Phoneme Boundary Research Articles

Temporal feature-based approaches for enhancing phoneme boundary detection and masking in speech

Temporal feature-based approaches for enhancing phoneme boundary detection and masking in speech

MORPHOLOGY AND MORPHEMOLOGY: WORD STRUCTURE AND MORPHOLOGICAL ASPECTS OF LANGUAGE

The article focuses on analyzing the foundational theoretical tenets of morphemology and morphology within contemporary Ukrainian linguistics, emphasizing their intrinsic interrelation. A comprehensive examination of the morpheme as the fundamental linguistic entity for morphemological studies is undertaken. The primary attributes of a morpheme as a linguistic unit are elucidated, facilitating a more proficient comprehension of the principles underlying the morphemic analysis of words. Furthermore, the research delves into the grammatical meanings embodied by morphemes within specific parts of speech, drawing on Ukrainian language lexemes for illustration. The discourse provides a rationale for considering morphemology as an autonomous branch of linguistics, intricately linked with morphology and derivatology. The article delineates distinctions in the application of terms such as "morphemics" versus "morphemology" and "morpheme" versus "morph." A crucial assertion is advanced, substantiating that a morpheme, functioning as the smallest semantically significant constituent of a word, can simultaneously convey lexical, grammatical, and word-formational meanings. The correlation between morphemology and morphology is substantiated by the integral semantics inherent in words, a phenomenon derived from the amalgamation of lexical and grammatical meanings. The confluence of these meanings establishes a word's classification within a specific grammatical category (part of speech) and its affiliation with a particular word-formational type. Similar to a word form, a morpheme exhibits reproducibility in language, possesses a semiological function, and serves to convey both subject (via the root) and non-subject (via affixes) meanings. As with other linguistic entities, morphemes and word forms can be regarded as historical categories, prompting the differentiation of word formation into historical and synchronic aspects. Throughout the historical evolution of a language, alterations in word structure manifest through phonetic changes, the loss of productive affixes, and modifications in the phonemic boundaries of morphemes. Consequently, the framework for synchronic morphemic analysis must not be indiscriminately applied to other synchronic facets of the language.

Improving Text-Independent Forced Alignment to Support Speech-Language Pathologists with Phonetic Transcription.

Problem: Phonetic transcription is crucial in diagnosing speech sound disorders (SSDs) but is susceptible to transcriber experience and perceptual bias. Current forced alignment (FA) tools, which annotate audio files to determine spoken content and its placement, often require manual transcription, limiting their effectiveness. Method: We introduce a novel, text-independent forced alignment model that autonomously recognises individual phonemes and their boundaries, addressing these limitations. Our approach leverages an advanced, pre-trained wav2vec 2.0 model to segment speech into tokens and recognise them automatically. To accurately identify phoneme boundaries, we utilise an unsupervised segmentation tool, UnsupSeg. Labelling of segments employs nearest-neighbour classification with wav2vec 2.0 labels, before connectionist temporal classification (CTC) collapse, determining class labels based on maximum overlap. Additional post-processing, including overfitting cleaning and voice activity detection, is implemented to enhance segmentation. Results: We benchmarked our model against existing methods using the TIMIT dataset for normal speakers and, for the first time, evaluated its performance on the TORGO dataset containing SSD speakers. Our model demonstrated competitive performance, achieving a harmonic mean score of 76.88% on TIMIT and 70.31% on TORGO. Implications: This research presents a significant advancement in the assessment and diagnosis of SSDs, offering a more objective and less biased approach than traditional methods. Our model's effectiveness, particularly with SSD speakers, opens new avenues for research and clinical application in speech pathology.

