Consonant Syllables Research Articles

Characteristics of Nasal Coarticulation by Nasality Visualization System in Children with Speech Sound Disorders

Objectives: In this study, we analyzed the nasal coarticulation characteristics of children with and without speech sound disorders by comparing nasalance scores according to speech contexts. Methods: The subjects of this study were 30 children, 15 children with speech sound disorder (SSD) and 15 typically developing (TD) children, aged 4 to 6 years old. Subjects were asked to speak stimuli in different speech contexts-low vs. high vowels, nasal consonant+vowel (NV) vs. vowel+nasal consonant (VN) syllables, words vs. nonwords - and nasalance scores were measured using the Nasality Visualization System (NVS) on their speech samples. Results: First, both groups showed significantly higher naslance scores for high vowels compared to low vowels, with a significant between-group difference in high vowel. Second, both groups showed significantly higher nasalance scores for VN syllables than for NV syllables, with no between-group difference. Third, both groups showed significantly lower nasalance scores in nonwords compared to words. While there was no group difference in the words, the nasalance scores of the SSD group was lower in the nonwords, which was significantly different from that of the TD groups. Conclusion: These results suggest that the SSD group exhibits somewhat different nasal characteristics than the TD group, and furthermore, that SSD children articulate phoneme sequences more segmentally in unlearned nonword contexts.

Gemination and Degemination before the Feminine Sound Plural Suffix in Native and Loanwords in Arabic

This study aimed to explore the gemination of consonants preceding the Feminine Plural suffix /-a:t/ in native and loanwords in Arabic, which consonants are geminated and when they are degeminated before /a:t/, to compare the conditions under which geminated and ungeminated consonants occur before /a:t/; and to define the relationship between the vowels preceding geminate and singleton consonants in syllables before /a:t/. A sample of 70 loanwords and 70 native Arabic nouns and/or adjectives having a Feminine Sound Plural (FSP) form with geminated and degeminated consonants before the suffix /a:t/ was collected from some websites. Data analysis showed that the FSP formation of both native and loanwords in Arabic follows the same Arabic pluralization rules. When a stem ends in a singleton consonant, the feminine plural suffix /a:t/ is directly added in لمسات /lamasa:t/ touches & درونات /dro:na:t/ drones. Almost all types of consonants can be geminated in word-final position in Arabic. In this case, the suffix /a:t/ is directly added to form FSP as in فلزّات /filizza:t/ metals & لمات /lamma:t/ gatherings. But when the stem ends with a vowel following the geminated consonant, the vowel is deleted as Arabic does not allow the sequence of two vowels (مودات /mawadda:t/ affections). The stops /p, b, k, g/, fricatives /f, ʃ, tʃ, dʒ/ and graphemes {ll}; {lla}, {ette} are geminated in some loan stems before the plural suffix /a:t/ as in كليبات /klippa:t/ clips; تريلات /trilla+a:t/ trailers; بروفات /proof+a:t/ professors; تاتشات /tatʃtʃ+a:t/ touches; مانشيتات /manʃitt+a:t/ manchettes (headlines). In 48% of the loanwords in the sample, the final consonant of the stem is not geminated before /a:t/ ماركت) /ma:rkita:t/ markets( due to the long vowel in a preceding syllable. In loanwords where the stem is feminine singular ending in /a/, this vowel is deleted before /a:t/ as in صالات /Sala:t/ salles; كاميرات /kamira:t/ cameras, as it is the case in native Arabic words with stems ending in /a/. No gemination takes place before /a:t/ as there is a long vowel in a preceding syllable. The study concludes with recommendation for language and translation pedagogy and for future research.

The influence of phoneme contexts on adaptation in vowel‐evoked envelope following responses

Repeated stimulus presentation leads to neural adaptation and consequent amplitude reduction in vowel‐evoked envelope following responses (EFRs)—a response that reflects neural activity phase‐locked to envelope periodicity. EFRs are elicited by vowels presented in isolation or in the context of other phonemes such as consonants in syllables. While context phonemes could exert some forward influence on vowel‐evoked EFRs, they may reduce the degree of adaptation. Here, we evaluated whether the properties of context phonemes between consecutive vowel stimuli influence adaptation. EFRs were elicited by the low‐frequency first formant (resolved harmonics) and middle‐to‐high‐frequency second and higher formants (unresolved harmonics) of a male‐spoken /i/ when the presence, number and predictability of context phonemes (/s/, /a/, /∫/ and /u/) between vowel repetitions varied. Monitored over four iterations of /i/, adaptation was evident only for EFRs elicited by the unresolved harmonics. EFRs elicited by the unresolved harmonics decreased in amplitude by ~16–20 nV (10%–17%) after the first presentation of /i/ and remained stable thereafter. EFR adaptation was reduced by the presence of a context phoneme, but the reduction did not change with their number or predictability. The presence of a context phoneme, however, attenuated EFRs by a degree similar to that caused by adaptation (~21–23 nV). Such a trade‐off in the short‐ and long‐term influence of context phonemes suggests that the benefit of interleaving EFR‐eliciting vowels with other context phonemes depends on whether the use of consonant‐vowel syllables is critical to improve the validity of EFR applications.

