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The purpose of this study was to determine the threshold of velopharyngeal coupling area at which listeners switch from identifying a consonant as a stop to a nasal in North American English, based on V1CV2 stimuli generated with a speech production model that encodes phonetic segments as relative acoustic targets. Each V1CV2 was synthesized with a set of velopharyngeal coupling functions whose area ranged from 0 to 0.1 cm2. Results show that consonants were identified by listeners as a stop when the coupling area was less than 0.035–0.057 cm2, depending on place of articulation and final vowel. The smallest coupling area (0.035 cm2) at which the stop-to-nasal switch occurred was found for an alveolar consonant in the /ɑCi/ context, whereas the largest (0.057 cm2) was for a bilabial in /ɑCɑ/. For each stimulus, the balance of oral versus nasal acoustic energy was characterized by the peak nasalance during the consonant. Stimuli with peak nasalance below 40% were mostly identified by listeners as stops, whereas those above 40% were identified as nasals. This study was intended to be a precursor to further investigations using the same model but scaled to represent the developing speech production system of male and female talkers.

Summary Objectives To determine the effects of Invisalign® aligners on patients’ abilities to articulate consonants. Materials and methods Thirty patients undergoing active two-arch Invisalign® treatment were examined. Patients were recorded reading the rainbow passage (a passage with every phoneme represented), once with the trays inserted and once with the trays removed. The recordings were analysed by a speech pathologist for misarticulation of consonant phonemes. Results Misarticulation of consonants was significantly associated with the Invisalign® aligners inserted as based on the McNemar's statistical test (P = 0.008). The fricative alveolar consonant /z/ was found to be the most impacted by the trays, followed by the consonant /s/ (P = 0.016). The consonant /sh/ was not shown to be affected by the Invisalign® aligners. Conclusions Invisalign® aligners do have an impact on the articulation of consonants. Fricative alveolar consonants were the primary phonemes impacted. Due to the fact that the efficacy of Invisalign® treatment is based primarily on compliance and that speech impairment may interfere with compliance, the information presented in this study should be conveyed to the patient before the initiation of Invisalign® treatment.

Place of articulation plays an important part to produce different sounds. Besides the place of articulation, tongue is also an active articulator during a continuous speech. During the speech, the tongue moves around creating different sounds when it is placed at different place of articulation. The movement of tongue is controlled by muscles. The lack of muscle movement will produce inactive tongue movement. Paralysis is an example of the muscle weakness in a person resulting in difficulties to move. Paralysis may occur due to several factors including stroke and spinal cord injury (SCI). One of the indirect effects of paralysis is slurred speech and difficulty in speaking. This study aims to determine the contact pattern of five paralysed subjects during speech production of alveolar consonants in the Malay Language. The subjects had paralysis due to different aetiologies and with different medical history backgrounds. All participants were required to produce five single consonants; /d/, /t/, /l/, /n/ and /s/. The data recording was done in a studio laboratory with a soundproof system. The device used for detecting the tongue and hard palate contact in this study was electropalatography (EPG). Subjects were required to wear the artificial palate consists of 62 sensors to detect the tongue and hard palate contact. The speech contact was analysed using Articulate Assistant 1.18TM. The results were then compared with the average contact pattern of Malay speaker which had been obtained in the previous study. In conclusion, the subjects who had frequent treatments produced better articulation and the subjects with positive attitudes produced better articulation during the treatment process.

This paper describes a wearable intraoral system for speech therapy using artificial sensory feedback timed with the undesired tongue movement. The system has been implemented as a custom-made palatal retainer, which includes two optical distance sensors and two stimulators to provide error feedback to the tongue. Subjects wore the palatal retainer to test the system performance. By testing the system with phonetic targets /t/ and /d/, we showed that the system was able to detect the tongue movement during pronunciation. The system was also tested to see if it can help a non-native English speaker with Hindi mother tongue to correct the pronunciation of alveolar consonant /t/. The subject was asked to read multiple words containing /t/ consonant repeatedly, with distracting words in between to minimize the involvement of cognition or intentional correction. Test results indicated that the error feedback via stimulation helped the subject to move his tongue forward towards the alveolar ridge in pronouncing /t/. The result justified our hypothesis that intrinsic sensory feedback can be an effective way to train non-native speakers to correct their pronunciation.

