High-falling Tone Research Articles

Distributional learning of non-native tone contrasts by older adults after training and overnight consolidation

Despite decline in psychoacoustic and statistical learning (SL) abilities, older adults demonstrate remarkably intact perceptual learning in both L2 (tone-word learning) and L1 settings (perceptual adaptation to accented/noise-vocoded speech) but show limited transfer of learning to untrained stimuli. This study tests whether perceptual learning is maintained in an implicit statistical learning task where older adults learn L2 tonal contrasts through exposure to probability distributions of tonal tokens, which may pose higher requirements on both psychoacoustic and SL abilities, and whether sleep-dependent consolidation helps the generalization of perceptual knowledge. L1-Cantonese older adults learned to discriminate a perceptually difficult level-falling tone contrast following a pre-test, training, post- training overnight interval. Training stimuli were synthesized by interpolating naturally produced Mandarin level and high-falling tones into six equidistant steps. Participants either heard a bimodal (two-peak resembling level-falling categories) or unimodal distribution (single-peak) consisting of 256 tokens. ABX discrimination task was administered for testing, with tokens by two genders and on two pseudo-syllables to test generalization. Pilot data of 14 participants showed a trend of group effect with the bimodal group outperforming the unimodal group after training and sleep-dependent consolidation, showing that perceptual learning is maintained in a paradigm that relies heavily on psychoacoustic and SL abilities.

Cricothyroid Dysfunction in Unilateral Vocal Fold Paralysis Females Impairs Lexical Tone Production.

In this cross-sectional study, we compared voice tone and activities relating to the laryngeal muscle between unilateral vocal fold paralysis (UVFP) patients with and without cricothyroid (CT) muscle dysfunction to define how CT dysfunction affects language tone. Eighty-eight female surgery-related UVFP patients were recruited and received acoustic voice analysis and laryngeal electromyography (LEMG) when the patient was producing the four Mandarin tones. The statistical analysis was compared between UVFP patients with (CT+ group, 17 patients) and without CT muscle (CT- group, 71 patients) involvement. When producing Mandarin Tone 2, the voice tone in the CT+ group had smaller rise range (p = 0.007), lower rise rate (p = 0.002), and lower fundamental frequency (F0) at the offset point of the voice (p = 0.023). When producing Mandarin Tone 4, the voice tone in the CT+ group had smaller drop range (p = 0.019), lower drop rate (p = 0.005), and lower F0 at voice onset (p = 0.025). The CT+ group had significantly lower CT muscle activity when producing the four Mandarin tones. In conclusion, CT dysfunction causes a limitation of high-rising tone in Tone 2 and high-falling tone in Tone 4, a property that dramatically limits the tonal characteristics in Mandarin, a tonal language. This limitation could further impair the patient's communication ability.

Influence of clear speech on F0 patterns of Mandarin lexical tones

When communication becomes difficult, a talker may take on a form of communication known as clear speech (Keerstock & Smilijanic, 2019; Picheny et al., 1985). Little is known, however, about clear-speech modifications in tone languages (Zeng, 2017). This study showed how native Mandarin speakers modulate F 0 in tone words through increased variation, raised F 0 onset and offset. Participants read twenty-four sentences varied in four target tones, three times. Sentences were presented in two blocks: casual speech condition (as if talking to friends) and clear speech condition (as if communicating to someone with hearing loss). Data analysis of seven speakers suggested that effects of clear speech on F 0 contours were tone-dependent. As compared with casual speech, in clear speech, F 0 contours of high level (T1), mid-rising (T2), and high-falling (T4) tones were higher within the same tonal context; in contrast, F 0 contours of the low-dipping tone (T3) were lower preceding T1 and T4. F 0 range, onset F 0, and offset F 0 were greater in clear speech mode across most tonal environments. Additional data of eleven speakers has been collected to examine preliminary results and discuss findings in terms of signal-enhancement in clear speech production of lexical tones.

Deficits in Processing of Lexical Tones in Mandarin-Speaking Children With Developmental Language Disorder: Electrophysiological Evidence.

