Mandarin Lexical Tones Research Articles

Speech Production of Mandarin Lexical Tones Among Canadian Elementary Students Enrolled in Mandarin-English Bilingual Schools.

This study investigates how Mandarin-English bilingual students in Canada produce Mandarin tones and how this is influenced by factors such as tone complexity, cross-linguistic influences, and speech input. Participants were 82 students enrolled in a Chinese bilingual program in Western Canada. Students were recruited from Grades 1, 3, and 5 and divided into two groups based on their home language backgrounds: The heritage language group had early and strong input in Mandarin, and the second language (L2) group received mostly English input at home. Single-word tone productions were audio-recorded and transcribed by Mandarin-native listeners for match (accuracy) and pattern analyses. Acoustic measurements were extracted to provide phonetic details. First, Tone3 (dipping tone) was challenging across groups due to its complexity. Second, L2 students' productions were more influenced by English as a nontonal language and showed signs of categorical confusion. Third, increased tone match rates were related to both home input and school input, but bilingual students did not reach more than 90% of match rates in Grade 5. Instead, L2 students produced phonetic features less accurately in higher grades. This was attributed to reduced pronunciation instruction and limited home input. Bilingual students' speech development in a minority language indicates unique influences of home and school input but also the universal influences of tone complexity. This study provides evidence for bilingual speech theories in the suprasegmental domain and has implications for the pedagogy of a minority language in the context of bilingual education. https://doi.org/10.23641/asha.28098206.

Tone superimposition technique in Speech Sciences: a tutorial

In the literature, we encounter papers reporting manipulating pitch contours in speech tokens for a specific problem to be addressed in experiments (e.g., learning pitch patterns superimposed onto a pseudo-syllable), usually in the field of Speech Perception and Spoken Word Recognition. This type of research often tests listeners’ perceptual and processing skills in tonal languages (e.g., Mandarin, Thai, etc.), and requires superimposing a pitch contour onto a spoken syllable. However, very few studies reported in detail how this critical manipulation was done to meet specific experimental needs. In addition, there was neither specific guideline or description of the techniques being used, nor how ‘natural’ these manipulated tokens sounded in a particular language upon speech synthesis. Because this technique is crucial in establishing the conclusions in various studies, here, we will demonstrate our method of establishing this technique of tone superimposition (i.e., lexical tones in Mandarin) onto English syllables. In line with the open science model, we will also show our stimuli and procedures via OSF for readers to evaluate the validity of this technique. Manipulating the pitch contour in a spoken syllable can be complicated and change the perception of the spoken syllable in a significant way. Thus, we will also show the important factors to be considered in this process for doing research in Speech Sciences.

Neural oscillation to Mandarin lexical tone processing in bilingual children: A developmental study

Tonal language experience is associated with structural and functional characteristics in the brain that underlie facilitated pitch perception. However, it is less understood what the developmental trajectory is for lexical tone processing at the cortical level, especially in bilingual children. In the present research, we investigated these developmental changes in terms of neuronal oscillations in response to Mandarin lexical tone contrasts. We measured lexical tone processing in bilingual English-Mandarin learning children and bilingual English-Mandarin young adults. Event-related brain potentials (ERPs) were recorded in an oddball paradigm with two tonal contrasts: one with a small acoustical difference, and one with a larger acoustical difference. We then analyzed the phase locking and amplitude modulation of ongoing oscillations in theta (4–8 Hz), alpha (8–14 Hz), and beta (14–30 Hz) bands to two types of lexical tone changes. Preliminary results suggest developmental changes were associated with strengthened phase locking of neural oscillations to both small and large acoustical contrasts, while stronger phase locking and higher power was observed in the larger acoustical contrast. Beyond this, the theta, alpha, and beta bands demonstrated different sensitivities to developmental changes. Such findings further our understanding of bilingual lexical tone development at the cortical level.

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.

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.

The Effect of Visual Articulatory Cues on the Identification of Mandarin Tones by Children With Cochlear Implants.

This study explored the facilitatory effect of visual articulatory cues on the identification of Mandarin lexical tones by children with cochlear implants (CIs) in both quiet and noisy environments. It also explored whether early implantation is associated with better use of visual cues in tonal identification. Participants included 106 children with CIs and 100 normal-hearing (NH) controls. A tonal identification task was employed using a two-alternative forced-choice picture-pointing paradigm. Participants' tonal identification accuracies were compared between audio-only (AO) and audiovisual (AV) modalities. Correlations between implantation ages and visual benefits (accuracy differences between AO and AV modalities) were also examined. Children with CIs demonstrated an improved identification accuracy from AO to AV modalities in the noisy environment. Additionally, earlier implantation was significantly correlated with a greater visual benefit in noise. These findings indicated that children with CIs benefited from visual cues on tonal identification in noise, and early implantation enhanced the visual benefit. These results thus have practical implications on tonal perception interventions for Mandarin-speaking children with CIs.

