Formant Frequency Fluctuation as an Index of Motor Steadiness in the Vocal Tract

1983 ◽  
Vol 26 (2) ◽  
pp. 297-304 ◽  
Author(s):  
Bruce R. Gerratt
Keyword(s):  
Vocal Tract ◽  
Involuntary Movement ◽  
Predictive Coding ◽  
Normal Subjects ◽  
Acoustic Method ◽  
Frequency Fluctuation ◽  
Linear Predictive Coding ◽  
Vowel Production ◽  
Formant Frequency ◽  
Second Formant

Involuntary movement of the articulatory structures can interfere with the accurate placement of the articulators during consonant production and may also result in distortion of vowel quality. An acoustic method was used to assess motor steadiness in the vocal tract musculature superior to the glottis during vowel production by five subjects with abnormal involuntary orofacial movements associated with tardive dyskinesia and 10 normal subjects. A linear predictive coding technique of spectral analysis yielded formant frequencies from the sustained productions of//. Based on the premise that changes in vocal tract configuration can be measured as changes in formant frequency, the sequential segment-to-segment fluctuations of the second formant frequency of these vowel samples were computed and used as an index of motor steadiness. Results showed that formant frequency fluctuation measures for four of the five tardive dyskinetic patients were substantially larger than those of the normal subjects, indicating a reduction of motor steadiness in these four subjects. Factors influencing the validity of this procedure and implications for its use are discussed.

scholarly journals Variation of Formant Frequency with Nepalese Vowels

2020 ◽  
pp. 16-21
Author(s):  
S.K. Adhikari
Keyword(s):  
Vocal Tract ◽  
Free Field ◽  
Predictive Coding ◽  
Initial Position ◽  
Frequency Range ◽  
Linear Predictive Coding ◽  
Formant Frequency ◽  
Formant Frequencies ◽  
Speech Spectrum ◽  
Shape And Size

The regions of speech spectrum in which the frequency corresponds to relatively large amplitude are known as formants. For any vocalic sounds, number of formants may occur in the frequency range 0 to 4000 Hz. The formant frequencies of speech sounds are directly depending up on the shape and size of vocal tract. The aim of study was to study the variation of formant frequency with Nepalese vowels. Ten Nepalese vowels word in initial position /VC/ as spoken three times by 10 male and 10 female Nepali speakers were recorded in system in the free field of partially acoustically treated room. PRRAT software is used to digitize and analyze the data. Linear predictive coding (LPC) spectra were obtained for each of vowels and formant frequencies were measured. By plotting curve between formant frequencies and vowels, explain their variation.  

Estimation of vocal tract steadiness in speakers of Mandarin-accented English

2009 ◽  
Vol 39 (2) ◽  
pp. 189-204 ◽  
Author(s):  
Yang Chen
Keyword(s):  
Vocal Tract ◽  
Vowel Production ◽  
Formant Frequency ◽  
Gender Dimorphism ◽  
English Vowels ◽  
L2 Learning ◽  
Probable Outcome ◽  
Accented English ◽  
Second Formant ◽  
Brain Reorganization

Vocal tract steadiness reflected by measurement of fluctuation of the second formant frequency is reported for vowel production of Mandarin-accented English (MAE). Fluctuations of the second formant frequency for the 11 English vowels (/i ɪ e ɛ æ ʌ u ʊ o ɔ ɑ/) were examined in the syllable-level productions of 40 Mandarin speakers compared to 40 American English (AE) speakers. Results of the comparative analysis indicate that the pattern of vocal tract steadiness of MAE speakers is generally different in comparison to AE speakers. The discrepancy of vocal tract steadiness between MAE and AE speakers are interpreted as the probable outcome of brain reorganization in adult L2 learning. In addition, discussions of likely gender dimorphism in brain reorganization in L2 learning are provided in view of the opposite patterns of vocal tract steadiness demonstrated by MAE females and males, in comparison to their AE counterparts.

Effects of Long-Term Tracheostomy on Spectral Characteristics of Vowel Production

1991 ◽  
Vol 34 (5) ◽  
pp. 1057-1065 ◽  
Author(s):  
Ruth Saletsky Kamen ◽  
Ben C. Watson
Keyword(s):  
Vocal Tract ◽  
Spectral Characteristics ◽  
Group Differences ◽  
Vowel Production ◽  
Formant Frequency ◽  
Motor Patterns ◽  
Spectral Parameters ◽  
Oral Motor ◽  
Vowel Space

This study investigated the effects of long-term tracheostomy on the development of speech. Eight children who underwent tracheotomy during the prelingual period were compared to matched controls on selected spectral parameters of the speech acoustic signal and standard measures of oral-motor, phonologic, and articulatory proficiency. Analysis of formant frequency values revealed significant between-group differences. Children with histories of long-term tracheostomy showed reduced acoustic vowel space, as defined by group formant frequency values. This suggests that these children were limited in their ability to produce extreme vocal tract configurations for vowels /a,i,u/ postdecannulation. Oral motor patterns were less mature, and sound substitutions were not only more variable for this group, but also reflected a persistent overlay of maladaptive compensations developed during cannulation.