Purpose This study explored the neural marker indexing deficits in discriminating lexical tone changes in Mandarin-speaking children with developmental language disorders (DLDs) using mismatch negativity, an event-related potential component for auditory change detection. Mandarin has four lexical tones characterized by a high-level tone (T1), high-rising tone (T2), low-dipping tone (T3), and high-falling tone (T4), in which the T2/T3 contrast is acoustically less discriminable in developmental groups. Therefore, this study further examined how deficits in children with DLD would vary with tonal contrasts' acoustic saliency. Method Event-related potentials were measured using the multideviant oddball paradigm described by Lee et al. (2012), who used Mandarin syllables [i] in T3 as the standard sound (80%), T1 as the large deviant (10%), and T2 as the small deviant (10%). Twelve children with DLD aged between 4 and 6 years participated in this study, and 12 age-matched children with typical development were selected from the data set of Lee et al. (2012) as the controls. Results The T1/T3 change elicited adultlike mismatch negativity in both the DLD and control groups, while no group difference was revealed. The T2/T3 change elicited a robust positive mismatch response (P-MMR) in children with DLD, while the P-MMR was less significant in the control group. The group comparisons revealed a larger P-MMR in children with DLD than in the control group. Furthermore, children with lower scores in language assessments tend to reveal larger P-MMRs. Conclusions This study demonstrated that deficits in children with DLD in discriminating subtle lexical tone changes reflect greater positivity of P-MMR to T2/T3 change. This implies that MMR to T2/T3 may serve as a neural marker for evaluating language delay in preschoolers.

Relative Contribution of Auditory and Visual Information to Mandarin Chinese Tone Identification by Native and Tone-naïve Listeners.

Speech perception is a multisensory process: what we hear can be affected by what we see. For instance, the McGurk effect occurs when auditory speech is presented in synchrony with discrepant visual information. A large number of studies have targeted the McGurk effect at the segmental level of speech (mainly consonant perception), which tends to be visually salient (lip-reading based), while the present study aims to extend the existing body of literature to the suprasegmental level, that is, investigating a McGurk effect for the identification of tones in Mandarin Chinese. Previous studies have shown that visual information does play a role in Chinese tone perception, and that the different tones correlate with variable movements of the head and neck. We constructed various tone combinations of congruent and incongruent auditory-visual materials (10 syllables with 16 tone combinations each) and presented them to native speakers of Mandarin Chinese and speakers of tone-naïve languages. In line with our previous work, we found that tone identification varies with individual tones, with tone 3 (the low-dipping tone) being the easiest one to identify, whereas tone 4 (the high-falling tone) was the most difficult one. We found that both groups of participants mainly relied on auditory input (instead of visual input), and that the auditory reliance for Chinese subjects was even stronger. The results did not show evidence for auditory-visual integration among native participants, while visual information is helpful for tone-naïve participants. However, even for this group, visual information only marginally increases the accuracy in the tone identification task, and this increase depends on the tone in question.

Mandarin Tone Identification by Tone-Naïve Musicians and Non-musicians in Auditory-Visual and Auditory-Only Conditions

A considerable number of studies have shown that musical ability has a positive effect on language processing. Extending this body of work, this study investigates the effects of musicality and modality on Mandarin tone identification in tone-naive participants. To examine the effects of visual information in speech, Mandarin tones were presented in auditory-only or auditory-visual modalities to participants with or without musical experience. The Goldsmith Musicality Index was used to assess the musical aptitude of the participants. Overall, musicians outperformed non-musicians in the tone identification task in both auditory-visual and auditory-only conditions. Both groups identified tones more accurately in the auditory-visual condition than in the auditory-only condition. In addition, performance differed by tone: musicality holds its main effect on each level of tone; while the influence of modality differs for individual tones; the identification of tone 3 (a low-falling-rising) proved to be the easiest, while tone 4 (a high-falling tone) was the most difficult to identify for all participants. Out of all the musical skills measured by the Goldsmith Musicality Index, the amount of musical training was the only predictor that had an impact on the accuracy of Mandarin tone perception. These findings suggest that learning to perceive Mandarin tones benefits from musical expertise, and visual information can facilitate Mandarin tone identification, but mainly for tone-naive non-musicians.

