Pitch Contour Research Articles

The interaction between phonological information and pitch type at pre-attentive stage: an ERP study of lexical tones

ABSTRACTPrevious studies on the processing of lexical tones have typically confounded effects due to phonological information (different meanings of words signalled by syllables with different tonal categories) with effects due to specific acoustic information (pitch type: pitch height/pitch contour). The present study is designed to dissociate these two kinds of effects and further investigate the processing of lexical tones at pre-attentive stage by mismatch negativity (MMN). We chose level tones and contour tones in Cantonese to differentiate pitch height from pitch contour, and manipulated tonal category (within-category/across-category) to distinguish phonological information from acoustic information. The results showed clear interactions between tonal category and pitch type in MMN mean amplitude and peak latency, suggesting the interaction between phonological information and pitch type in the pre-attentive processing of lexical tones. These results are discussed in light of cognitive and neural mechanisms underlying auditory processing of lexical tones.

Quantitative intonation modeling of interrogative sentences for Mandarin speech synthesis

Previous intonational research on Mandarin has mainly focused on the prosody modeling of statements or the prosody analysis of interrogative sentences. To support related speech technologies, e.g., Text-to-Speech, the quantitative modeling of intonation of interrogative sentences with a large-scale corpus still deserves attention. This paper summarizes our work on the quantitative prosody modeling of interrogative sentence in Mandarin. A large-scale natural speech corpus was used in this study. By extracting the pitch contours and fitting the intonation curves, we found that F0 declination and final lowering both existed in interrogative sentences, while they were claimed to be absent in Mandarin in some previous studies. In addition, the declination function could be modeled linearly, and the bearing unit of final lowering in Mandarin was found to be the last prosodic word in the utterance, regardless of its length, rather than a fixed duration range. It was argued in this study that the difference between this finding and the commonly believed rising intonation of the interrogative sentences resulted from the nonlinear relationship between prosody production and perception. The underlying mechanism for the existence of F0 declination and final lowering in interrogative sentences is also discussed.

The Effect of Focus and Phrase Position on East Norwegian Lexical Tonal Accents

Two experiments examined the acoustic correlates of the disyllabic tonal accent contrast in the Trøndersk dialect of Norwegian, and how narrow focus and phrasal position shape the contrast. Production results showed that both tonal accents have a high-low (HL) pitch contour, with different timing. In narrow focus, the pitch contrast was enlarged through asymmetrical F0 changes. When at the right edge of an accent phrase (AP), the accents were shown to have a higher L, lower AP H% tone, shorter stressed vowel, and longer final vowel. The alignment changes reflected tonal crowding while segmental modifications were due to the phrase-final lengthening in AP-final position. This work contributes to the literature on prosodic typology as well as on the implementation of prosodic focus and sentence intonation in languages with lexical pitch contrasts.

Pitch Perception in the First Year of Life, a Comparison of Lexical Tones and Musical Pitch.

Pitch variation is pervasive in speech, regardless of the language to which infants are exposed. Lexical tone is influenced by general sensitivity to pitch. We examined whether the development in lexical tone perception may develop in parallel with perception of pitch in other cognitive domains namely music. Using a visual fixation paradigm, 100 and one 4- and 12-month-old Dutch infants were tested on their discrimination of Chinese rising and dipping lexical tones as well as comparable three-note musical pitch contours. The 4-month-old infants failed to show a discrimination effect in either condition, whereas the 12-month-old infants succeeded in both conditions. These results suggest that lexical tone perception may reflect and relate to general pitch perception abilities, which may serve as a basis for developing more complex language and musical skills.

Aging Effect on Categorical Perception of Mandarin Tones 2 and 3 and Thresholds of Pitch Contour Discrimination.

The purpose of the study was to examine the aging effect on the categorical perception of Mandarin Chinese Tone 2 (rising F0 pitch contour) and Tone 3 (falling-then-rising F0 pitch contour) as well as on the thresholds of pitch contour discrimination. Three experiments of Mandarin tone perception were conducted for younger and older listeners with Mandarin Chinese as the native language. The first 2 experiments were in the categorical perception paradigm: tone identification and tone discrimination for a series of stimuli, the F0 contour of which systematically varied from Tone 2 to Tone 3. In the third experiment, the just-noticeable differences of pitch contour discrimination were measured for both groups. In the measures of categorical perception, older listeners showed significantly shallower slopes in the tone identification function and significantly smaller peakedness in the tone discrimination function compared with younger listeners. Moreover, the thresholds of pitch contour discrimination were significantly higher for older listeners than for younger listeners. These results suggest that aging reduced the categoricality of Mandarin tone perception and worsened the psychoacoustic capacity to discriminate pitch contour changes, thereby possibly leading to older listeners' difficulty in identifying Tones 2 and 3.

