabic intonation patterns. The aim of this experiment was to explore whether atonal L1 intonation patterns are applicable in teaching tones in L2 Mandarin Chinese, and also to investigate to what extent atonal and tonal monosyllabic contours differ. Mandarin Chinese rising Tone 2 is compared to two corresponding Hungarian rising contours: i) monosyllabic interrogative contour and ii) the rising phase of the f 0 pattern in alternative questions. Mandarin Chinese falling Tone 4 is likewise compared to Hungarian i) declarative and ii) imperative f 0 curves. We compared Mandarin Chinese and Hungarian native speakers’ production regarding five acoustic features. Results show that Mandarin Chinese Tone 2 is articulated with longer duration, and a more concave f 0 curve compared to Hungarian rising intonation patterns. Mandarin Chinese Tone 4, on the other hand, was found to differ from the Hungarian imperative contour only in terms of the f 0 curve shape, since Tone 4 featured a more domed curve. Hungarian declaratives are characterized by a more concave f 0 pattern, realized in a lower f 0 range compared to Tone 4. The results of this study may contribute to the proper application of atonal intonation patterns in L2 teaching of Mandarin Chinese through the differences and similarities between atonal and tonal monosyllabic f 0 patterns.

Acoustic patterns in Hong Kong Cantonese hesitation markers: Vowel quality and omnisyllabic tone

ABSTRACT: Hesitation markers (HMs) lie somewhere on the dividing line between linguistic and sub-linguistic, evincing at the same time crosslinguistic commonalities as well as language-specific features (Candea et al. 2005; Dingemanse and Woensdregt 2020). This study seeks to expand on understanding of these lexically peripheral items by analyzing their acoustic properties in Hong Kong Cantonese (HKCT), including vowel quality and F0. Recent work by Dingemanse and Woensdregt (2020) discusses phonetic similarities in HMs across languages, which are constrained by adherence to the phonologies of their respective languages. However, it is unclear how HMs are incorporated into HKCT tonal phonology, which can be characterized as 'omnisyllabic' (Matisoff 1995), every syllable being associated with a lexical tone. The present study gathers acoustic data (F0, F1–F2, duration) from the PolyU Corpus of Spoken Chinese (http://wongtaksum.no-ip.info:81/corpus.htm) across 10 speakers and 196 HMs, comparing them against 525 lexical items. Results for F1–F2 clustered around mid-front /ɛ/, which is in line both with crosslinguistic trends and HKCT phonology. Results for F0 clustered around the lower end of the pitch range, approaching Tones 3 and 6, which is expected given effort minimization trends. However, establishing a connection with a particular lexical tone was complicated by the similarity of Tones 3 and 6, which could not be statistically distinguished. Cross-speaker analysis showed considerable variation in F0, indicating that context, intonation, or idiolectal variation may play a substantial role. This has implications for our understanding of how peripheral items like hesitation markers are treated in omnisyllabic tone languages like Cantonese. 摘要: 犹豫标记置身语言学与副语言学的边界，占据一个既有跨语言共性又 具特定语言特征的区域(Candea et al. 2005; Dingemanse and Woensdregt 2020)。本研究旨在透过分析犹豫标记在香港粤语中，包含元音音色 及 F0 的声学特性，扩充对这些语义周边项目的理解。Dingemanse and Woensdregt(2020)最近的研究论及犹豫标记有跨语言声学相似性，亦 受制于各语言对自身的音段音韵学的持守。不过，香港粤语作为"全 音节语言"(Matisoff 1995)，每个音节均附上声调，犹豫标记应如何 纳入香港粤语的声调音韵学，这仍不清楚。本研究从理工大学中文口 语语料库 (PolyU Corpus of Spoken Chinese, http://wongtaksum.noip.info:81/corpus.htm) 集结 F0、 F1–F2 及时长的声学资料，横跨十位语 者，共 196 个犹豫标记，与 525 个词汇作比较分析。F1–F2 的结果围 绕半开前元音/ɛ/丛集，与跨语言趋势及香港粤语音韵学均能匹配。F0 的结果则丛集于近乎最低的音高，接近调三及调六，合乎最少付出倾 向的预想。可是，要与特定字词声调建立联系仍很复杂，因为调三及 调六相似，不能以统计学区分。跨语者分析显示 F0 有相当变化，提示 语境、语调或个人习语变化可能有重大影响。这对理解全音节语言 (如粤语)如何应对犹豫标记等等周边项目有所提示。

Learning lexical tone through statistical learning in non-tone language speakers

Learning lexical tone through statistical learning in non-tone language speakers

Outcomes Using the Optimized Pitch and Language Strategy Versus the Advanced Combination Encoder Strategy in Mandarin-Speaking Cochlear Implant Recipients.