A nasal consonant is the part of the manner of articulation in the Malay language. Nasal consonant consisting of bilabial consonant /m/, alveolar consonant /n/, postalveolar consonant /ŋ/ and velar consonant /ŋ/. This paper presents the study of the contact pattern in the production of consonant /m/ using Electropalatography. Nine Malay speakers involved in this study. In detecting the contact pattern during the production of consonant /m/, Reading palate, which consists of 62 electrodes were used. The data were analyzed using Articulate Assist TM Version 1.18. The result indicates that during the production of consonant /m/ there was more contact at the posterior of the hard palate compared to other zones of the palate. Additionally, the Molar Class of the subjects does not affect the pattern production of consonant /m/.

The purpose of this paper is to provide a formal analysis of word-initial consonant-glide (CG) sequences in English loanword adaptation in Korean, within the framework of Optimality Theory (OT; Prince and Smolensky 1993, McCarthy and Prince 1995). The process brings some challenging aspects in that an alveolar consonant and labial-velar glide (/tw/) sequence induces vowel-epenthesis in loanword adaptation, while the other CG sequences are perfectly acceptable in both loanwords and native words in Korean, The discrepancy of /tw/ sequences in loanwords and native words has been accounted for by perceptional and acoustic experiments in many works. This study exhibits the asymmetric behavior between English /tw-/ and /kw-/ with respect to vowel epenthesis found in loanwords in Korean can best be formalized by postulating fixed input for loan phonology from the perceptual basis without any special constraints and ranking only for loan phonology.

Although raising the sides of the tongue to form a seal with the palate and upper teeth – lateral bracing – plays a key role in controlling airflow direction, providing overall tongue stability and building up oral pressure during alveolar consonant production, details of this articulatory gesture remain poorly understood. This study examined the dynamics of lateral bracing during the onset of alveolar stops /t/, /d/, /n/ produced by15 typical English-speaking adults using electropalatography. Percent tongue palate contact in the lateral regions over a 150-ms period from the preceding schwa to stop closure was measured. Rapid rising of the sides of the tongue from the back towards the front during the 50-ms period before closure was observed, with oral stops showing significantly more contact than nasal stops. This feature corresponds to well-documented formant transitions detectable from acoustic analysis. Possible explanations for increased contact for oral stops and clinical implications are di...

Lateral consonants are complex and variable sounds. Static MRI provides relevant information regarding /l/ geometry, but does not address dynamic properties. Real-time MRI is a well suited technique for dealing with temporal aspects. However, large amounts of data have to be processed to harness its full potential. The main goal of this paper is to extend a recently proposed quantitative framework to the analysis of real-time MRI data for European Portuguese /l/. Several vocal tract configurations of the alveolar consonant, acquired in different syllable positions and vocalic contexts, were compared. The quantitative framework revealed itself capable of dealing with the data for the /l/, allowing a systematic analysis of the multiple realisations. The results regarding syllable position effects and coarticulation of /l/ with adjacent vowels are in line with previous findings.

This investigation seeks to understand the factors causing vocalization and elision of dark /l/ in the Romance languages. Contrary to articulatory-and perceptual-based arguments in the literature it is claimed that preconsonantal vocalization conveys the phonemic categorization of the /w/-like formant transitions generated by the tongue dorsum retraction gesture (in a similar fashion to other processes such as /Vji/ > /Vjn/). The evolution /VwlC/ > /VwC/ may be explained using articulatory and perceptual arguments. A dissimilatory perceptual mechanism is required in order to account for a much higher frequency of vocalizations before dentals and alveolars than before labials and velars in the Romance languages. Through this process listeners assign the gravity property of dark /l/ to a following grave labial or velar consonant but not so to a following acute dental or alveolar consonant in spite of the alveolar lateral being equally dark (i.e., grave) in the three consonantal environments. Other articulatory facts appear to play a role in the vocalization of final /l/ (i.e., the occurrence of closure after voicing has ceased) and of geminate /ll/ (i.e., its being darker than non-geminate /l/). The elision of dark /l/ may occur preconsonantally and word finally either after vocalization has applied or not. This study illustrates the multiple causal factors and the articulatory-perceptual nature of sound change processes.