Using Phoneme Discrimination to Help Emergent Bilinguals With Reading Disabilities Acquire New Sounds

Phoneme discrimination is the ability to detect subtle similarities and differences between phonemes. Phoneme discrimination is a strong predictor of reading development and poor phoneme discrimination may predict reading disabilities (Lyytinen et al., 2004). The ability to discriminate phonemes may be an even more critical skill for Emergent Bilinguals (EBs, also known as English Learners) and EBs with reading disabilities because they need to enhance their perception of phoneme boundaries to enhance their word reading ability. As EB populations in schools increase, addressing phoneme discrimination gaps becomes increasingly important. Classroom instruction should include repeated exposure to differentiating phonemes with known high frequency words and minimal pairs to develop a strong foundation for discerning phonetic features.

Perceptual effects of interpolated Austrian and German standard varieties

This article focuses on the perception of standard varieties produced by Austrian and German TV newscasters from the perspective of listeners from both countries, Germany and Austria. Thus, the paper's sociolinguistic scope is located in the pluricentric realm. It assesses (the perception of) standard language variation on fine phonetic levels. In addition to naturally produced stimuli (read sentences), “intermediate” samples were generated by means of a two-step interpolation procedure: First, the symbolic phone sequences were aligned with a Levenshtein-distance algorithm. Second, a phone-level Dynamic-Time-Warping (DTW) algorithm was applied to align the two utterances on a frame level, taking phoneme boundaries into account. Additionally, the spectrum and the fundamental frequency (F0) contour of the utterances was manipulated to be either interpolated or fixed to a given speaker. This procedure allowed for assessing these features’ contribution to listeners’ judgments of whether a given utterance sounds as if spoken by a speaker from (rather) Germany or (rather) Austria. Results of the judgment task showed that the interpolated samples were perceived in a continuous fashion, similarly by both groups, and with overall greater reliance on spectral than F0 information. These findings suggest that even fine phonetic differences between Standard German from Germany and Austria are recognized and evaluated by listeners from both countries. An overall bias towards perceiving all speech samples as closer to the listeners’ own national standard points to a factor of familiarity with one's own and uncertainty towards the ‘foreign’ standard. The similar degree of this bias indicates that both groups have similar levels of familiarity with their own and uncertainty about the other standard variety.

Unattended distributional training can shift phoneme boundaries

AbstractListeners are sensitive to speech sounds’ probability distributions. Distributional training (DT) studies with adults typically involve conscious activation of phoneme labels. We show that distributional exposure can shift existing phoneme boundaries (Spanish /e/–/i/) pre-attentively. Using a DT paradigm involving two bimodal distributions we assessed listener's neural discrimination across three sounds, showing pre-to-post-test improvement for the two adjacent sounds that fell into different clusters of the trained distribution than for those that fell into one cluster. Upon unattended exposure to an intricate stimulus set, listeners thus relocate native phoneme boundaries. We assessed whether the paradigm also works for category creation (Spanish establishing a duration contrast), where it has methodological advantages over the usual unimodal-versus-bimodal paradigm. DT yielded a greater effect for the /e/–/i/ boundary shift than for duration contrast creation. It seems that second-language phoneme contrasts similar to native ones might be easier to acquire than new contrasts.

Early linguistic experience shapes bilingual adults\u2019 hearing for phonemes in both languages

English and Mandarin Chinese differ in the voice onset times (VOTs) of /b/ and /p/. Hence the way bilinguals perceive these sounds may show ‘tuning’ to the language-specific acoustic structure of a bilingual’s languages (a discrete model), or a shared representation across languages (a unitary model). We investigated whether an individual’s early childhood exposure influences their model of phoneme perception across languages, in a large sample of early English-Mandarin bilingual adults in Singapore (N = 66). As preregistered, we mapped identification functions on a /b/-/p/ VOT continuum in each language. Bilingual balance was estimated using principal components analysis and entered into GLMMs of phoneme boundary and slope. VOT boundaries were earlier for English than Mandarin, and bilingual balance predicted the slope of the transition between categories across both languages: Those who heard more English from an earlier age showed steeper category boundaries than those who heard more Mandarin, suggesting early bilinguals may transfer their model for how phonemes differ from their earlier/stronger languages to later/weaker languages. We describe the transfer model of discrete phoneme representations and its implications for use of the phoneme identification task in diverse populations.