The experimental Optimized Pitch and Language (OPAL) strategy enhances coding of fundamental frequency (F0) information in the temporal envelope of electrical signals delivered to channels of a cochlear implant (CI). Previous studies with OPAL have explored performance on speech and lexical tone perception in Mandarin- and English-speaking CI recipients. However, it was not clear which cues to lexical tone (primary and/or secondary) were used by the Mandarin CI listeners. The primary aim of the present study was to investigate whether OPAL provides improved recognition of Mandarin lexical tones in both quiet and noisy environments compared with the Advanced Combination Encoder (ACE) strategy. A secondary aim was to investigate whether, and to what extent, removal of secondary (duration and intensity envelope) cues to lexical tone affected Mandarin tone perception. Thirty-two CI recipients with an average age of 24 (range 7 to 57) years were enrolled in the study. All recipients had at least 1 year of experience using ACE. Each subject attended two testing sessions, the first to measure baseline performance, and the second to evaluate the effect of strategy after provision of some take-home experience using OPAL. A minimum take-home duration of approximately 4 weeks was prescribed in which subjects were requested to use OPAL as much as possible but were allowed to also use ACE when needed. The evaluation tests included recognition of Mandarin lexical tones in quiet and in noise (signal to noise ratio [SNR] +5 dB) using naturally produced tones and duration/intensity envelope normalized versions of the tones; Mandarin sentence in adaptive noise; Mandarin monosyllabic and disyllabic word in quiet; a subset of Speech, Spatial, and Qualities of hearing questionnaire (SSQ, speech hearing scale); and subjective preference for strategy in quiet and noise. For both the natural and normalized lexical tone tests, mean scores for OPAL were significantly higher than ACE in quiet by 2.7 and 2.9%-points, respectively, and in noise by 7.4 and 7.2%-points, respectively. Monosyllabic word recognition in quiet using OPAL was significantly higher than ACE by approximately 7.5% points. Average SSQ ratings for OPAL were significantly higher than ACE by approximately 0.5 points on a 10-point scale. In quiet conditions, 14 subjects preferred OPAL, 7 expressed a preference for ACE, and 9 reported no preference. Compared with quiet, in noisy situations, there was a stronger preference for OPAL (19 recipients), a similar preference for ACE (7 recipients), while fewer expressed no preference. Average daily take-home use of ACE and OPAL was 4.9 and 7.1 hr, respectively. For Mandarin-speaking CI recipients, OPAL provided significant improvements to lexical tone perception for natural and normalized tones in quiet and noise, monosyllabic word recognition in quiet, and subjective ratings of speech intelligibility. Subjects accessed both primary and secondary cues to lexical tone for perception in quiet and noise conditions. The benefits of lexical tone recognition were attributed to enhanced F0 rate cues encoded by OPAL, especially in a noisy environment. The OPAL strategy was well accepted by many of the Mandarin-speaking CI recipients.

Modeling Lexical Tones for Speaker Discrimination.

Fundamental frequency (F0) has been widely studied and used in the context of speaker discrimination and forensic voice comparison casework, but most previous studies focused on long-term F0 statistics. Lexical tone, the linguistically structured and dynamic aspects of F0, has received much less research attention. A main methodological issue lies on how tonal F0 should be parameterized for the best speaker discrimination performance. This paper compares the speaker discriminatory performance of three approaches with lexical tone modeling: discrete cosine transform (DCT), polynomial curve fitting, and quantitative target approximation (qTA). Results show that using parameters based on DCT and polynomials led to similarly promising performance, whereas those based on qTA generally yielded relatively poor performance. Implications modeling surface tonal F0 and the underlying articulatory processes for speaker discrimination are discussed.

Multimodal cues in L2 lexical tone acquisition: current research and future directions

This review discusses the effectiveness of visual and haptic cues for second language (L2) lexical tone acquisition, with a special focus on observation and production of hand gestures. It explains how these cues can facilitate initial acquisition of L2 lexical tones via multimodal depictions of pitch. In doing so, it provides recommendations for incorporation of multimodal cues into L2 lexical tone pedagogy.

Perception of Mandarin tones across different phonological contexts by native and tone-naive listeners

Coarticulation is a type of speech variation where sounds take on phonetic properties of adjacent sounds. Listeners generally display perceptual compensation, attributing coarticulatory variation to its source. Mandarin Chinese lexical tones are coarticulated based on surrounding tones. We tested how L1-Mandarin and naive listeners compensate for tonal coarticulation using a paired discrimination task. L1 listeners showed greater perceptual sensitivity to tonal differences than tone-naive listeners. Yet, both L1 and tone-naive listeners showed differences in sensitivity to differently-coarticulated versions of the rising tone presented in the same tonal context. In different tonal contexts, both groups showed similar patterns of perceptual compensation for tonal coarticulation. Thus, although L1 and naive Mandarin listeners show different sensitivities to tonal variation, they display similar compensatory patterns for tonal coarticulation.