This paper presents the speech recognition of Malay Alveolar consonants of Malay children using neural networks in a speaker-independent manner. The Alveolar consonants consist of /d/, /t/, /l/, /r/, /s/, /z/ and /n/. The Alveolar consonants are combined with six Malay vowels to form the consonant-vowel (CV) syllable sounds. 100 children are involved in the speech recording with a total of 4200 speech sounds. The speech sounds are recorded at a sampling rate of 20 KHz with 16-bit resolution. Linear Predictive Coding (LPC) is used to extract the speech feature extraction. Multi-layer Perceptron (MLP), which is one of the most popular neural networks, is used to classify the Alveolar consonants. Experiments are conducted to determine the optimal signal length of the consonants, and hidden neuron number of MLP. A maximum recognition rate of 62.14% is obtained at signal lengths of 150ms and 160ms.

Relatively little work has examined acoustic‐phonetic variability in consonants in infant‐directed speech, particularly that directed to children with hearing loss. Assimilation is a form of variability which has been particularly well studied in adult‐directed speech in which a word‐final alveolar consonant takes the place of articulation of a following word‐initial consonant (as when /n/ in cotton sounds like /m/ in the phrase cotton[m] balls). Two studies examined types of acoustic‐phonetic variation in assimilable environments, defined as contexts in which a word‐final alveolar stop (oral or nasal) is adjacent to a word‐initial labial or velar consonant, in speech directed to adults and to infants with and without hearing loss. First, waveform, spectral, and perceptual information were used to classify tokens of word‐final alveolar stops into four categories: assimilated, canonical, glottalized, or deleted. Next, the second formant, F2, was measured in a subset of these tokens, to gauge the extent of ...

In German (and many languages) the alveolar nasal /n/ can assimilate to [m] if followed by a labial (e.g. 'in Berlin' ← "i[m] Berlin"). In a German spontaneous speech corpus (KielCorpus), one also finds a few cases in which an /m/ followed by an alveolar consonant surfaces as [n] (e.g., 'samstag' ← "sa[n]stag", Engl. Saturday). Four experiments investigated whether there is a similar pre‐lexical compensation process for these labial‐to‐alveolar assimilations as previous research uncovered for alveolar‐to‐labial assimilations. This turns out to be the case: German and Dutch listeners‐the latter potentially unfamiliar with this type of assimilation‐tend to perceive the assimilated [n] in "sanstag" as /n/ if presented in isolation ("an"), but as /m/ if presented with minimal context ("ansta"). For German listeners, this context effect is larger if they hear the complete word "sanstag", introducing an additional lexical bias to perceive the [n] as /m/. Finally, phonetic detail such as transitions of the [s] fricative pole are also important: If the assimilated "an" is spliced into another /s/‐initial syllable by the same speaker, the context effect is reduced. Perceiving infrequent assimilations seems therefore similar to perceiving frequent assimilations.

Japanese mora nasal /N/ and more obstruent /Q/ have no definite point of articulation. For instance, /N/ becomes [m] when a bilabial consonant follows and [n] when an alveolar consonant follows. /Q/ is also realized as [p], [t], or [k], depending on the point of articulation of the following consonant. Four native speakers of Japanese produced /N/ and /Q/ in /CVNCV/ and /CVQCV/ contexts, where the consonant after /N/ and /Q/ is always a stop. Their utterances were recorded and digitized. The word final /CV/ was edited out, and the stimuli with the structure of /CVN/ and /CVQ/ were created. Twelve native speakers of Japanese and American English were recruited as listeners in Shiga, Japan and Auburn, AL, respectively. The American listeners were told to identify the word final consonant in a multiple‐choice format. The Japanese listeners were told that they were to tell whether /Q/ and /N/ were realized as [m], [n], [■], and [p], [t], [k], respectively. The American listeners outperformed the Japanese listeners despite the fact that they had had no prior exposure to Japanese. This is probably because a stop does not occur or no phonemic contrast is allowed in a postvocalic position in Japanese.