Adult perception of stop consonant voicing in American-English-learning toddlers: Voice onset time and secondary cues.

Most studies of speech perception employ highly controlled stimuli. It is not always clear how such results extend to the processing of natural speech. In a series of experiments, we progressively explored the role of voice onset time (VOT) and potential secondary cues in adult labeling of stressed syllable-initial /b d p t/ produced by typically developing two-year-old learners of American English. Taken together, the results show the following: (a) Adult listeners show phoneme boundaries in labeling functions comparable to what have been established for adult speech. (b) Adult listeners can be sensitive to distributional properties of the stimulus set, even in a study that employs highly varied naturalistic productions from multiple speakers. (c) Secondary cues are available in the speech of two-year-olds, and these may influence listener judgments. Cues may differ across places of articulation and the VOT continuum. These results can lend insight into how clinicians judge child speech during assessment and also have implications for our understanding of the role of primary and secondary acoustic cues in adult perception of child speech.

An analysis of the perception of stop consonants in bilinguals and monolinguals in different phonetic contexts: A range-based language cueing approach.

Bilinguals' observed perceptual shift across language contexts for shared acoustic properties between their languages supports the idea that bilinguals, but not monolinguals, develop two phonemic representations for the same acoustic property. This phenomenon is known as the double phonemic boundary. This investigation replicated previous findings of bilinguals' double phonemic boundary across a series of go/no-go tasks while controlling for known confounding effects in speech perception (i.e., contrast effects) and differences in resource allocation between bilinguals and monolinguals (i.e., left-hand or right-hand response). Using a range-base language cueing approach, we designed 2 experiments. The first experiment tested whether a voice onset time (VOT) range representative of either Spanish or English phonetic categories can cue bilinguals, but not monolinguals, to use language-specific perceptual routines. The second experiment tested a VOT range with a mixture of Spanish and English phonetic categories to determine whether directing attention to a specific phonetic category can disambiguate the competition of the nonattended category. The results for Experiment 1 showed that bilinguals can rely on the distributional patterns of their native phonetic categories to activate specific language modes. Experiment 2 showed that attention can change the weight given to a native phonetic distinction. However, this process is restricted by the internal phonetic composition of the native language(s).

Neural Correlates of Phonetic Adaptation as Induced by Lexical and Audiovisual Context.

When speech perception is difficult, one way listeners adjust is by reconfiguring phoneme category boundaries, drawing on contextual information. Both lexical knowledge and lipreading cues are used in this way, but it remains unknown whether these two differing forms of perceptual learning are similar at a neural level. This study compared phoneme boundary adjustments driven by lexical or audiovisual cues, using ultra-high-field 7-T fMRI. During imaging, participants heard exposure stimuli and test stimuli. Exposure stimuli for lexical retuning were audio recordings of words, and those for audiovisual recalibration were audio-video recordings of lip movements during utterances of pseudowords. Test stimuli were ambiguous phonetic strings presented without context, and listeners reported what phoneme they heard. Reports reflected phoneme biases in preceding exposure blocks (e.g., more reported /p/ after /p/-biased exposure). Analysis of corresponding brain responses indicated that both forms of cue use were associated with a network of activity across the temporal cortex, plus parietal, insula, and motor areas. Audiovisual recalibration also elicited significant occipital cortex activity despite the lack of visual stimuli. Activity levels in several ROIs also covaried with strength of audiovisual recalibration, with greater activity accompanying larger recalibration shifts. Similar activation patterns appeared for lexical retuning, but here, no significant ROIs were identified. Audiovisual and lexical forms of perceptual learning thus induce largely similar brain response patterns. However, audiovisual recalibration involves additional visual cortex contributions, suggesting that previously acquired visual information (on lip movements) is retrieved and deployed to disambiguate auditory perception.

Categorical Auditory Working Memory in Crows.