Mediant Mixture and “Blue Notes” in Rock

Rock features extensive use of mediant mixture, that is, the use of both scale-degrees3̂and ♭3̂within a song; it also has been said to employ “blue notes” that fall between these two degrees. In this study we explore these issues, seeking to gain a better understanding of the use of mediant mixture and blue notes in rock. In addition to conventional aural analysis, we use an automatic pitch-tracking algorithm that identifies pitch contours with high accuracy. We focus on the Jackson 5’s “ABC”; several other songs and sections of songs are also considered briefly. Our tentative conclusions are that choices between3̂and ♭3̂in rock are complex but principled, guided by a small set of interacting preferences, and that blue notes are uncommon but do occasionally occur.

Auditory processing, linguistic prosody awareness, and word reading in Mandarin-speaking children learning English

This study examined language-specific links among auditory processing, linguistic prosody awareness, and Mandarin (L1) and English (L2) word reading in 61 Mandarin-speaking, English-learning children. Three auditory discrimination abilities were measured: pitch contour, pitch interval, and rise time (rate of intensity change at tone onset). Linguistic prosody awareness was measured three ways: Mandarin tone perception, English stress perception, and English stress production. A Chinese character recognition task was the Mandarin L1 reading metric. English L2 word reading was assessed by English real word reading and nonword decoding tasks. The importance of the auditory processing measures to reading was different in the two languages. Pitch contour discrimination predicted Mandarin L1 word reading and rise time discrimination predicted English L2 word reading, after controlling for age and nonverbal IQ. For the prosodic and phonological measures, Mandarin tone perception, but not rhyme awareness, predicted Chinese character recognition after controlling for age and nonverbal IQ. In contrast, English rhyme awareness predicted more unique variance in English real word reading and nonword decoding than did English stress perception and production. Linguistic prosody awareness appears to play a more important role in L1 word reading than phonological awareness; while the reverse seems true for English L2 word reading in Mandarin-speaking children. Taken together, auditory processing, language-specific linguistic prosody awareness, and phonological awareness play different roles in L1/L2 reading, reflecting different prosodic and segmental structures between Mandarin and English.

Robust Harmonic Features for Classification-Based Pitch Estimation.

Pitch estimation in diverse naturalistic audio streams remains a challenge for speech processing and spoken language technology. In this study, we investigate the use of robust harmonic features for classification-based pitch estimation. The proposed pitch estimation algorithm is composed of two stages: pitch candidate generation and target pitch selection. Based on energy intensity and spectral envelope shape, five types of robust harmonic features are proposed to reflect pitch associated harmonic structure. A neural network is adopted for modeling the relationship between input harmonic features and output pitch salience for each specific pitch candidate. In the test stage, each pitch candidate is assessed with an output salience that indicates the potential as a true pitch value, based on its input feature vector processed through the neural network. Finally, according to the temporal continuity of pitch values, pitch contour tracking is performed using a hidden Markov model (HMM), and the Viterbi algorithm is used for HMM decoding. Experimental results show that the proposed algorithm outperforms several state-of-the-art pitch estimation methods in terms of accuracy in both high and low levels of additive noise.

Rhythm in Ethiopian English: Implications for the Teaching of English Prosody

In order to verify that English speeches produced by Ethiopian speakers fall under syllable-timed or stress-timed rhythm, the study tried to examine the nature of stress and rhythm in the pronunciation of Ethiopian speakers of English by focusing on one language group speaking Amharic as a native language. Using acoustic analysis of the speeches recorded from four Amharic speaking learners and two Canadian native speakers of English, comparison was made between pitch contours and length of speeches between speech samples of Amharic speakers with native speakers who are used in this study as a point of reference. The result of acoustic analysis showed that Amharic native samples displayed actual peaks on almost all words, taking longer time of articulation. It can be said that acoustic measures the study used for prosodic assessment of Ethiopian English exemplified the most occurring production tendencies of pronunciation that learners should give attention to. English pronunciation teaching to Ethiopians should involve the practice of stressing, un-stressing and rhythm to help learners improve their pronunciation from the influence of the syllable-timed rhythm of their mother tongue.

Cognitive basis of individual differences in speech perception, production and representations: The role of domain general attentional switching.