Phonetics exercises using the Alvin experiment-control software.

Exercises are described that were designed to provide practice in phonetic transcription for students taking an introductory phonetics course. The goal was to allow instructors to offload much of the drill that would otherwise need to be covered in class or handled with paper-and-pencil tasks using text rather than speech as input. The exercises were developed using Alvin, a general-purpose software package for experiment design and control. The simplest exercises help students learn sound-symbol associations. For example, a vowel-transcription exercise presents listeners with consonant-vowel-consonant syllables on each trial; students are asked to choose among buttons labeled with phonetic symbols for 12 vowels. Several word-transcription exercises are included in which students hear a word and are asked to enter a phonetic transcription. Immediate feedback is provided for all of the exercises. An explanation of the methods that are used to create exercises is provided. Although no formal evaluation was conducted, comments on course evaluations suggest that most students found the exercises to be useful. Exercises were developed for use in an introductory phonetics course. The exercises can be used in their current form, they can be modified to suit individual needs, or new exercises can be developed.

Audio-visual speech experience with age influences perceived audio-visual asynchrony in speech

Previous research indicates that perception of audio-visual (AV) synchrony changes in adulthood. Possible explanations for these age differences include a decline in hearing acuity, a decline in cognitive processing speed, and increased experience with AV binding. The current study aims to isolate the effect of AV experience by comparing synchrony judgments from 20 young adults (20 to 30 yrs) and 20 normal-hearing middle-aged adults (50 to 60 yrs), an age range for which a decline of cognitive processing speed is expected to be minimal. When presented with AV stop consonant syllables with asynchronies ranging from 440 ms audio-lead to 440 ms visual-lead, middle-aged adults showed significantly less tolerance for audio-lead than young adults. Middle-aged adults also showed a greater shift in their point of subjective simultaneity than young adults. Natural audio-lead asynchronies are arguably more predictable than natural visual-lead asynchronies, and this predictability may render audio-lead thresholds more prone to experience-related fine-tuning.

The right ear advantage revisited: Speech lateralisation in dichotic listening using consonant–vowel and vowel–consonant syllables

The dichotic listening task is typically administered by presenting a consonant–vowel (CV) syllable to each ear and asking the participant to report the syllable heard most clearly. The results tend to show more reports of the right ear syllable than of the left ear syllable, an effect called the right ear advantage (REA). The REA is assumed to be due to the crossing over of auditory fibres and the processing of language stimuli being lateralised to left temporal areas. However, the tendency for most dichotic listening experiments to use only CV syllable stimuli limits the extent to which the conclusions can be generalised to also apply to other speech phonemes. The current study re-examines the REA in dichotic listening by using both CV and vowel–consonant (VC) syllables and combinations thereof. Results showed a replication of the REA response pattern for both CV and VC syllables, thus indicating that the general assumption of left-side localisation of processing can be applied for both types of stimuli. Further, on trials where a CV is presented in one ear and a VC is presented in the other ear, the CV is selected more often than the VC, indicating that these phonemes have an acoustic or processing advantage.

Phonological Processing in Human Auditory Cortical Fields

We used population-based cortical-surface analysis of functional magnetic imaging data to characterize the processing of consonant–vowel–consonant syllables (CVCs) and spectrally matched amplitude-modulated noise bursts (AMNBs) in human auditory cortex as subjects attended to auditory or visual stimuli in an intermodal selective attention paradigm. Average auditory cortical field (ACF) locations were defined using tonotopic mapping in a previous study. Activations in auditory cortex were defined by two stimulus-preference gradients: (1) Medial belt ACFs preferred AMNBs and lateral belt and parabelt fields preferred CVCs. This preference extended into core ACFs with medial regions of primary auditory cortex (A1) and the rostral field preferring AMNBs and lateral regions preferring CVCs. (2) Anterior ACFs showed smaller activations but more clearly defined stimulus preferences than did posterior ACFs. Stimulus preference gradients were unaffected by auditory attention suggesting that ACF preferences reflect the automatic processing of different spectrotemporal sound features.