Vocal Tract Steadiness

1992 ◽  
Vol 35 (4) ◽  
pp. 761-768 ◽  
Author(s):  
Petra Zwirner ◽  
Gary J. Barnes
Keyword(s):  
Motor Control ◽  
Fundamental Frequency ◽  
Vocal Tract ◽  
Upper Airway ◽  
Normal Subjects ◽  
Subject Group ◽  
Formant Frequency ◽  
Control Subjects ◽  
Acoustic Analyses ◽  
The Relationship

Acoustic analyses of upper airway and phonatory stability were conducted on samples of sustained phonation to evaluate the relation between laryngeal and articulomotor stability for 31 patients with dysarthria and 12 non-dysarthric control subjects. Significantly higher values were found for the variability in fundamental frequency and formant frequency of patients who have Huntington’s disease compared with normal subjects and patients with Parkinson’s disease. No significant correlations were found between formant frequency variability and the variability of the fundamental frequency for any subject group. These findings are discussed as they pertain to the relationship between phonatory and upper airway subsystems and the evaluation of vocal tract motor control impairments in dysarthria.

In Situ Chatter Frequency Prediction Using Torque Data From a Wireless Sensor Integrated Tool Holder

2009 ◽  
Author(s):  
Christopher A. Suprock ◽  
Robert B. Jerard ◽  
Barry K. Fussell
Keyword(s):  
Real Time ◽  
End Milling ◽  
Predictive Coding ◽  
Wireless Sensor ◽  
Linear Predictive Coding ◽  
Formant Frequency ◽  
Tool Holder ◽  
Milling Tool ◽  
High Bandwidth

A method is demonstrated to estimate chatter frequencies in real time from cutting torque data using formant frequency tracking. Formant frequencies are derived from the torque data using linear predictive coding (LPC) methods, similar to algorithms used in speech recognition. The estimated frequency response is observed to change throughout a cut as a function of both engagement and cut geometry. Torque data is collected at high bandwidth from a wireless sensor integrated end milling tool holder. The technique is found to be effective and repeatable for forecasting regenerative chatter frequencies in real time. Chatter frequencies predicted during non-chatter conditions correctly estimate the actual chatter condition. To demonstrate the technique, a number of experimental cuts are conducted and discussed.

Epenthetic Vowels and Phonemic Vowels: Same or Different?

2020 ◽  
Vol 5 (5) ◽  
pp. 1339-1346
Author(s):  
Christina Akbari ◽  
Katsura Aoyama
Keyword(s):  
Second Language ◽  
Acoustic Signal ◽  
Vocal Tract ◽  
Predictive Coding ◽  
Linear Predictive Coding ◽  
Acoustic Characteristics ◽  
Second Language Speakers ◽  
The Mean ◽  
Double Cluster ◽  
Target Words

Purpose This study was designed to further investigate epenthetic vowels produced by Persian second language speakers of English. Specifically, the purpose was to compare epenthetic and phonemic vowels to determine if acoustic differences existed or if the epenthetic vowels were quantitative “copies” of their phonemic counterparts. Method Twenty Persian speakers each produced 120 target words. The target words were composed of two different double cluster compositions (obstruent + glide and obstruent + liquid) as well as obstruent + liquid triple clusters and obstruent + glide triple cluster combinations. The target words occurred in a phonetic environment that was either preceded by a consonant /t/ or occurred in isolation. This resulted in 2400 tokens. The tokens underwent Linear Predictive Coding to determine the F1 and F2 formant measurements as well as the durations of the epenthetic and phonemic vowels. Formants are the resonance of the vocal tract. F1 is the lowest-frequency formant while F2 is the next highest ( Kent & Read, 2002 ). Linear Predictive Coding allows for the acoustic signal to be represented spectrally for analysis. Results A total of 236 epenthetic voamp'wels and their phonemic counterparts were acoustically analyzed. The phonemic vowels were found to be significantly longer than the epenthetic vowels. The epenthetic vowels were also found to have significantly lower F1 values. As a group, the mean F2 values were not significantly different from the F2 values of the phonemic vowels. However, significant differences in F2 values were found when specific vowel comparisons were made. Conclusions The data indicate that prothetic epenthetic vowels are not copies of the phonemic vowels that they precede. They differ quantitatively in terms of durations, F1, and F2 values. The findings of this study coincide with the findings of other researchers concerning the acoustic characteristics of anaptyctic epenthetic vowels. These results indicate similarities between prothetic and anaptyctic epenthetic vowels.