SummaryThe ability to group sensory data into behaviorally meaningful classes and to maintain these perceptual categories active in working memory is key to intelligent behavior. Here, we show that carrion crows, highly vocal and cognitively advanced corvid songbirds, possess categorical auditory working memory. The crows were trained in a delayed match-to-category task that required them to flexibly match remembered sounds based on the upward or downward shift of the sounds' frequency modulation. After training, the crows instantaneously classified novel sounds into the correct auditory categories. The crows showed sharp category boundaries as a function of the relative frequency interval of the modulation. In addition, the crows generalized frequency-modulated sounds within a category and correctly classified novel sounds kept in working memory irrespective of other acoustic features of the sound. This suggests that crows can form and actively memorize auditory perceptual categories in the service of cognitive control of their goal-directed behaviors.

CONCEPTUALLY CUED PERCEPTUAL CATEGORIZATION IN ADULT L2 LEARNERS

AbstractPrevious studies attest that early bilinguals can modify their perceptual identification according to the fine-grained phonetic detail of the language they believe they are hearing. Following Gonzales et al. (2019), we replicate the double phonemic boundary effect in late learners (LBs) using conceptual-based cueing. We administered a forced choice identification task to 169 native English adult learners of Spanish in two sessions. In both sessions, participants identified the same /b/-/p/ voicing continuum, but language context was cued conceptually using the instructions. The data were analyzed using Bayesian multilevel regression. Learners categorized the continuum in a similar manner when they believed they were hearing English. However, when they believed they were hearing Spanish, “voiceless” responses increased as a function of L2 proficiency. This research demonstrates the double phonemic boundary effect can be conceptually cued in LBs and supports accounts positing selective activation of independent perception grammars in L2 learning.

The relationship between phonemic category boundary changes and perceptual adjustments to natural accents.

People often experience difficulties when they first hear a novel accent. Prior research has shown that relatively fast natural accent accommodation can occur. However, there has been little investigation of the underlying perceptual mechanism that drives the learning. The current study examines whether phonemic boundary changes play a central role in natural accent accommodation. Two well-established boundary shifting phenomena were used here-recalibration and selective adaptation-to index the flexibility of phonemic category boundaries. Natural accent accommodation was measured with a task in which listeners heard accented words and nonwords before and after listening to English sentences produced by one of two native Mandarin Chinese speakers with moderate accents. In two experiments, participants completed recalibration, selective adaptation, and natural accent accommodation tasks focusing on a consonant contrast that is difficult for native Chinese speakers to produce. We found that: (a) On the accent accommodation task, participants showed an increased endorsement of accented/mispronounced words after exposure to a speaker's accented speech, indicating a potential relaxation of criteria in the word recognition process; (b) There was no strong link between recalibrating phonemic boundaries and natural accent accommodation; (c) There was no significant correlation between recalibration and selective adaptation. These results suggest that recalibration of phonemic boundaries does not play a central role in natural accent accommodation. Instead, there is some evidence suggesting that natural accent accommodation involves a relaxation of phonemic categorization criteria. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Effect of Music Training on Categorical Perception of Speech and Music.

Background and ObjectivesThe aim of this study is to evaluate the effect of music training on the characteristics of auditory perception of speech and music. The perception of speech and music stimuli was assessed across their respective stimulus continuum and the resultant plots were compared between musicians and non-musicians.Subjects and MethodsThirty musicians with formal music training and twenty-seven non-musicians participated in the study (age: 20 to 30 years). They were assessed for identification of consonant-vowel syllables (/da/ to /ga/), vowels (/u/ to /a/), vocal music note (/ri/ to /ga/), and instrumental music note (/ri/ to /ga/) across their respective stimulus continuum. The continua contained 15 tokens with equal step size between any adjacent tokens. The resultant identification scores were plotted against each token and were analyzed for presence of categorical boundary. If the categorical boundary was found, the plots were analyzed by six parameters of categorical perception; for the point of 50% crossover, lower edge of categorical boundary, upper edge of categorical boundary, phoneme boundary width, slope, and intercepts.ResultsOverall, the results showed that both speech and music are perceived differently in musicians and non-musicians. In musicians, both speech and music are categorically perceived, while in non-musicians, only speech is perceived categorically.ConclusionsThe findings of the present study indicate that music is perceived categorically by musicians, even if the stimulus is devoid of vocal tract features. The findings support that the categorical perception is strongly influenced by training and results are discussed in light of notions of motor theory of speech perception.

