Phonetic Cues Research Articles

Infant preference for specific phonetic cue relations in the contrast between voiced and voiceless stops.

Acoustic variability in the speech input has been shown, in certain contexts, to be beneficial during infants' acquisition of sound contrasts. One approach attributes this result to the potential of variability to make the stability of individual cues visible. Another approach suggests that, instead of highlighting individual cues, variability uncovers stable relations between cues that signal a sound contrast. Here, we investigate the relation between Voice Onset Time and the onset of F1 formant frequency, two cues that subserve the voicing contrast in German. First, we verified that German-speaking adults' use of VOT to categorize voiced and voiceless stops is dependent on the value of the F1 onset frequency, in the specific form of a so-called trading relation. Next, we tested whether 6-month-old German learning infants exhibit differential sensitivity to stimulus continua in which the cues varied to an equal extent, but either adhered to the trading relation established in the adult experiment or adhered to a reversed relation. Our results present evidence that infants prefer listening to speech in which phonetic cues conform to certain cue trading relations over cue relations that are reversed.

Machine-Based and Auditory Identification of Slavic Languages

This paper presents a comparison of auditory and machine-based identification of linguistic origins. Two studies were conducted to assess the ability of lay listeners and a stateof-the-art machine approach to identify Slavic L1 from delexicalized speech samples. The first study involved 228 native speakers of the four Slavic languages (Bulgarian, Czech, Polish and Russian) who had not received any prior training in Slavic philology, phonetics, linguistics, or forensic science. Their task was to identify the linguistic origins of speakers when exposed to limited phonetic cues. The stimuli consisted of meaningless logatomes to control for the lexical information. The second study employed machine-based identification of a spoken language, based on two distinct approaches: (1) formant structure of phonetic signal and (2) a neural network and vector representation of speech samples. The data showed that Slavic native speakers, even when exposed to limited auditory cues, are able to identify speakers’ L1s. Interestingly, in the context of the Bulgarian language, the machine-based identification method performed better than the lay listeners. The results of the experiments provide insight into the advantages of hybrid approaches in investigations related to LADO (Language Analyses for the Determination of Origin). Furthermore, the outcomes of this comparison may contribute to the debate on the involvement of native speakers in L1 identification procedures for closely related languages.

Generational differences in sensitivity to phonetic cues: Accentuation patterns of novel words

Generational differences in sensitivity to phonetic cues: Accentuation patterns of novel words

Prosody matters: Preserved prominence marking strategies in people with Parkinson's disease independent of motor status.

While many studies focus on segmental variation in Parkinsonian speech, little is known about prosodic modulations reflecting the ability to adapt to communicative demands in people with Parkinson's disease (PwPD). This type of prosodic modulation is important for social interaction, and it involves modifications in speech melody (intonational level) and articulation of consonants and vowels (segmental level). The present study investigates phonetic cues of prosodic modulations with respect to different focus structures in mild dysarthric PwPD as a function of levodopa. Acoustic and kinematic speech parameters of 25 PwPD were assessed in two motor conditions. Speech production data from PwPD were collected before (medication-OFF) and after levodopa intake (medication-ON) by means of 3-D electromagnetic articulography. On the acoustic level, intensity, pitch, and syllable durations were analyzed. On the kinematic level, movement duration and amplitude were investigated. Spatio-temporal modulations of speech parameters were examined and compared across three different prosodic focus structures (out-of-focus, broad focus, contrastive focus) to display varying speech demands. Overall, levodopa had beneficial effects on motor performance, speech loudness, and pitch modulation. Acoustic syllable durations and kinematic movement durations did not change, revealing no systematic effects of motor status on the temporal domain. In contrast, there were spatial modulations of the oral articulators: tongue tip movements were smaller and lower lip movements were larger in amplitude under levodopa, reflecting a more agile and efficient articulatory movement under levodopa. Thus, respiratory-phonatory functions and consonant production improved, while syllable duration and tongue body kinematics did not change. Interestingly, prominence marking strategies were comparable between the medication conditions under investigation, and in fact, appear to be preserved in mild dysarthric PwPD.