One Way or Another: Evidence for Perceptual Asymmetry in Pre-attentive Learning of Non-native Contrasts.

Research investigating listeners’ neural sensitivity to speech sounds has largely focused on segmental features. We examined Australian English listeners’ perception and learning of a supra-segmental feature, pitch direction in a non-native tonal contrast, using a passive oddball paradigm and electroencephalography. The stimuli were two contours generated from naturally produced high-level and high-falling tones in Mandarin Chinese, differing only in pitch direction (Liu and Kager, 2014). While both contours had similar pitch onsets, the pitch offset of the falling contour was lower than that of the level one. The contrast was presented in two orientations (standard and deviant reversed) and tested in two blocks with the order of block presentation counterbalanced. Mismatch negativity (MMN) responses showed that listeners discriminated the non-native tonal contrast only in the second block, reflecting indications of learning through exposure during the first block. In addition, listeners showed a later MMN peak for their second block of test relative to listeners who did the same block first, suggesting linguistic (as opposed to acoustic) processing or a misapplication of perceptual strategies from the first to the second block. The results also showed a perceptual asymmetry for change in pitch direction: listeners who encountered a falling tone deviant in the first block had larger frontal MMN amplitudes than listeners who encountered a level tone deviant in the first block. The implications of our findings for second language speech and the developmental trajectory for tone perception are discussed.

The effects of prosody on pitch and voice quality of White Hmong tones

White Hmong contrasts two high-falling tones (one breathy, the other modal) and two low tones (one modal level-tone, the other creaky low-falling). Perceptual studies [Garellek et al. (2013)] have shown that listeners rely on breathy voice to distinguish between the high-falling tones, but ignore creaky voice when distinguishing between the low tones. We test whether such differences stem from prosodic variation, by examining tokens from stories read by native speakers. Vowels were annotated for phrasal position and neighbouring tones. We obtained f0 and voice quality measures. Results support and help elucidate previous perceptual research: (1) the breathy high-falling tone is breathy in all prosodic positions, (2) the breathy high-falling tone has a prosodically-variable f0, (3) the creaky low-falling tone has a prosodically-stable f0. The creaky low-falling tone is creakier than the modal low tone in all positions. Therefore, listeners may ignore f0 in the identification of the breathy high-falling ton...

Statistical learning of speech sounds is most robust during the period of perceptual attunement

Although statistical learning has been shown to be a domain-general mechanism, its constraints, such as its interactions with perceptual development, are less well understood and discussed. This study is among the first to investigate the distributional learning of lexical pitch in non-tone-language-learning infants, exploring its interaction with language-specific perceptual attunement during the first 2years after birth. A total of 88 normally developing Dutch infants of 5, 11, and 14months were tested via a distributional learning paradigm and were familiarized on a unimodal or bimodal distribution of high-level versus high-falling tones in Mandarin Chinese. After familiarization, they were tested on a tonal contrast that shared equal distributional information in either modality. At 5months, infants in both conditions discriminated the contrast, whereas 11-month-olds showed discrimination only in the bimodal condition. By 14months, infants failed to discriminate the contrast in either condition. Results indicate interplay between infants' long-term linguistic experience throughout development and short-term distributional learning during the experiment, and they suggest that the influence of tonal distributional learning varies along the perceptual attunement trajectory, such that opportunities for distributional learning effects appear to be constrained in the beginning and at the end of perceptual attunement. The current study contributes to previous research by demonstrating an effect of age on learning from distributional cues.