Influence of perceptual training of syllable codas for English consonants on sentences.

This study extends our previous report suggesting that moderate amounts of speech perception training were associated with improved speech production. This study also examined perception in sentences. A new group of 8 Spanish speakers (<10 year residence in US) trained on 13 English final consonants in syllables using SPATS software. On days 1 and 7 the group participated in perception and production tasks with the 13 codas (pre‐ and post‐tests). Perception tests included coda identification in both syllable stimuli and in 18 sentences extracted from the IEEE corpus (90 keywords). Results showed the following. (1)With 5‐h training of the 13 codas in syllable stimuli, perception improved significantly (>10%) in the syllable post‐test, with smaller improvement in the sentence post‐test (>7%). (2) Although average improvement was small for codas tested in sentences, several improved substantially (>20%), while a few decreased considerably after perception training. (3) Absolute values in both post‐tests show similar performance, near 90%, although interesting differences for specific consonants were noted. The results showed that perception of sounds when measured in different linguistic contexts (syllables versus sentences) rendered different results. The study lays ground for investigating how cross‐language perception of individual sounds is influenced by the phonetic context.

Perceptual learning of co-articulation in speech

Four experiments investigated the novel issue of learning to accommodate the co-articulated nature of speech. Experiment 1 established a co-articulatory mismatch effect for a set of vowel–consonant (VC) syllables (reaction times were faster for co-articulation matching than for mismatching stimuli). A rhyme judgment training task on words (Experiment 2) or VC stimuli (Experiment 3) with mismatching information was followed by a phoneme monitoring task on a set of VC stimuli; training and test stimuli contained physically identical (same condition) or new (different condition) mismatching co-articulatory information (along with a set containing matching co-articulatory information). A third group received no training. A co-articulatory mismatch effect was found without training but not when the same mismatching tokens were used at training and test. Both word (Experiment 2) and syllable (Experiment 3) training stimuli eliminated the mismatch effect; overall reaction times were somewhat slower when the training stimuli were words. Perceptual learning generalized to new tokens only when the acoustic manifestation of the critical co-articulatory information in the training stimuli was sufficiently large (Experiments 3 and 4). The results are discussed in terms of speech processing and perceptual learning in speech perception.

Allophonic and Phonemic Contrasts in Infants' Learning of Sound Patterns

French-learning 11-month-old and English-learning 11- and 4-month-old infants were familiarized with consonant–vowel–consonant syllables in which the final consonants were dependent on whether the preceding vowel was oral or nasal. Oral and nasal vowels are present in the ambient language of all participants, but vowel nasality is phonemic (contrastive) in French and allophonic (noncontrastive) in English. After familiarization, infants heard novel syllables that either followed or violated the familiarized patterns. French-learning 11-month-olds and English-learning 4-month-olds displayed a reliable pattern of preference demonstrating learning and generalization of the patterns, while English-learning 11-month-olds oriented equally to syllables following and violating the familiarized patterns. The results are consistent with an experience-driven reduction of attention to allophonic contrasts by as early as 11 months, which influences phonotactic learning.

Brainstem encoding of voiced consonant–vowel stop syllables

Objective The purpose of this study is to expand our understanding of how the human auditory brainstem encodes temporal and spectral acoustic cues in voiced stop consonant–vowel syllables. Methods Auditory evoked potentials measuring activity from the brainstem of 22 normal learning children were recorded to the voiced stop consonant syllables [ga], [da], and [ba]. Spectrotemporal information distinguishing these voiced consonant–vowel syllables is contained within the first few milliseconds of the burst and the formant transition to the vowel. Responses were compared across stimuli with respect to their temporal and spectral content. Results Brainstem response latencies change in a predictable manner in response to systematic alterations in a speech syllable indicating that the distinguishing acoustic cues are represented by neural response timing (synchrony). Spectral analyses of the responses show frequency distribution differences across stimuli (some of which appear to represent acoustic characteristics created by difference tones of the stimulus formants) indicating that neural phase-locking is also important for encoding these acoustic elements. Conclusions Considered within the context of existing knowledge of brainstem encoding of speech–sound structure, these data are the beginning of a comprehensive delineation of how the human auditory brainstem encodes perceptually critical features of speech. Significance The results of this study could be used to determine how neural encoding is disrupted in the clinical populations for whom stop consonants pose particular perceptual challenges (e.g., hearing impaired individuals and poor readers).