Phonetic cues to depression: A sociolinguistic perspective

AbstractPhonetic data are used in several ways outside of the core field of phonetics. This paper offers the perspective of one such field, sociophonetics, towards another, the study of acoustic cues to clinical depression. While sociophonetics is interested in how, when, and why phonetic variables cue information about the world, the study of acoustic cues to depression is focused on how phonetic variables can be used by medical professionals as tools to diagnosis. The latter is only interested in identifying phonetic cues to depression, while the former is interested in how phonetic variation cues anything at all. While the two fields fundamentally differ with respect to ontology, epistemology, and methodology, I argue that there are, nonetheless, possible avenues for future engagement, collaboration, and investigation. Ultimately, both fields need to engage with Crip Linguistics for any successful intervention on the relationship between speech and depression.

What do you learn from a single cue? Dimensional reweighting and cue reassociation from experience with a newly unreliable phonetic cue

In language comprehension, we use perceptual cues to infer meanings. Some of these cues reside on perceptual dimensions. For example, the difference between bear and pear is cued by a difference in voice onset time (VOT), which is a continuous perceptual dimension. The present paper asks whether, and when, experience with a single value on a dimension behaving unexpectedly is used by the learner to reweight the whole dimension. We show that learners reweight the whole VOT dimension when exposed to a single VOT value (e.g., 45 ms) and provided with feedback indicating that the speaker intended to produce a /b/ 50% of the time and a /p/ the other 50% of the time. Importantly, dimensional reweighting occurs only if 1) the 50/50 feedback is unexpected for the VOT value, and 2) there is another dimension that is predictive of feedback. When no predictive dimension is available, listeners reassociate the experienced VOT value with the more surprising outcome but do not downweight the entire VOT dimension. These results provide support for perceptual representations of speech sounds that combine cues and dimensions, for viewing perceptual learning in speech as a combination of error-driven cue reassociation and dimensional reweighting, and for considering dimensional reweighting to be reallocation of attention that occurs only when there is evidence that reallocating attention would improve prediction accuracy (Harmon, Z., Idemaru, K., & Kapatsinski, V. 2019. Learning mechanisms in cue reweighting. Cognition, 189, 76–88.).

Secondary predication in Irish and the syntax-prosody interface

Cross-linguistically, secondary predicates may be distinguished from event-modifiers (e.g. adverbs or converbs) and individual-modifiers (e.g. attributive adjectives, participles, or prepositional phrases) via the presence or absence of prosodic processes and phonetic cues. This paper examines the prosodic behavior of secondary predicates in Modern Irish, which can form bare adjectival depictive and resultative secondary predicates. We show that Mod. Irish bare AP secondary predicates are distinguished from surface distributionally equivalent attributive modifiers through the morphophonological system of initial mutation and cues such as phrase-final lengthening and pauses. These facts support an analysis of secondary predicates as extraposition structures that project to a φ-max/ι-boundary, mapping to complex syntactico-semantic representations. Evidence from Italian consonant gemination (raddoppiamento sintattico) and Georgian boundary tones are likewise discussed under the proposed analysis.

How word stress is realized in Thai: evidence from the ordering of coordinate compounds

Abstract This study challenges the widespread belief that Thai lacks word stress, demonstrating its pivotal role in morphophonology. Through a Maximum Entropy analysis, we investigated how specific segmental properties statistically influence speakers’ choices of word order in coordinate compounds. Results indicate a significant effect of phonological weight on the ordering patterns. Specifically, the dispreference for stop codas in final positions and the preference for long or low vowels word-finally converge to differentially distribute phonological weight, ensuring that final syllables are heavier in accordance with the Stress-to-Weight Principle. Additionally, a marginal affinity is observed between the final syllable and the (historical) high-register tone, aligning with the well-documented tone-stress interaction where high tones gravitate towards stressed syllables. These findings provide compelling evidence for the existence of word stress in Thai: compound stress necessarily coincides with word stress, as dictated by the Continuous Column Constraint. Thus, this work suggests that relying solely on phonetic cues is insufficient for identifying stress; instead, a comprehensive analysis incorporating “phonological exponents” is essential to capture the greater phonological contrasts licensed in stressed syllables. This study also contributes to a deeper understanding of metrical and prosodic prominence, revealing that word stress can sometimes be masked by higher-level prominence.