Development and evaluation of wheel-controlled pitch-adjustable electrolarynx

Tone is important in tonal languages, especially in Mandarin. However, there is presently no commercially available electrolarynx (EL) for laryngectomized Mandarin speakers. Moreover, few studies have focused on this area. Our purpose is to design an EL that produces the four Mandarin tones and to evaluate its performance. We designed a wheel-controlled pitch-adjustable EL and manufactured a prototype (Wheel-EL). Using monosyllables, disyllabic segments, and frequently used phrases, we evaluated speech produced by Wheel-EL and by monotone (M-TruTone) and variable-frequency modes (V-TruTone) of the commercially available TruTone EL. The pitch contours of the high-level (HL), middle-rising (MR), and falling-rising (FR) tones produced by Wheel-EL most closely matched the natural speech characteristics of a native speaker. However, redundant sounds were generated in the high-falling (HF) tone. The statistical accuracy of Wheel-EL's tone and word perception was significantly higher than that of other EL types. However, no significant differences existed in acceptability among the three EL speech types. Wheel-EL produces better HL, MR, and FR tones in Mandarin than either M-TruTone or V-TruTone. Nevertheless, redundant sounds affect HF phonation. Accurate tone judgment can improve the intelligibility of EL speech in Mandarin but has no obvious effect on acceptability.

An acoustic study of contextual tonal variation in Tianjin Mandarin

The f0 realization of lexical tones is known to vary greatly due to contextual tonal variation processes such as tone sandhi and tonal coarticulation. This study set out to investigate the f0 variability induced by these two different sources with well-controlled acoustic data from Tianjin Mandarin. Tianjin Mandarin is known for its complex patterns of tonal variation over disyllabic constituents, as well as for the conflicting directionality of sandhi alternations and possible iterative application of disyllabic sandhi rules over trisyllabic constituents. Previous studies on Tianjin tone sandhi have often been based on impressionistic descriptions of speech produced by speakers of older generations. In this study, we investigated the f0 realization of disyllabic and trisyllabic tonal sequences in Tianjin Mandarin produced by younger speakers (born in the 1980s). Through examining f0 variation of lexical tones as a function of different following tones, we observed an interesting anticipatory raising effect of the lexical low-falling tone (T1). Furthermore, we confirmed three tonal sequences with tone sandhi changes: (1) two low-falling tones (T1T1), (2) a high-falling tone followed by a low-falling tone (T4T1), and (3) two low-dipping tones (T3T3). These disyllabic tone sandhi patterns, however, were not consistently observed within trisyllabic sequences, as claimed in the literature. Specifically, while T3T3 showed sandhi application regardless of its position within a trisyllabic sequence, T1T1 and T4T1 sequences showed sandhi changes only when they were right aligned. Last but not least, no tonal neutralization was observed over any of the sandhi processes. Rather, we argue that T3T3 is a near-merger sandhi case, while T1T1 and T4T1 can be classified as no-merger sandhi sequences.

COMMUNICATIVE FOCUS ON FORM AND SECOND LANGUAGE SUPRASEGMENTAL LEARNING

The current study examined how form-focused instruction (FFI) with and without corrective feedback (CF) as output enhancement facilitated second language (L2) perception of Mandarin tones at both the phonetic and phonological levels by 41 Cantonese learners of Mandarin. Two experimental groups, FFI only and FFI-CF, received a 90-min FFI treatment designed to encourage them to notice and practice the categorical distinctions of Mandarin tones through a range of communicative input and output activities. During these activities, the instructors provided CF only to students in the FFI-CF group by recasting and pushing them to repair their mispronunciations of the target features (i.e., output enhancement). The control group received comparable meaning-oriented instruction without any FFI. The effectiveness of FFI was assessed via a forced-choice identification task with both trained and untrained items for a variety of tonal contrasts in Mandarin (high-level Tone 1 vs. mid-rising Tone 2 vs. high-falling Tone 4). According to statistical comparisons, the FFI-only group attained significant improvement in all lexical and tonal contexts, and such effectiveness was evident particularly in the acquisition of Tone 1 and Tone 4—supposedly the most difficult instances due to their identical phonological status in the learners’ first language, Cantonese. The FFI-CF group, however, demonstrated marginally significant gains only under the trained lexical conditions. The results suggest that FFI promotes learners’ attentional shift from vocabulary to sound learning (generalizable gains in trained and untrained items) and facilitates their access to new phonetic and phonological categories. Yet the relative advantage of adding CF to FFI as output enhancement remains unclear, especially with respect to the less experienced L2 learners in the current study.