Sensory intelligence for extraction of abstract auditory rules from a speech sound stream in children with cochlear implants

ObjectiveSensory intelligence in the brain helps listeners automatically extract abstract auditory rules formed by invariant acoustic features from complex speech sound streams, presumably serving as the neural basis for speech comprehension. However, whether this intelligence is deficient in children with cochlear implants (CIs) remains unclear. MethodsMandarin Chinese monosyllables shared a flat lexical tone contour to form an abstract auditory rule but differed in other acoustic features to construct a complex speech sound stream. The abstract rule was occasionally violated by monosyllables with a rising or falling lexical tone. ResultsIn normal hearing (NH) children, the abstract auditory rule could be extracted, as revealed by a mismatch negativity (MMN) and a late discriminative negativity (LDN). However, the MMN and LDN were only evoked in CI children with good hearing and speech performance. NH children with a higher speech perception or spatial hearing score had a greater MMN. The LDN was attenuated with increasing age in NH children. ConclusionsThe sensory intelligence for extraction of auditory abstract rules, associated with speech perception, is deficient in CI children. This intelligence may gradually develop during childhood and adolescence. SignificanceDeficient sensory intelligence in CI children may aid in understanding poor speech comprehension in complex environments.

Crossmodal correspondence between lexical tones and visual motions: a forced-choice mapping task on Mandarin Chinese

Abstract Crossmodal correspondence refers to the phenomenon in which individuals match stimulus features (e.g., auditory pitch) with different sensory modalities (e.g., visual size). While studies on correspondences exhibited by suprasegmentals have mostly focused on pitch-size and pitch-shape associations, audiospatial binding observed in the production and perception of Mandarin tones, where pitch of the syllable distinguishes word meanings, sheds light on the symbolic potential of auditory pitch. In the present study, a forced-choice mapping task was conducted in the form of a word guessing game, where native Mandarin listeners select the meaning of an auditory “alien” word from two visual motions. The results showed that: (1) listeners reliably match auditory tones with visual motions in the way that pitch trajectories are congruent with spatial movements, (2) vowel category impacts tone-motion correspondence when syllables are articulated in non-contour tones, and (3) the capacities in driving the tone-motion correspondence are different across tonal categories. These findings further contribute to our understanding of the sound symbolic potential of lexical tones and expand the boundary of crossmodal correspondence that can be demonstrated by pitch.

Early auditory processing of speech in prelingually-deafened children with cochlear implants based on event-related potentials

Objective: To investigate the early auditory discrimination of vowels, consonants and lexical tones in prelingually-deafened children with cochlear implants (CI) using auditory event-related potentials. Methods: Nineteen prelingually-deafened CI children and 19 normal hearing (NH) children were recruited in this study. A multi-deviant oddball paradigm was constructed using the monosyllable/ta1/as the standard stimulus and monosyllables/tu1/,/te1/, /da1/,/ra1/,/ta4/and/ta2/as the deviant stimuli. The event-related potentials evoked by vowel, consonant and lexical tone contrasts were recorded and analyzed in the two groups. Results: NH children showed robust mismatch negativities (MMNs) to vowel, consonant and lexical tone contrasts (P<0.05), whereas CI children only showed positive mismatch responses (pMMRs) and P3a responses to the vowel (P<0.05) and consonant contrasts (P<0.05) and no significant event-related potential to the lexical tone contrasts (P>0.05). The longer pMMR and P3a peak latencies (P<0.01) but similar amplitudes (P>0.05) were found in CI children than in NH children. CI children showed weaker phase synchronization of θ oscillations than NH children (P<0.05). The duration of CI use was positively correlated with the scores of Categories of Auditory Performance (CAP) (P=0.004), Speech Intelligibility Rate (SIR) (P=0.044) and Meaningful Auditory Integration Scale (MAIS) (P=0.001) in CI children. Conclusions: Prelingually-deafened CI children can process vowels and consonants at an early stage. However, their ability of processing speech, especially lexical tones, is still more immature compared with their NH peers. The event-related potentials could be objective electrophysiological indicators reflecting the maturity of CI children's auditory speech functions. Long-term CI use is beneficial for prelingually-deafened children to improve auditory and speech performance.

An investigation of acoustic cues to tonal registers and voicing in Donglei Kama).

The Kam language has experienced historical tonal splits, resulting in the development of a complex tonal system. However, there is still limited knowledge regarding the acoustic characteristics associated with aspiration-based tone splitting. This study aims to investigate the acoustic cues related to the tonal registers and laryngeal configurations in Donglei Kam, a dialect of Southern Kam. Sixteen native speakers of Donglei Kam participated, producing lexical tones. Statistical analyses were conducted to examine the acoustic distinctions between tonal registers, using measurements of voice onset time, spectral tilt, noise, and energy. The results indicated that Donglei Kam retained a two-way contrast of aspiration, albeit with a trend toward gradual loss. Additionally, a breathy voice was detected in the Ciyin tonal register, characterized by elevated spectral tilt values and spectral noise throughout the vowels. Moreover, machine learning classifiers effectively identified tonal registers using voice-quality data, suggesting that the phonation contrast between breathy and modal voice could contribute to the tonal split alongside pitch contrast. In summary, these findings enhance our understanding of the acoustic implementation of breathiness in Kam and offer valuable insights into the role of laryngeal contrast in tonal splits.