An articulatory study of the scope of prosodic boundary effects across boundaries of varying strengths is presented. Sentences in each of three prosodic conditions contain the following string: C1VC2VC3♯VC4VC5VC6, where C is an alveolar consonant, V is a vowel, and ♯ is a prosodic boundary. The boundaries are of three degrees of strength. Using articulator movement‐tracking data (EMA) for the tongue tip articulator, consonant constriction formation and release duration, acceleration duration, and spatial magnitude are measured. Leftward and rightward temporal effects of the boundary on the consonants are investigated. Based on earlier studies (e.g. Cambier‐Langeveld, Linguistics in the Netherlands, 13–24, 1997; Shattuck‐Hufnagel and Turk, Proceedings 16th International congress on Acoustics and 135th Meeting Acoustical Society of America, 1235–1236, 1998; Berkovits, J. of Phonetics 21, 479–489, 1993) and predictions of the prosodic gestural model (Byrd and Saltzman, J. of Phonetics, 31, 149–180, 2003), it...

The duration of a consonant is potentially affected by various factors related to the phonetic nature of the segment and its phonetic environment. The present study addresses the concurrent effects of prominence, syllable structure, and manner of articulation in intervocalic /s/+alveolar consonant /t, n, l/, and alveolar consonant+/s/ clusters in Swedish. Six real words, imbedded in a carrier sentence, were repeated five times with, and five times without, focal accent by ten native speakers of standard Swedish. Results show that the duration of a cluster, and the duration of its constituent consonants, are longer with focal accent than without focal accent. Consonant clusters with /s/ as the first member do not differ in duration from consonant clusters with /s/ as the second member. Clusters containing an alveolar stop are shorter than clusters with an alveolar nasal or alveolar liquid. The duration of /s/ is always longer than the duration of any adjacent alveolar stop, nasal or liquid. A number of interactions was found between prominence, cluster structure, and manner of articulation, indicating clear differences between the patterns of cluster internal timing for the investigated cluster pairs. These differences will be presented, compared with data on American English, and discussed.

The focus of this study is individual differences in tongue kinematics in the production of sequences of vowel–stop consonant–vowel. Four subjects produced VCV sequences with all possible combinations of the vowels /i, a, u/, and the stop consonants /p, t, k, b, d, g/. A magnetometer system was used to track vertical and horizontal movements of receivers placed on four points on the tongue. Individual variations were found for the influences of stop consonant voicing and vowel quality on tongue kinematics. In addition, in sequences with an alveolar consonant /t, d/ occurring between two high vowels /i, u/, some speakers lowered the rear portions of the tongue for the consonant closure, while other subjects maintained a tongue configuration that closely resembled that for the high flanking vowels. Possible accounts for these differences, such as oral anatomy, speaking rate, and speaking style will be discussed, as well as the acoustical consequences of the different articulatory patterns. [Work supported b...

Experimental dental prostheses having 4 mm of thickness in the alveolar region were supplied to 10 subjects. Data on tongue/palate contacts and jaw motions taken at the time of first attempting to speak with the prosthesis, and after 2 weeks of adaptation, are discussed. There was palatographic evidence for tongue overshoot on /s, z, t, d, n/ when first speaking with the prosthesis. Some subjects also showed minor changes in place of articulation, both initially and as a compensatory adjustments after adaptation. Jaw adjustments were characterized by an overall translation of activity to a more open or more closed set, with the phonetic contextual subtleties of jaw activity largely preserved. Anticipatory coarticulation with a following open vowel was found for /1/, but this was disturbed in some subjects when first speaking with the prosthesis. Variability of articulation was no greater when initially speaking with a prosthesis than after adaptation. Data are interpreted to suggest that adaptation proceeds according to a compensatory strategy.