PHONETIC INFLUENCES ON ENGLISH AND FRENCH LISTENERS’ ASSIMILATION OF MANDARIN TONES TO NATIVE PROSODIC CATEGORIES

This study examined how native speakers of Australian English and French, nontone languages with different lexical stress properties, perceived Mandarin tones in a sentence environment according to their native sentence intonation categories (i-Categories) in connected speech. Results showed that both English and French speakers categorized Mandarin tones primarily on the phonetic similarities of the pitch contours between the Mandarin tones and their native i-Categories. Moreover, French but not English speakers were able to detect the fine-detailed phonetic differences between Tone 3 (T3) and Tone 4 (T4; i.e., low or low-falling tone vs. high-falling tone), which suggests that the stress differences between these languages may affect nonnative tone perception: English uses lexical stress, whereas French does not. In the discrimination task, the French listeners’ performance was better than that of the English listeners. For each group, discrimination of the Tone 1 (T1)–T4 and Tone 2 (T2)–T3 pairs was consistently and significantly lower than that of the other tone pairs, and the difference between T1-T4 and T2-T3 was significant. Discrimination of the Mandarin tone pairs was not fully predicted by pairwise categorizations to native i-Categories, however. Some discrimination differences were observed among tone pairs showing the same assimilation patterns. Phonetic overlaps in native i-Category choices for the Mandarin tones, strength of categorization (So, 2012), and tonal coarticulation effects (Xu, 1994, 1997) may offer possible accounts of these discrepancies between categorization and discrimination performance. These findings support the perceptual assimilation model for suprasegmentals (So & Best, 2008, 2010a, 2010b, 2011, 2013), extended to categorization of nonnative tone words within sentence contexts to native i-Categories.

Impaired categorical perception of lexical tones in Mandarin-speaking congenital amusics

The degree to which cognitive resources are shared in the processing of musical pitch and lexical tones remains uncertain. Testing Mandarin amusics on their categorical perception of Mandarin lexical tones may provide insight into this issue. In the present study, a group of 15 amusic Mandarin speakers identified and discriminated Mandarin tones presented as continua in separate blocks. The tonal continua employed were from a high-level tone to a mid-rising tone and from a high-level tone to a high-falling tone. The two tonal continua were made in the contexts of natural speech and of nonlinguistic analogues. In contrast to the controls, the participants with amusia showed no improvement for discrimination pairs that crossed the classification boundary for either speech or nonlinguistic analogues, indicating a lack of categorical perception. The lack of categorical perception of Mandarin tones in the amusic group shows that the pitch deficits in amusics may be domain-general, and this suggests that the processing of musical pitch and lexical tones may share certain cognitive resources and/or processes (Patel 2003, 2008, 2012).

Categorizing Mandarin tones into listeners’ native prosodic categories: The role of phonetic properties

This study examined whether native speakers of non-tone languages (Australian English, and French) were able to perceive foreign Mandarin tones in a sentence environment according to their native prosodic categories. Results found that both English and French speakers were able to perceptually categorize foreign tones into their intonational categories (i-Categories), and that categorizations were based on the contextual phonetic similarities of the pitch contours they perceived between Mandarin tones and their native i-Categories. Results also showed that French speakers, but not English speakers, were able to detect the fine-detailed phonetic feature differences between Tone 3 and Tone 4 (low/falling tone vs. high-falling tone). The findings support a new extension of the Perceptual Assimilation Model (PAM; Best 1995) to suprasegmental phonology (So and Best 2008): that non-native prosodic categories (e.g. lexical tones) will be assimilated to the categories of listeners’ native prosodic system (e.g. intonation). In addition, rhythmic differences among languages may also contribute to perception of non-native tones.

The Effect of Tonal Changes on Voice Onset Time in Mandarin Esophageal Speech

The present study investigated the effect of tonal changes on voice onset time (VOT) between normal laryngeal (NL) and superior esophageal (SE) speakers of Mandarin Chinese. VOT values were measured from the syllables /pha/, /tha/, and /kha/ produced at four tone levels by eight NL and seven SE speakers who were native speakers of Mandarin. Results indicated that Mandarin tones were associated with significantly different VOT values for NL speakers, in which high-falling tone was associated with significantly shorter VOT values than mid-rising tone and falling-rising tone. Regarding speaker group, SE speakers showed significantly shorter VOT values than NL speakers across all tone levels. This may be related to their use of pharyngoesophageal (PE) segment as another sound source. SE speakers appear to take a shorter time to start PE segment vibration compared to NL speakers using the vocal folds for vibration.