Tonal identification in whispered speech

This project aims to examine whether, and how, non-F0 cues facilitate the identification of lexical tones. A perception experiment is designed to explicitly test the impact of duration cues for Mandarin lexical tones when F0 is absent. We take a novel approach in which the secondary cue of interest is held constant, effectively controlling the type of information listeners receive. Future studies can potentially extend this methodology to examine other relevant cues, such as temporal envelope and intensity. The contribution of this paper is twofold: first, to propose an explanation for the inconsistent conclusions drawn in the literature on tonal identification in whispered speech; second, to devise a more well-controlled study shedding light on the nature of tonal perception.

Clear speech effects in production of sentence-medial Mandarin lexical tonesa).

Adding to limited research on clear speech in tone languages, productions of Mandarin lexical tones were examined in pentasyllabic sentences. Fourteen participants read sentences imagining a hard-of-hearing addressee or a friend in a casual social setting. Tones produced in clear speech had longer duration, higher intensity, and larger F0 values. This style effect was rarely modulated by tone, preceding tonal context, or syllable position, consistent with an overall signal enhancement strategy. Possible evidence for tone enhancement was observed only in one set of analysis for F0 minimum and F0 range, contrasting tones with low targets and tones with high targets.

The role of phonology in non-native word learning: Evidence from cross-situational statistical learning

Abstract Adults often encounter difficulty perceiving and processing sounds of a second language (L2). In order to acquire word-meaning mappings, learners need to determine what the language-relevant phonological contrasts are in the language. In this study, we examined the influence of phonology on non-native word learning, determining whether the language-relevant phonological contrasts could be acquired by abstracting over multiple experiences, and whether awareness of these contrasts could be related to learning. We trained English- and Mandarin-native speakers with pseudowords via a cross-situational statistical learning task (CSL). Learners were able to acquire the phonological contrasts across multiple situations, but similar-sounding words (i.e., minimal pairs) were harder to acquire, and words that contrast in a non-native suprasegmental feature (i.e., Mandarin lexical tone) were even harder for English-speakers, even with extended exposure. Furthermore, awareness of the non-native phonology was not found to relate to learning.

Constraints on novel word learning in heritage speakers.

Recent research on word learning has found that adults can rapidly learn novel words by tracking cross-situational statistics, but learning is greatly influenced by the phonological properties of the words and by the native language of the speakers. Mandarin-native speakers could easily pick up novel words with Mandarin tones after a short exposure, but English-native speakers had specific difficulty with the tonal components. It is, however, unclear how much experience with Mandarin is needed to successfully use the tonal cue in word learning. In this study, we explored this question by focusing on the heritage language population, who typically are exposed to the target language at an early age but then develop and switch to another majority language. Specifically, we investigated whether heritage Mandarin speakers residing in an English-speaking region and speaking English as a dominant language would be able to learn novel Mandarin tonal words from statistical tracking. It helps us understand whether early exposure to the target feature is sufficient to promote the use of that feature in word learning later in life. We trained 30 heritage Mandarin speakers with Mandarin pseudowords via a cross-situational statistical word learning task (CSWL). Heritage Mandarin speakers were able to learn the pseudowords across multiple situations, but similar-sounding words (i.e., minimal pairs) were more difficult to identify, and words that contrast only in lexical tones (i.e., Mandarin lexical tone) were distinguished at chance level throughout learning. We also collected information about the participants' heritage language (HL) experience and usage. We did not observe a relationship between HL experience/usage and performance in tonal word learning, suggesting that HL exposure does not necessarily lead to an advantage in learning the target language.

Categorical Perception of Lexical Tones and Stops in Mandarin-Speaking Musicians and Nonmusicians

This study investigates the perception of Mandarin lexical tones and stops to examine the degree of overlap between music and language. Eighteen musicians and 21 nonmusicians participated in a typical categorical perception task. Results showed that musicians and nonmusicians had comparable degree of categorical perception of tones and stops. Compared to nonmusicians, musicians exhibited enhanced sensitivities to within-category lexical tone stimuli. However, this improved ability was not observed in the perception of stops. These findings imply that musical experience strengthens the acuity of subtle low-level acoustic variations between within-category lexical tone stimuli without interfering with the high-level phonological representations of lexical tones, and this facilitatory effect is selective and could not readily extend to stop consonants in native language.