Auditory evoked fields differentially encode speech features: an MEG investigation of the P50m and N100m time courses during syllable processing

The functional organization of speech sound processing in the human brain and its unfolding over time are still not well understood. While the N100/N100m is a comparatively well-studied, and quite late, component of the auditory evoked field elicited by speech, earlier processes such as those reflected in the P50m remain to be resolved. Using magnetoencephalography, the present study follows up on previous reports of N100m-centred spatiotemporal encoding of phonological features and coarticulatory processes in the auditory cortex during consonant-vowel syllable perception. Our results indicate that the time course and response strength of the P50m and N100m components of evoked magnetic fields are differentially influenced by mutually exclusive place-of-articulation features of a syllable's stop consonant and vowel segments. Topographical differences in P50m generators were driven by place contrasts between consonants in syllables, with spatial gradients orthogonal to the ones previously reported for N100m. Peak latency results replicated previous findings for the N100m and revealed a reverse pattern for the earlier P50m (shorter latencies depending on the presence of a back vowel [o]). Our findings allow attribution of a role in basic feature extraction to the comparatively early P50m time window. Moreover, the observations substantiate the assumption that the N100m response reflects a more abstract phonological representational stage during speech perception.

Estimation of Transpalatal Nasalance during Production of Voiced Stop Consonants by Noncleft Speakers Using an Oral-Nasal Mask

Our objective was to estimate nasalance due to transpalatal transfer of acoustic energy during production of voiced stop consonants by noncleft speakers. We also determined the relationship between the transpalatal nasalance and fundamental frequency (F0) of the speakers. Participants were 8 men and 10 women (mean age = 21.9 years, SD = 4.0) without cleft palate who produced voiced stop (/b d g/) and nasal (/m n eta/) consonants in syllables embedded in a carrier phrase. Participants also read the Zoo Passage. A divided OroNasal Nasality System mask was used to simultaneously obtain acoustic nasalance and airflow during production of the consonants. Both F0-derived and first formant (F1)-derived nasalance were computed. F0-derived and F1-derived peak nasalance across all speakers ranged from a low of 20% to a high of 80% during production of stop consonants. An estimate of error from the combined sources of transoral transfer of energy (5%) and acoustic crossover between microphones (15%) was no greater than 20%. Analysis of variance revealed no significant effects of the sex of the speakers for either F0-derived or F1-derived nasalance of stops. There was a significant effect of the place of stop production for F0-derived nasalance (p;th< .05). Nonsignificant but positive correlations were found between the F0 of the speakers and F0-derived (r = .25) and F1-derived (r = .45) nasalance. Transpalatal transfer of oral acoustic energy accounts for most nasalance obtained during production of voiced stop consonants by noncleft speakers. F1-derived nasalance appears to better reflect transpalatal effects. Clinical implications are discussed.

Disruption by speech of serial short-term memory: The role of changing-state vowels

Serial short-term memory is markedly impaired by the presence of irrelevant speech so long as the successive tokens within the irrelevant speech are phonologically (or acoustically) dissimilar (Jones & Macken, 1995b). In two experiments in which consonant-vowel-consonant syllables were used as irrelevant speech tokens, we sought to evaluate the relative disruptive potency of changes in the final consonant only (Experiment 1), in the initial consonant, or in the vowel portion (Experiment 2) of each token. The results suggest that the vowel changes are the dominant source of disruption. This dominance may be explained, at least in part, by the role played by vowel sounds in the perceptual organization of speech and, in turn, the particular propensity for vowel changes to yield information about serial order. The results are consistent also with the view that the factors that promote order encoding in sound are also the ones that promote disruption.

Acoustic and perceptual characteristics of vowels produced during simultaneous communication

This study investigated the acoustical and perceptual characteristics of vowels in speech produced during simultaneous communication (SC). Twelve normal hearing, experienced sign language users were recorded under SC and speech alone (SA) conditions speaking a set of sentences containing monosyllabic words designed for measurement of vowel duration, formant frequencies, and fundamental frequency in consonant–vowel–consonant (CVC) syllables and 60 listeners audited the speech samples. Although results indicated longer sentence and vowel durations for SC than SA, the data showed no difference in spectral characteristics of vowels produced during SC versus SA, indicating no degradation of vowel spectrum by rate alteration during SC. Further, no difference was found in listeners’ ability to identify vowels produced during SC versus SA, indicating no degradation of vowel perceptual cues during SC. These conclusions are consistent with previous research indicating that temporal alterations produced by SC do not produce degradation of segmental acoustical characteristics of spoken English. Learning outcomes As a result of this activity, the participant will be able to (1) describe simultaneous communication; (2) explain the role of simultaneous communication in communication with children who are deaf; (3) describe vowel acoustics in English speech; (4) discuss methods of measuring vowel perception; (5) specify the acoustic characteristics of vowels produced during simultaneous communication; and (6) specify the ability of listeners to perceive vowels in speech produced during simultaneous communication.