Coordination between intrinsic and jaw‐related components of tongue blade movement during the articulation of the alveolar consonant /t/ was examined across changes in phonetic context. Tongue–jaw interactions included compensatory responses of one articulatory component to a contextual effect on the position of the other articulatory component. A similar reciprocity has been observed in studies that introduced artificial perturbation of jaw position and studies of patterns of token‐to‐token variability. Thus the lingual–mandibular complex seems to respond in a similar manner to at least some natural and artificial perturbations.

Previous results suggest that anticipatory lip rounding appears to precede the onset of a rounded vowel by a constant temporal duration and hence, that the effect of rounding on preceding alveolar consonant strings may be better described in terms of temporal proximity to the vowel than in terms of the spreading of temporal features. An extension of this general principle suggests the hypothesis that consonant strings should be acoustically less affected by the identity of preceding or following vowel segments as the duration of the string increases. In order to test the hypothesis, production of semantically anomalous sentences containing words with either the vowel /i/ or /u/, and with /s/, /st/, or /st‐st/ between the two vowels (e.g., “leased stool,” etc.) were measured, using a spectral display program. Preliminary measurements suggest effects of surrounding vowels on /s/ friction in all these consonant string types, but differences in the magnitude of the effect depending on consonant string duration. [Work supported by NINCDS and BRSG.]

Data obtained by a computer‐controlled x‐ray microbeam system are being analyzed [Kiritani et al., J. Acoust. Soc. Am. 57, 1516–1520 (1975)] in the form of predicting the movements of three pellets located along the tongue surface, and three other pellets located on the velum, the jaw, and the lower lip. The analyzed data include a set of isolated words and sentences spoken by two native speakers of American English. This communication describes the rules necessary for reconstructing with accuracy the position of the six pellets during the sequence /Cae(N)C/, where C represents an alveolar consonant. The high intraspeaker consistency makes it feasible to predict, for each speaker, the behavior of each of the pellets. The large interspeaker differences result in a set of speaker dependent rules. For example, the jaw pellet position and the tongue pellet position (located at about 1 cm behind the tongue tip) for an alveolar consonant depends mainly on the feature “tense‐lax,” for one speaker, and on the syllabic position of the alveolar consonant for the second speaker. The rules governing the articulators not directly involved in the production of the alveolar consonants generally show large interspeaker differences.

Fowler [Phonetica (1981); J. Exp. Psychol. (1983)] has proposed that speech production is a series of global articulatory movements associated with the vowels of an utterance, upon which smaller, consonantal movements are superimposed. A possible articulatory test of this theory models consonants and vowels as alternations between a relatively closed and open vocal tract. Using the Wisconsin x‐ray microbeam system, articulatory records were obtained of English phrases with varied accent placement and alveolar consonant sequences of varied duration. Analysis of one speaker's productions is now complete. When the data are pooled over all conditions, the total duration of the bisyllabic sequence and the time difference between sonority peaks is strongly related to the length of the medial consonants; there is no evidence for articulatory overlap—i.e., vowel shortening in the neighborhood of long consonants or shifting of sonority peaks toward longer consonants. However, correlations within accent types uncover a strong shortening effect for accented syllables preceding long consonants, along with a reduced displacement in the following vowel. Thus any comprehensive overlapping consonant‐vowel theory of speech production must take into account the general prosodic structure of the utterance. [Work supported by the National Science Foundation under grant No. IRI‐8617852 to Mary Beckman.]

In a previous paper [M. Laferriere and O. Fujimura, J. Acoust. Soc. Am. Suppl. 1 70, S13 (1981)], movements of the tongue in the production of medial /t/ and /d/ were discussed using x‐ray microbeam data. It was found that stops generally involve tongue‐body fronting and blade/tip raising, whereas flaps involve only blade/tip raising; and that, for stops, stress of surrounding vowels determines the extent of dynamic tongue‐body gesture. The present study examined stop and flap production in terms of tongue blade displacement, duration and velocity of transition into the consonant, and stress status of surrounding vowels. It was found that (1) peak velocity of tongue blade displacement increased as the amount of displacement increased, and (2) the tenseness of the stressed vowel following the alveolar consonant affected the degree of tongue blade displacement when the preceding vowel was unstressed.