Audiovisual speech asynchrony asymmetrically modulates neural binding

Previous psychophysical and neurophysiological studies in young healthy adults have provided evidence that audiovisual speech integration occurs with a large degree of temporal tolerance around true simultaneity. To further determine whether audiovisual speech asynchrony modulates auditory cortical processing and neural binding in young healthy adults, N1/P2 auditory evoked responses were compared using an additive model during a syllable categorization task, without or with an audiovisual asynchrony ranging from 240 ms visual lead to 240 ms auditory lead. Consistent with previous psychophysical findings, the observed results converge in favor of an asymmetric temporal integration window. Three main findings were observed: 1) predictive temporal and phonetic cues from pre-phonatory visual movements before the acoustic onset appeared essential for neural binding to occur, 2) audiovisual synchrony, with visual pre-phonatory movements predictive of the onset of the acoustic signal, was a prerequisite for N1 latency facilitation, and 3) P2 amplitude suppression and latency facilitation occurred even when visual pre-phonatory movements were not predictive of the acoustic onset but the syllable to come. Taken together, these findings help further clarify how audiovisual speech integration partly operates through two stages of visually-based temporal and phonetic predictions.

Persistent post-concussion symptoms include neural auditory processing in young children.

Difficulty understanding speech following concussion is likely caused by auditory processing impairments. We hypothesized that concussion disrupts pitch and phonetic processing of a sound, cues in understanding a talker. We obtained frequency following responses to a syllable from 120 concussed and 120 control. Encoding of the fundamental frequency (F0), a pitch cue and the first formant (F1), a phonetic cue, was poorer in concussed children. The F0 reduction was greater in the children assessed within 2 weeks of their injuries. Concussions affect auditory processing. Results strengthen evidence of reduced F0 encoding in children with concussion and call for longitudinal study aimed at monitoring the recovery course with respect to the auditory system.

Patterns of phonetic cue switching in older adults

Primary phonetic cues for identifying speech in quiet may be unreliable in background noise, requiring listeners to utilize cues more resistant to masking to accurately recognize speech. Previous experiments demonstrated that individuals rely mainly on voice onset time (VOT) to categorize /bir/-/pir/ sounds in quiet but rely on fundamental frequency (F0) when VOT is masked by noise. As older adults report challenges perceiving speech in noise, the current study investigated whether older adults exhibited poor ability to switch reliance from VOT to F0 in broadband noise. Young (aged 18–30) and older (aged 55+) adults with normal or near-normal hearing categorized /bir/ and /pir/ sounds that were manipulated on a continuum of VOT and F0. No group differences were found in cue weights in quiet or when noise was presented at a signal-to-noise ratio (SNR) of 0 dB. However, when SNR ranged from + 6 to -4 dB, young adults relied on F0 even at the best SNR, whereas older adults continued relying on VOT until significantly poorer SNRs, suggesting that older adults may exhibit maladaptive strategies for phonetic cue switching. Continued use of cues even as they become less reliable may help explain why older adults experience difficulty identifying speech in noise.

The effects of temporal cues, point-light displays, and faces on speech identification and listening effort.

Among the most robust findings in speech research is that the presence of a talking face improves the intelligibility of spoken language. Talking faces supplement the auditory signal by providing fine phonetic cues based on the placement of the articulators, as well as temporal cues to when speech is occurring. In this study, we varied the amount of information contained in the visual signal, ranging from temporal information alone to a natural talking face. Participants were presented with spoken sentences in energetic or informational masking in four different visual conditions: audio-only, a modulating circle providing temporal cues to salient features of the speech, a digitally rendered point-light display showing lip movement, and a natural talking face. We assessed both sentence identification accuracy and self-reported listening effort. Audiovisual benefit for intelligibility was observed for the natural face in both informational and energetic masking, but the digitally rendered point-light display only provided benefit in energetic masking. Intelligibility for speech accompanied by the modulating circle did not differ from the audio-only conditions in either masker type. Thus, the temporal cues used here were insufficient to improve speech intelligibility in noise, but some types of digital point-light displays may contain enough phonetic detail to produce modest improvements in speech identification in noise.