A Study on the Production of Mandarin Lexical Tones and Disyllabic Sequences Containing the Third Tone by Intermediate-Level Chinese Learners from Laos

A Study on the Production of Mandarin Lexical Tones and Disyllabic Sequences Containing the Third Tone by Intermediate-Level Chinese Learners from Laos

Lexical tone as a cue in statistical word learning from bilingual input

Abstract Learners can track word-referent co-occurrences across individually-ambiguous naming events to form correct word-referent mappings, termed statistical word learning (SWL). Prior research largely focuses on learning from a single language input, where a referent co-occurs with a single word (1:1 mapping). Here, we tested adults’ SWL from a simulated bilingual environment, where one referent co-occurred with two words (2:1 mapping) and the two words were either differentiated by a linguistic cue (Mandarin lexical tones, Cued condition) or not (Uncued condition). Results showed that in the Cued condition, Chinese–English bilinguals (N = 38) outperformed Spanish–English bilinguals (N = 56) and English monolinguals (N = 55), while Spanish–English bilinguals and English monolinguals performed similarly. The three groups did not differ in the Uncued condition. Self-reported learning confidence and strategies showed limited conscious awareness of learning. Results demonstrate that familiarity with a linguistic cue boosts overall statistical word learning from bilingual input.

Primacy of mouth over eyes to perceive audiovisual Mandarin lexical tones.

The visual cues of lexical tones are more implicit and much less investigated than consonants and vowels, and it is still unclear what facial areas contribute to facial tones identification. This study investigated Chinese and English speakers' eye movements when they were asked to identify audiovisual Mandarin lexical tones. The Chinese and English speakers were presented with an audiovisual clip of Mandarin monosyllables (for instance, /ă/, /à/, /ĭ/, /ì/) and were asked to identify whether the syllables were a dipping tone (/ă/, / ĭ/) or a falling tone (/ à/, /ì/). These audiovisual syllables were presented in clear, noisy and silent (absence of audio signal) conditions. An eye-tracker recorded the participants' eye movements. Results showed that the participants gazed more at the mouth than the eyes. In addition, when acoustic conditions became adverse, both the Chinese and English speakers increased their gaze duration at the mouth rather than at the eyes. The findings suggested that the mouth is the primary area that listeners utilise in their perception of audiovisual lexical tones. The similar eye movements between the Chinese and English speakers imply that the mouth acts as a perceptual cue that provides articulatory information, as opposed to social and pragmatic information.

Cochlear implant pitch and lexical tone perception in quiet and noise using F0-rate coding

Fundamental frequency (F0) cues to voice/musical pitch can be coded by pulse-rate or amplitude modulation (AM) rate of electrical pulse-trains in cochlear implant (CI) systems. However, for most clinical strategies (e.g., ACE), temporal cues to F0 are often poorly coded, particularly for female and children's voices and/or in background noise. Strategies such as Optimized Pitch And Language (OPAL) and Fundamental Asynchronous Stimulus Timing (FAST) enhance temporal F0 cues. For OPAL, F0 is estimated and used to control the AM rate coded by electrical pulse-trains in channel containing harmonics of F0. Significant benefits of OPAL to pitch ranking, speech intonation, and Mandarin lexical tone recognition have been observed compared to ACE. For FAST, peak-timing information in channel envelopes is used to derive pulse-timing in each channel and therefore much lower stimulation rates are provided resulting in longer battery life. In bilateral CI systems, it provides better ITD sensitivity, lateralization, and spatial release from masking compared to ACE. Presented here are the results of two studies, the first explored pitch perception of harmonic tones presented in quiet and noise using experimental OPAL and FAST strategies, and the second examined Mandarin lexical tone perception in quiet and noise using ACE and OPAL in a clinical processor.

Cortical processing of Mandarin lexical tone in children with different language backgrounds

Bilingual experience modulates cognitive skills, particularly executive control. However, it is not clear if such modulation can be observed in automatic speech processing. Furthermore, it is unknown if bi-dialectal experience will enhance speech processing. This study aims to investigate whether and how early bilingual experience influences cortical sensitivity for automatic cortical processing of speech, specifically in the context of tonal and non-tonal languages. A passive listening oddball paradigm with two lexical tone contrasts were used and event-related potentials were recorded. An easy contrast (tone 1 versus tone 3) and a hard contrast (tone 2 versus tone 3) were used as the stimuli. Children between 5 and 10 years of age were tested. Preliminary results indicate that monolingual mainstream English, African-American English, and bilingual Mandarin-English learners all showed similar brain responses to the easy lexical tone contrast. However, there was an age effect across language groups. Such results suggest that biological factors such as age are stronger predictors of brain responses to lexical tone contrasts comparing to the factor of language background.