Audiovisual and lexical cues do not additively enhance perceptual adaptation

When listeners experience difficulty in understanding a speaker, lexical and audiovisual (or lipreading) information can be a helpful source of guidance. These two types of information embedded in speech can also guide perceptual adjustment, also known as recalibration or perceptual retuning. With retuning or recalibration, listeners can use these contextual cues to temporarily or permanently reconfigure internal representations of phoneme categories to adjust to and understand novel interlocutors more easily. These two types of perceptual learning, previously investigated in large part separately, are highly similar in allowing listeners to use speech-external information to make phoneme boundary adjustments. This study explored whether the two sources may work in conjunction to induce adaptation, thus emulating real life, in which listeners are indeed likely to encounter both types of cue together. Listeners who received combined audiovisual and lexical cues showed perceptual learning effects similar to listeners who only received audiovisual cues, while listeners who received only lexical cues showed weaker effects compared with the two other groups. The combination of cues did not lead to additive retuning or recalibration effects, suggesting that lexical and audiovisual cues operate differently with regard to how listeners use them for reshaping perceptual categories. Reaction times did not significantly differ across the three conditions, so none of the forms of adjustment were either aided or hindered by processing time differences. Mechanisms underlying these forms of perceptual learning may diverge in numerous ways despite similarities in experimental applications.

An Optimal Feature Parameter Set Based on Gated Recurrent Unit Recurrent Neural Networks for Speech Segment Detection

Speech segment detection based on gated recurrent unit (GRU) recurrent neural networks for the Kurdish language was investigated in the present study. The novelties of the current research are the utilization of a GRU in Kurdish speech segment detection, creation of a unique database from the Kurdish language, and optimization of processing parameters for Kurdish speech segmentation. This study is the first attempt to find the optimal feature parameters of the model and to form a large Kurdish vocabulary dataset for a speech segment detection based on consonant, vowel, and silence (C/V/S) discrimination. For this purpose, four window sizes and three window types with three hybrid feature vector techniques were used to describe the phoneme boundaries. Identification of the phoneme boundaries using a GRU recurrent neural network was performed with six different classification algorithms for the C/V/S discrimination. We have demonstrated that the GRU model has achieved outstanding speech segmentation performance for characterizing Kurdish acoustic signals. The experimental findings of the present study show the significance of the segment detection of speech signals by effectively utilizing hybrid features, window sizes, window types, and classification models for Kurdish speech.

Interleaved lexical and audiovisual information can retune phoneme boundaries.

To adapt to situations in which speech perception is difficult, listeners can adjust boundaries between phoneme categories using perceptual learning. Such adjustments can draw on lexical information in surrounding speech, or on visual cues via speech-reading. In the present study, listeners proved they were able to flexibly adjust the boundary between two plosive/stop consonants, /p/-/t/, using both lexical and speech-reading information and given the same experimental design for both cue types. Videos of a speaker pronouncing pseudo-words and audio recordings of Dutch words were presented in alternating blocks of either stimulus type. Listeners were able to switch between cues to adjust phoneme boundaries, and resulting effects were comparable to results from listeners receiving only a single source of information. Overall, audiovisual cues (i.e., the videos) produced the stronger effects, commensurate with their applicability for adapting to noisy environments. Lexical cues were able to induce effects with fewer exposure stimuli and a changing phoneme bias, in a design unlike most prior studies of lexical retuning. While lexical retuning effects were relatively weaker compared to audiovisual recalibration, this discrepancy could reflect how lexical retuning may be more suitable for adapting to speakers than to environments. Nonetheless, the presence of the lexical retuning effects suggests that it may be invoked at a faster rate than previously seen. In general, this technique has further illuminated the robustness of adaptability in speech perception, and offers the potential to enable further comparisons across differing forms of perceptual learning.