Infants learn phonotactic regularities from brief auditory experience

Two experiments investigated whether novel phonotactic regularities, not present in English, could be acquired by 16.5-month-old infants from brief auditory experience. Subjects listened to consonant–vowel–consonant syllables in which particular consonants were artificially restricted to either initial or final position (e.g. /bæp/ not /pæb/). In a later head-turn preference test, infants listened longer to new syllables that violated the experimental phonotactic constraints than to new syllables that honored them. Thus, infants rapidly learned phonotactic regularities from brief auditory experience and extended them to unstudied syllables, documenting the sensitivity of the infant's language processing system to abstractions over linguistic experience.

Preservation of second formant transitions during simultaneous communication:: A locus equation perspective

This study investigated the preservation of second formant transition acoustic cues to intelligibility in speech produced during simultaneous communication (SC) from a locus equation perspective. Twelve normal hearing, experienced sign language users were recorded under SC and speech alone (SA) conditions speaking a set of sentences containing monosyllabic words designed for measurement of second formant frequencies in consonant–vowel–consonant (CVC) syllables. Linear regression fits made to coordinates representing second formant transition onset and offset frequencies following stop consonant release of CVC syllables (locus equations) were used to examine place of articulation cues in both SA and SC conditions. Although results indicated longer sentence durations for SC than SA, locus equation slopes and intercepts obtained from speech produced during SC were virtually identical to those obtained during SA, indicating no degradation of stop consonant acoustic cues during SC. This conclusion is consistent with previous research indicating that temporal alterations produced by SC do not involve violations of other rules of spoken English. Educational objectives: As a result of this activity, the participant will be able to (1) describe SC; (2) explain the role of SC in communication with children who are deaf; (3) describe second formant transitions in English speech; and (4) identify second formant transition patterns in speech produced during SC.

Learning phonotactic constraints from brief auditory experience

Three experiments asked whether phonotactic regularities not present in English could be acquired by adult English speakers from brief listening experience. Subjects listened to consonant–vowel–consonant (CVC) syllables displaying restrictions on consonant position. Responses in a later speeded repetition task revealed rapid learning of (a) first-order regularities in which consonants were restricted to particular positions (e.g. [bæp] not *[pæb]), and (b) second-order regularities in which consonant position depended on the adjacent vowel (e.g. [bæp] or [pIb], not *[pæb] or *[bIp]). No evidence of learning was found for second-order regularities in which consonant position depended on speaker's voice. These results demonstrated that phonotactic constraints are rapidly learned from listening experience and that some types of contingencies (consonant–vowel) are more easily learned than others (consonant–voice).

Target spectral, dynamic spectral, and duration cues in infant perception of German vowels.

Previous studies of vowel perception have shown that adult speakers of American English and of North German identify native vowels by exploiting at least three types of acoustic information contained in consonant-vowel-consonant (CVC) syllables: target spectral information reflecting the articulatory target of the vowel, dynamic spectral information reflecting CV- and -VC coarticulation, and duration information. The present study examined the contribution of each of these three types of information to vowel perception in prelingual infants and adults using a discrimination task. Experiment 1 examined German adults' discrimination of four German vowel contrasts (see text), originally produced in /dVt/ syllables, in eight experimental conditions in which the type of vowel information was manipulated. Experiment 2 examined German-learning infants' discrimination of the same vowel contrasts using a comparable procedure. The results show that German adults and German-learning infants appear able to use either dynamic spectral information or target spectral information to discriminate contrasting vowels. With respect to duration information, the removal of this cue selectively affected the discriminability of two of the vowel contrasts for adults. However, for infants, removal of contrastive duration information had a larger effect on the discrimination of all contrasts tested.

Rate-induced resyllabification revisited.

This paper presents the results of a rate scaling speech production experiment which seeks to replicate and examine in greater detail the results of a set of experiments reported in Stetson (1951). Stetson observed, based on a set of pioneering articulatory experiments, that coda consonants resyllabify as onset consonants in syllables repeated at fast speech rates. In the current experiment, speakers produced repetitions of simple CV and VC syllables in time to a metronome pacer which systematically changed in period. Data indicate that, while durational patterns for CV and VC syllables are very different at slow rates, the patterns tend to converge at fast rates. However, closer examination of fast rate tokens, reveals that differences between CV and VC tokens persist at fast rates, even though such tokens are generally heard as CV tokens. These results are discussed with respect to the nature of CV and VC organization and the effect of the rate-changing task.