Tonal Perceptions in Normal Laryngeal, Esophageal, and Electrolaryngeal Speech of Mandarin

The present study attempted to investigate if alaryngeal speakers of Mandarin Chinese could differentially produce the four tone levels of Mandarin: high-level, mid-rising, falling-rising and high-falling, as perceived by native listeners. Syllables /ma/ and /ba/ produced at four different tone levels by 8 normal laryngeal (NL), 7 standard esophageal (SE), and 8 electrolaryngeal (EL) speakers of Mandarin were perceived by 8 naïve listeners. Results from the listening experiments showed a higher percent correct identification of tone for NL speech than SE and EL speech. Perceptual data showed different patterns of tone confusion associated with the three types of speech. SE and EL speakers were not able to produce the four tone levels as accurately as were NL speakers. NL speakers achieved a near-perfect level of accuracy in signaling tonal contrasts. SE speakers produced the falling-rising and high-falling tones more accurately than high-level and mid-rising tones, but tonal confusions existed between mid-rising tone and falling-rising tone, and between high-level tone and high-falling tone. In EL phonation, high-level tone was produced more accurately than the other tones which were often misidentified as a high-level tone.

The role of final position in infants' identification of words in speech

Although statistical learning has been shown to be a domain-general mechanism, its constraints, such as its interactions with perceptual development, are less well understood and discussed. This study is among the first to investigate the distributional learning of lexical pitch in non-tone-language-learning infants, exploring its interaction with language-specific perceptual attunement during the first 2 years after birth. A total of 88 normally developing Dutch infants of 5, 11, and 14 months were tested via a distributional learning paradigm and were familiarized on a unimodal or bimodal distribution of high-level versus high-falling tones in Mandarin Chinese. After familiarization, they were tested on a tonal contrast that shared equal distributional information in either modality. At 5 months, infants in both conditions discriminated the contrast, whereas 11-month-olds showed discrimination only in the bimodal condition. By 14 months, infants failed to discriminate the contrast in either condition. Results indicate interplay between infants' long-term linguistic experience throughout development and short-term distributional learning during the experiment, and they suggest that the influence of tonal distributional learning varies along the perceptual attunement trajectory, such that opportunities for distributional learning effects appear to be constrained in the beginning and at the end of perceptual attunement. The current study contributes to previous research by demonstrating an effect of age on learning from distributional cues.

Effects of prosodic context on Taiwanese tones

Duration and F0 patterns for the high and high-falling tones of Taiwanese Amoy in different contexts were investigated in two experiments. The first examined the target tones in four prosodic positions: initial, medial, and final to a prosodic phrase, and utterance final. The nonutterance-final targets also varied in tonal context, being followed by high or mid tone. Words at the end of a prosodic phrase were substantially longer than in the other prosodic positions. The target tones were higher in frequency phrase-initially and phrase-medially than phrase- or utterance-finally. Tonal coarticulation occurred between the target tone and its following tone. When followed by high tone, the offset of the high target tone did not change, while that of the high-falling target tone increased. The second experiment investigated tonal coarticulation further by examining the high tone followed by five different tones in the middle and the end of a prosodic phrase. It is predicted that the tone height and the tone pattern of the target tone will vary depending on the following tone.

Duration and intensity as correlates of F0

The experiment reported in this paper is to determine whether fundamental frequency is correlated with both duration and intensity. Taiwanese was chosen for investigation as it has five contrastive tones, which are high, mid, low, high-falling and low-rising. A PDP-12 computer was used to obtain values of fundamental frequency, duration and intensity. The results show that (1) the high tone has a higher overall intensity than the mid tone, and the mid tone has a higher overall intensity than the low tone; (2) the high tone and the mid tone have a longer duration than the low tone, however, the difference in duration between the high tone and the mid tone is non-significant; (3) the high-falling tone has a higher overall intensity than the low-rising tone, although the low-rising tone has a longer duration. The results are discussed in terms of theories of pitch production and speed of pitch change.