Categorization and discrimination of Mandarin lexical tones by naïve English listeners

Unlike tone languages such as Mandarin, English lacks tones at the sub-lexical level. Accordingly, English listeners have difficulty perceptually assimilating tones as categorized or uncategorized native segments (Perceptual Assimilation Model, PAM: Best, 1995). While English listeners can categorize the four lexical tones of Mandarin, i.e., level contour, rising, dipping, and falling, when given question, statement, exclamation, and uncertainty intonations as category choices (So & Best, 2011, 2014), this does not address tone assimilation at the segmental level. We reasoned that they might assimilate tones as non-assimilable nonspeech patterns if given visual icons as tone category choices (flat, rising, dipping, and falling lines, respectively), with no reference being made to English intonation categories. Accordingly, 76 monolingual English listeners (M age = 24.85 years, 50 females) were set two tasks: to use visual icons to categorize Mandarin tones in naturally produced tone-words (/ga, ti, tu, pu/ × 4 tones) and to discriminate all six pairwise tone contrasts. All tone pairs showed ceiling-level discrimination, and listeners split their categorizations of falling and level stimuli between the falling and flat icons, suggesting that when given visual icons, tone-naïve English listeners perceive Mandarin tones as nonspeech acoustic patterns, which is consistent with PAM’s non-assimilation predictions.

Analysis of errors in Mandarin disyllabic tones produced by Vietnamese speakers

Abstract This study investigates the tone production of Mandarin disyllabic words by Vietnamese speakers. It aims to provide insights into the challenges Vietnamese speakers face when producing Mandarin tones in disyllabic words. In the study, there were 30 Vietnamese L2 learners of Mandarin, who were requested to produce 80 (4 tones × 4 tones × 5 words of each tonal combination) disyllabic words in Mandarin. The overall results showed that Tone 4 was the most difficult among the four lexical tones. In the first syllable, most errors were found for Tone 3 when followed by another Tone 3 (where the first Tone 3 should be pronounced as a rising tone, similar to Tone 2, but mispronounced as Tone 3), which indicated that Vietnamese speakers tend to underapply Mandarin third tone sandhi. In the second syllable, most errors were found for Tone 4 when preceded by Tone 4 (the second Tone 4 mispronounced as Tone 1). The findings can help explore how L2 production models can account for L2 production of Mandarin tones by considering effects of phonetic/phonological nature of Mandarin lexical tones as well as the interference arising from the L1 phonology of learners.

Development of Mandarin Lexical Tone Identification in Noise and Its Relation With Working Memory.

This study aimed to examine the developmental trajectory of Mandarin tone identification in quiet and two noisy conditions: speech-shaped noise (SSN) and multitalker babble noise. In addition, we evaluated the relationship between tonal identification development and working memory capacity. Ninety-three typically developing children aged 5-8 years and 23 young adults completed categorical identification of two tonal continua (Tone 1-4 and Tone 2-3) in quiet, SSN, and babble noise. Their working memory was additionally measured using auditory digit span tests. Correlation analyses between digit span scores and boundary widths were performed. Six-year-old children have achieved the adultlike ability of categorical identification of Tone 1-4 continuum under both types of noise. Moreover, 6-year-old children could identify Tone 2-3 continuum as well as adults in SSN. Nonetheless, the child participants, even 8-year-olds, performed worse when tokens from Tone 2-3 continuum were masked by babble noise. Greater working memory capacity was associated with better tone identification in noise for preschoolers aged 5-6 years; however, for school-age children aged 7-8 years, such correlation only existed in Tone 2-3 continuum in SSN. Lexical tone perception might take a prolonged time to achieve adultlike competence in babble noise relative to SSN. Moreover, a significant interaction between masking type and stimulus difficulty was found, as indicated by Tone 2-3 being more susceptible to interference from babble noise than Tone 1-4. Furthermore, correlations between working memory capacity and tone perception in noise varied with developmental stage, stimulus difficulty, and masking type.

Bilateral human laryngeal motor cortex in perceptual decision of lexical tone and voicing of consonant

Speech perception is believed to recruit the left motor cortex. However, the exact role of the laryngeal subregion and its right counterpart in speech perception, as well as their temporal patterns of involvement remain unclear. To address these questions, we conducted a hypothesis-driven study, utilizing transcranial magnetic stimulation on the left or right dorsal laryngeal motor cortex (dLMC) when participants performed perceptual decision on Mandarin lexical tone or consonant (voicing contrast) presented with or without noise. We used psychometric function and hierarchical drift-diffusion model to disentangle perceptual sensitivity and dynamic decision-making parameters. Results showed that bilateral dLMCs were engaged with effector specificity, and this engagement was left-lateralized with right upregulation in noise. Furthermore, the dLMC contributed to various decision stages depending on the hemisphere and task difficulty. These findings substantially advance our understanding of the hemispherical lateralization and temporal dynamics of bilateral dLMC in sensorimotor integration during speech perceptual decision-making.