Language-dependent cue weighting in distinctive feature: evidence from the perception of Mandarin high vowels by native English speakers

This study investigates the perception of the three Mandarin high vowels /i, u, y/ after dental, retroflex, and palatal fricatives and affricates (/s/-/ʦ/-/ʦʰ/; /ʂ/-/tʂ/-/tʂʰ/, and /ʨ/, /ʨʰ/, /ɕ/) by native English speakers. The results of the perceptual identification and categorization experiments show that among the three target vowels, the high front rounded vowel /y/ presents the greatest challenge for native English speakers. They have a significantly higher tendency to confuse /y/ with the Mandarin high-back rounded vowel /u/ compared to the Mandarin high-front unrounded vowel /i/, as they perceptually classified /y/ and /u/ into the same English vowel category /u/. The findings of the study suggest that native English speakers adopt a perceptual strategy that differs from that of native Japanese and Korean speakers, relying heavier on the feature of roundness as opposed to backness in perceiving the Mandarin /y/. This study contributes to the perceptual cue weighting field by examining the weighting of phonetic cues (i.e., distinctive features) in Mandarin high vowels by native English speakers. These results hold pedagogical significance as they highlight the importance of targeted perception training for learners of different language backgrounds to enhance both their recognition and reproduction of second language sounds.

Questioning questions - the perception of f0 scaling in German questions between categorical function and continuous attitude.

In previous studies comparing the intonation of questions and statements in German, greater f0 excursions of phrase-final rises have been associated with questions in both read speech and spontaneous speech. This holds for production studies as well as perception studies. However, a major question remains whether these differences are perceived categorically or continuously. Furthermore, we ask whether the differences in f0 scaling correspond to categorical linguistic functions or rather an attitudinal continuum. We conducted three different perception experiments: a classical categorical perception task, an imitation task, and a semantic evaluation task. The results suggest that f0 scaling in phrase-final rises is perceived as a phonetic continuum rather than in phonological categories. Furthermore, the gradual increase of the final rise is associated with a gradual increase in perceived questioning. Lastly, the phonetic cues to this degree of questioning are distinct from those to the other investigated meanings surprise and uncertainty. Accordingly, this study supports the assumption that questioning constitutes an attitudinal meaning in its own right.

Evaluating normalization accounts against the dense vowel space of Central Swedish.

Talkers vary in the phonetic realization of their vowels. One influential hypothesis holds that listeners overcome this inter-talker variability through pre-linguistic auditory mechanisms that normalize the acoustic or phonetic cues that form the input to speech recognition. Dozens of competing normalization accounts exist-including both accounts specific to vowel perception and general purpose accounts that can be applied to any type of cue. We add to the cross-linguistic literature on this matter by comparing normalization accounts against a new phonetically annotated vowel database of Swedish, a language with a particularly dense vowel inventory of 21 vowels differing in quality and quantity. We evaluate normalization accounts on how they differ in predicted consequences for perception. The results indicate that the best performing accounts either center or standardize formants by talker. The study also suggests that general purpose accounts perform as well as vowel-specific accounts, and that vowel normalization operates in both temporal and spectral domains.

Individual variability in subcortical neural encoding shapes phonetic cue weighting

Recent studies have revealed great individual variability in cue weighting, and such variation is shown to be systematic across individuals and linked to differences in some general cognitive mechanism. The present study investigated the role of subcortical encoding as a source of individual variability in cue weighting by focusing on English listeners’ frequency following responses to the tense/lax English vowel contrast varying in spectral and durational cues. Listeners differed in early auditory encoding with some encoding the spectral cue more veridically than the durational one, while others exhibited the reverse pattern. These differences in cue encoding further correlate with behavioral variability in cue weighting, suggesting that specificity in cue encoding across individuals modulates how cues are weighted in downstream processes.

Word-level prosodic and metrical influences on Hawaiian glottal stop realization.