This study investigated whether individual differences in cognitive functions, attentional abilities in particular, were associated with individual differences in the quality of phonological representations, resulting in variability in speech perception and production. To do so, we took advantage of a tone merging phenomenon in Cantonese, and identified three groups of typically developed speakers who could differentiate the two rising tones (high and low rising) in both perception and production [+Per+Pro], only in perception [+Per-Pro], or in neither modalities [-Per-Pro]. Perception and production were reflected, respectively, by discrimination sensitivity d' and acoustic measures of pitch offset and rise time differences. Components of event-related potential (ERP)-the mismatch negativity (MMN) and the ERPs to amplitude rise time-were taken to reflect the representations of the acoustic cues of tones. Components of attention and working memory in the auditory and visual modalities were assessed with published test batteries. The results show that individual differences in both perception and production are linked to how listeners encode and represent the acoustic cues (pitch contour and rise time) as reflected by ERPs. The present study has advanced our knowledge from previous work by integrating measures of perception, production, attention, and those reflecting quality of representation, to offer a comprehensive account for the underlying cognitive factors of individual differences in speech processing. Particularly, it is proposed that domain-general attentional switching affects the quality of perceptual representations of the acoustic cues, giving rise to individual differences in perception and production.

Global Music Recordings Support the Motor Constraint Hypothesis for Human and Avian Song Contour

There has recently been renewed interest in using quantitative data to explore questions about musical universals. One explanation for certain musical universals is that they reflect ways of singing that are most energetically efficient, as opposed to biological specializations for human music. Previous research found support for this “motor constraint hypothesis” by comparing pitch contour shapes in samples of human and avian songs, but the sample of human songs was limited to notated scores of European and Chinese folk songs from the Essen database. Here we test this hypothesis using a more diverse global sample of human music recordings from the Garland Encyclopedia of World Music. By directly comparing pitch contour shapes in a diverse sample of human songs and bird songs, we found that both human and bird songs tend to employ similar descending/arched melodic contours despite substantial differences in absolute pitch and duration. This preference was consistent for both Western and non-Western songs. Surprisingly, we also found that the global samples of human and bird song contours were significantly more correlated with one another than either was with the Essen contours. Our findings of broad cross-cultural and cross-species parallels support the motor constraint hypothesis for melodic contour. More generally, our findings demonstrate the importance of greater collaboration between ethnomusicology and music psychology.

F0 thoughs and prosodic phrasing: an investigation into the linguistic information contained in a speaker's baseline when reading

This paper examines some aspects of the prosody of reading aloud. The pitch contour of a read text was examined, and the low troughs, or valleys, in the contour were identified. The pitch of these troughs, and their position in the text, was found to relate systematically to the structure of the text. This suggests that the speaker’s pitch baseline may carry important linguistic information.

Categorical perception of pitch: Influence of language tone, linguistic meaning, and pitch contour

Introduction: Pitch is important for perception of speech. It is an imperative acoustic cue for differentiating gender, age, emotion and culture, etc. In certain languages, pitch also changes the linguistic meaning of the word. Mandarin, Cantonese, Thai, etc. (tonal languages) are few such languages where the pitch contour varies the meaning of the word. Researchers reported that language tone and pitch contour influence the pitch perception, but the results were inconclusive. The role of linguistic meaning was also sparsely investigated in the context of pitch perception. Thus, the present study was designed to assess the influence of language tone, linguistic meaning, and pitch contour on the perception of pitch. Methods: Fifty adult Mandarin and Kannada speaking individuals were selected, and their pitch perception abilities were measured using a 15-step categorical perception paradigm. The stimuli were Mandarin meaningful and nonmeaningful syllables varying in their pitch contour from rising to falling fundamental frequency in one set and falling to rising fundamental frequency in another set of continuum. Results: Univariate ANOVA was used to compare the effect of language background, linguistic meaning, and pitch contour on the perception of pitch. Results indicate no significant effect of linguistic background (P > 0.05) and linguistic meaning (P > 0.05), but the mean values were significantly different across pitch contour (P = 0.001). Conclusion: The language tone and linguistic meaning have no significant influence on the pitch perception, but the categorical boundary was wider for Kannada language participants and for nonmeaningful stimuli. Pitch contour significantly affects the perception of pitch. There are differential perceptual processes which are dependent on the native languages.

Speech Signal Analysis and Pattern Recognition in Diagnosis of Dysarthria.

Background:Dysarthria refers to a group of disorders resulting from disturbances in muscular control over the speech mechanism due to damage of central or peripheral nervous system. There is wide subjective variability in assessment of dysarthria between different clinicians. In our study, we tried to identify a pattern among types of dysarthria by acoustic analysis and to prevent intersubject variability.Objectives:(1) Pattern recognition among types of dysarthria with software tool and to compare with normal subjects. (2) To assess the severity of dysarthria with software tool.Materials and Methods:Speech of seventy subjects were recorded, both normal subjects and the dysarthric patients who attended the outpatient department/admitted in AIMS. Speech waveforms were analyzed using Praat and MATHLAB toolkit. The pitch contour, formant variation, and speech duration of the extracted graphs were analyzed.Results:Study population included 25 normal subjects and 45 dysarthric patients. Dysarthric subjects included 24 patients with extrapyramidal dysarthria, 14 cases of spastic dysarthria, and 7 cases of ataxic dysarthria. Analysis of pitch of the study population showed a specific pattern in each type. F0 jitter was found in spastic dysarthria, pitch break with ataxic dysarthria, and pitch monotonicity with extrapyramidal dysarthria. By pattern recognition, we identified 19 cases in which one or more recognized patterns coexisted. There was a significant correlation between the severity of dysarthria and formant range.Conclusions:Specific patterns were identified for types of dysarthria so that this software tool will help clinicians to identify the types of dysarthria in a better way and could prevent intersubject variability. We also assessed the severity of dysarthria by formant range. Mixed dysarthria can be more common than clinically expected.