HMM-based Bahasa Indonesia speech synthesis system with hand-segmentation and labeling

In this paper, we compare the naturalness quality of Bahasa Indonesia speech synthesis using festvox automatic- and hand-segmentation and labeling technique to create a speech transcription. First, we developed a 1549 declarative and question sentence phonetically balanced speech corpus uttered by six male and female speakers. We selected 47, 72, 119, 450, 929, and 1379 sentences, respectively for training whilst maintaining the phonetical balance. The objective is to find the least data training for synthesized naturalness evaluation on both automatic- and hand-segmentation and labeling. The evaluation result using the Mel-cepstrum distortion method was 2.9 for hand-segmentation and labeling, 5.36 for automatic with 47 training sentences, respectively which took about 45 minutes to complete. The performance was increased by 2.46 with hand-segmentation and labeling, 4.78 for automatic, with 1379 sentences and about 9 hours of training time. The Mean Opinion Score was 3.98 (hand) and 3.04 for automatic, respectively which is about 18% performance improvement. The automatic segmentation and labeling introduced phoneme boundary errors which may suggest that the necessity to take careful consideration in segmentation and labeling.

Unsupervised Phonetic Segmentation of Classical Arabic Speech Using Forward and Inverse Characteristics of the Vocal Tract

Automatic segmentation of speech is about identifying boundaries of phonemes in a given utterance. This paper presents a strategy driven by cosine distance similarity scores for identifying phoneme boundaries. The proposed strategy helps in the selection of appropriate feature extraction technique for speech segmentation applications. After assessing various state-of-the-art speech processing techniques, a novel combination of forward and inverse characteristics of vocal tract (FICV) is developed. The proposed technique is evaluated on Classical Arabic dataset. Extensive experiments are made to compare the proposed technique with state-of-the-art techniques, including the hidden Markov model-based forced alignment procedures. The results show that proposed technique has total error rate of 14.48%, while the accuracy is 85.2% within 10 ms alignment error. When compared with the existing state-of-the-art technique, the proposed technique outperforms by 12.29% and 22.73% in terms of error rates and alignment accuracies, respectively, which signifies the potential of using FICV in speech segmentation.

Effect of Clear Speech on the Duration of Silent Intervals at Syntactic and Phonemic Boundaries in the Speech of Individuals With Parkinson Disease.

Purpose The purpose of the current investigation was to determine the extent to which individuals with and without Parkinson disease (PD) modified silent interval durations when using a clear speaking style. Method Ten individuals with idiopathic PD and 10 older adult control speakers produced a reading passage using both habitual and clear speaking styles. Silent intervals lasting 15 ms and longer were identified and extracted. Each silent interval was categorized according to the surrounding syntactic context of the reading passage. In addition, voiceless stop gaps that occurred within words, phrases, or clauses were categorized by the preceding phonemic context. Results Statistical analyses revealed that all participants increased silent interval duration with a clear speaking style at inter-sentence and intra-sentence syntactic boundaries. Compared to controls, individuals with PD exhibited significantly less increase in silent interval durations at these syntactic boundaries. Control speakers also increased silent stop gap durations in the clear speaking style regardless of preceding phonemic context. Individuals with PD, however, only increased stop gap duration when the silent interval was preceded by a sonorant. Conclusion These findings suggest that speakers with PD exhibit less clarity-related increase in silent interval duration than control speakers. In addition, speakers with PD exhibited significant increases in silent interval duration that coincided with syntactic boundaries of the reading passage but little to no clarity-related modulation of stop gap intervals. Therefore, these data suggest that speakers with PD exhibited changes in silent interval durations that were more so associated with modulation of speech prosody than articulation when using a clearer speaking style.