Previous research on the phonetic realization of Hawaiian glottal stops has shown that it can be produced several ways, including with creaky voice, full closure, or modal voice. This study investigates whether the realization is conditioned by word-level prosodic or metrical factors, which would be consistent with research demonstrating that segmental distribution and phonetic realization can be sensitive to word-internal structure. At the same time, it has also been shown that prosodic prominence, such as syllable stress, can affect phonetic realization. Data come from the 1970s-80s radio program Ka Leo Hawai'i. Using Parker Jones' (Parker Jones, Oiwi. 2010. A computational phonology and morphology of Hawaiian. University of Oxford DPhil. thesis) computational prosodic grammar, words were parsed and glottal stops were automatically coded for word position, syllable stress, and prosodic word position. The frequency of the word containing the glottal stop was also calculated. Results show that full glottal closures are more likely at the beginning of a prosodic word, especially in word-medial position. Glottal stops with full closure in lexical word initial position are more likely in lower frequency words. The findings for Hawaiian glottal stop suggest that prosodic prominence does not condition a stronger realization, but rather, the role of the prosodic word is similar to other languages exhibiting phonetic cues to word-level prosodic structure.

ACOUSTICALLY-DRIVEN PHONEME REMOVAL THAT PRESERVES VOCAL AFFECT CUES.

In this paper, we propose a method for removing linguistic information from speech for the purpose of isolating paralinguistic indicators of affect. The immediate utility of this method lies in clinical tests of sensitivity to vocal affect that are not confounded by language, which is impaired in a variety of clinical populations. The method is based on simultaneous recordings of speech audio and electroglotto-graphic (EGG) signals. The speech audio signal is used to estimate the average vocal tract filter response and amplitude envelop. The EGG signal supplies a direct correlate of voice source activity that is mostly independent of phonetic articulation. These signals are used to create a third signal designed to capture as much paralinguistic information from the vocal production system as possible-maximizing the retention of bioacoustic cues to affect-while eliminating phonetic cues to verbal meaning. To evaluate the success of this method, we studied the perception of corresponding speech audio and transformed EGG signals in an affect rating experiment with online listeners. The results show a high degree of similarity in the perceived affect of matched signals, indicating that our method is effective.

Penultimate lengthening in isiNdebele: A system and its variations

Lengthening of the penultimate syllable in a word, phrase, or utterance is common across Bantu languages, especially in Eastern and Southern Bantu languages. Despite the prevalence of the general phenomenon, there is significant cross-linguistic diversity in how PUL is instantiated. The aim of this paper is to describe the PUL patterns and variation in isiNdebele, a Nguni language spoken in South Africa. IsiNdebele is closely related to Zulu and frequently spoken in situations of intense contact with Zulu, but its realisation of penultimate lengthening nevertheless shows important differences from what has been reported for Zulu and other Nguni languages. In addition, penultimate lengthening in isiNdebele shows significant internal variation, both across speakers and across utterances produced by the same speaker. This variation has implications for both phonological and syntactic analyses of this language: Many studies of phonological phrasing in other Nguni languages use penultimate length as the main phonetic cue for phrase boundaries, but a strict correlation between PUL and phrasing cannot be confirmed for isiNdebele. Lengthening also depends on factors such as speech rate, emphasis, and careful vs. casual speech.

Investigating the Effects of Speaker Variability on Arabic children’s Acquisition of English Vowels

This study investigated whether speaker variability in phonetic training benefits vowel learnability by Arabic learners of English. Perception training using High-Variability stimuli in laboratory studies has been shown to improve both the perception and production of Second Language sounds in adults and children and has become the dominant methodology for investigating issues in Second Language acquisition. Less consideration is given to production training, in which Second Language learners focus on the role of the articulators in producing second language sounds. This study aimed to assess the role of speaker variability by comparing the effect of using High-Variability and Low-Variability stimuli for production training in a classroom setting. Forty-six Arabic children aged 9-12 years were trained on 18 Standard Southern British English vowels in five training sessions over two weeks and were tested before and after training on their vowel production and category discrimination. The results indicate that Low-Variability stimuli may be more beneficial for children, however, High-Variability stimuli may alter some phonetic cues. Furthermore, the results suggest that production training may be used to improve the perception and production of Second Language sounds, but also to inform the design of Second Language pronunciation learning programmes and theories of Second Language acquisition.