“Softened” Voice Quality in Poetry Reading: An Acoustic Study

This study explores the acoustic properties of a certain “softened” voice quality adopted by some professional poetry readers for emotive expression. We show that several acoustic features may serve as cues for softened voice, including: breathy voice, low intensity, and, possibly, reduced tempo and restrained dynamics of intensity and pitch contours. In addition, we show that different speakers may achieve the effect of voice softening in different ways. Our results demonstrate the contribution of the vocal dimension to the experience of poetry. Although this is essentially a case study of the subjective perceptions of one individual, the results are consistent, and we show their potential to be generalized across listeners.

Normalization of lexical tones and nonlinguistic pitch contours: Implications for speech-specific processing mechanism.

Context is indispensable for accurate tone perception, especially when the target tone system is as complex as that of Cantonese. However, not all contexts are equally beneficial. Speech contexts are usually more effective in improving lexical tone identification than nonspeech contexts matched in pitch information. Some potential factors which may contribute to these unequal effects have been proposed but, thus far, their plausibility remains unclear. To shed light on this issue, the present study compares the perception of lexical tones and their nonlinguistic counterparts under specific contextual (speech, nonspeech) and attentional (with/without focal attention) conditions. The results reveal a prominent congruency effect-target sounds tend to be identified more accurately when embedded in contexts of the same nature (speech/nonspeech). This finding suggests that speech and nonspeech sounds are partly processed by domain-specific mechanisms and that information from the same domain can be integrated more effectively than that from different domains. Therefore, domain-specific processing of speech could be the most likely cause of the unequal context effect. Moreover, focal attention is not a prerequisite for extracting contextual cues from speech and nonspeech during perceptual normalization. This finding implies that context encoding is highly automatic for native listeners.

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.

The reconstruction of F. Kuršaitis syllable tones: initiation of new discusion

It is well known, that tones of Lithuanian language for the first time have been described and illustrated using musical notes in the mid of 19th century by Friedrich Kurschat (lt. Frydrichas Kuršaitis). No single attempt was made in order to analyze in-depth what specific prosodic features were covered by this material since the article of prof. A. Girdenis appeared in 2008. He concluded, that tone distribution is generally based on pitch range and contour differences (i.e. rising vs falling tone opposition). An alternative way of reconstruction proposed here reveals additional features which should be taken in to account as well. Measurements of prosodic parameters (i.e. pitch range, shape and vowel length) show that tones differ in terms of rate of pitch change and duration. Rising tone (or to be more precise – sustained tone) can be defined as having longer duration and less intensive rate of pitch change while the falling tone has opposite parameters – shorter duration and abrupt, steep pitch change. The phonetic nature of Lithuanian language tones therefore should be considered as a complex one.

Tone and intonation in discourse management – How do speakers of Standard Vietnamese initiate a repair?

This paper investigates the intonation of other-initiation of repair in Standard Vietnamese and provides an analysis of its interaction with lexical tone at the word level. Results from both single-word and multi-word utterances show that speakers make predominant use of a rising pitch contour to mark other-initiation of repair, a contour that has been found in a large number of languages. This rise occurs consistently at the right edge of utterances and may be analysed as a phonetic reflex of a high boundary tone that can overlap, partially or completely, with the lexical tone of an utterance-final word. Further, the study demonstrates the application of talk-in-interaction to the study of the relation between lexical tone and intonation in tone languages.

Intonation classification for L2 English speech using multi-distribution deep neural networks

This paper investigates the use of multi-distribution deep neural networks (MD-DNNs) for automatic intonation classification in second-language (L2) English speech. If a classified intonation is different from the target one, we consider that mispronunciation is detected and appropriate diagnostic feedback can be provided thereafter. To transcribe speech data for intonation classification, we propose the RULF labels which are used to transcribe an intonation as rising, upper, lower or falling. These four types of labels can be further merged into two groups – rising and falling. Based on the annotated data from 100 Mandarin and 100 Cantonese learners, we develop an intonation classifier, which considers only 8 frames (i.e., 80 ms) of pitch value prior to the end of the pitch contour over an intonational phrase (IP). This classifier determines the intonation of L2 English speech as either rising or falling with an accuracy of 93.0%.