Interspeaker Variability in Hard Palate Morphology and Vowel Production

2013 ◽  
Vol 56 (6) ◽  
pp. 1924-1933 ◽  
Author(s):  
Adam Lammert ◽  
Michael Proctor ◽  
Shrikanth Narayanan
Keyword(s):  
Hard Palate ◽  
Vocal Tract ◽  
American English ◽  
Imaging Data ◽  
Magnetic Resonance Imaging Data ◽  
Vowel Production ◽  
Formant Frequency ◽  
Acoustical Properties ◽  
Formant Frequencies ◽  
Acoustic Impact

Purpose Differences in vocal tract morphology have the potential to explain interspeaker variability in speech production. The potential acoustic impact of hard palate shape was examined in simulation, in addition to the interplay among morphology, articulation, and acoustics in real vowel production data. Method High-front vowel production from 5 speakers of American English was examined using midsagittal real-time magnetic resonance imaging data with synchronized audio. Relationships among hard palate morphology, tongue shaping, and formant frequencies were analyzed. Simulations were performed to determine the acoustical properties of vocal tracts whose area functions are altered according to prominent hard palate variations. Results Simulations revealed that altering the height and position of the palatal dome alters formant frequencies. Examinations of real speech data showed that palatal morphology is not significantly correlated with any formant frequency but is correlated with major aspects of lingual articulation. Conclusion Certain differences in hard palate morphology can substantially affect vowel acoustics, but those effects are not noticeable in real speech. Speakers adapt their lingual articulation to accommodate palate shape differences with the potential to substantially affect formant frequencies, while ignoring palate shape differences with relatively little acoustic impact, lending support for acoustic goals of vowel production.

scholarly journals Optimizing Vowel Formant Measurements in Four Acoustic Analysis Systems for Diverse Speaker Groups

2016 ◽  
Vol 25 (3) ◽  
pp. 335-354 ◽  
Author(s):  
Ekaterini Derdemezis ◽  
Houri K. Vorperian ◽  
Ray D. Kent ◽  
Marios Fourakis ◽  
Emily L. Reinicke ◽  
...  
Keyword(s):  
Acoustic Analysis ◽  
Predictive Coding ◽  
Linear Predictive Coding ◽  
Formant Frequency ◽  
Male And Female ◽  
Consensus Analysis ◽  
Optimal Analysis ◽  
Software Packages ◽  
Vowel Formant ◽  
Female Children

Purpose This study systematically assessed the effects of select linear predictive coding (LPC) analysis parameter manipulations on vowel formant measurements for diverse speaker groups using 4 trademarked Speech Acoustic Analysis Software Packages (SAASPs): CSL, Praat, TF32, and WaveSurfer. Method Productions of 4 words containing the corner vowels were recorded from 4 speaker groups with typical development (male and female adults and male and female children) and 4 speaker groups with Down syndrome (male and female adults and male and female children). Formant frequencies were determined from manual measurements using a consensus analysis procedure to establish formant reference values, and from the 4 SAASPs (using both the default analysis parameters and with adjustments or manipulations to select parameters). Smaller differences between values obtained from the SAASPs and the consensus analysis implied more optimal analysis parameter settings. Results Manipulations of default analysis parameters in CSL, Praat, and TF32 yielded more accurate formant measurements, though the benefit was not uniform across speaker groups and formants. In WaveSurfer, manipulations did not improve formant measurements. Conclusions The effects of analysis parameter manipulations on accuracy of formant-frequency measurements varied by SAASP, speaker group, and formant. The information from this study helps to guide clinical and research applications of SAASPs.

scholarly journals A Phonetic Level Analysis of Dysarthria in Kannada Language

2020 ◽  
Vol 9 (1) ◽  
pp. 1235-1241
Keyword(s):  
Speech Intelligibility ◽  
Vocal Tract ◽  
Normal Subjects ◽  
Speech Disorders ◽  
Human Beings ◽  
Formant Frequency ◽  
Motor Speech ◽  
Acoustic Characteristics ◽  
Motor Speech Disorder ◽  
Kannada Language

Dysarthria is a motor speech disorder and the most common neurodegenerative disease characterized by low volume in precise articulation, poor coordination of respiratory and phonatory subsystems, irregular pauses and so on. The challenging factor in improving the communication with dysarthria is speech intelligibility. The intelligilibility of speech can be determined by measuring the acoustic characteristics and phonetic structures of speech. In our analysis, we have concentrated on bisyllabic words in the Kannada language. The analysis is carried out with respect to basic acoustic parameters and spectrogram to extract fundamental frequency, formant frequency, jitter, shimmer, HNR and Standard Deviation using PRAAT tool. These results are helpful to identify and differentiate the complex natural frequency of the vocal tract functions with respect to normal subjects and dysarthria subjects. This study provides inputs to increase efficacy in the clinical assessments for monitoring and diagnosing the speech disorders for improving communication among human beings.

scholarly journals Real-Time Vocal Tract Modelling

2007 ◽  
Vol 2007 ◽  
pp. 1-8
Author(s):  
A. Benkrid ◽  
A. Benallal ◽  
K. Benkrid
Keyword(s):  
Transmission Line ◽  
Wave Scattering ◽  
Speech Synthesis ◽  
Vocal Tract ◽  
Predictive Coding ◽  
Realistic Model ◽  
Three Dimensions ◽  
Linear Predictive Coding ◽  
One Dimensional ◽  
Established Technique

To date, most speech synthesis techniques have relied upon the representation of the vocal tract by some form of filter, a typical example being linear predictive coding (LPC). This paper describes the development of a physiologically realistic model of the vocal tract using the well-established technique of transmission line modelling (TLM). This technique is based on the principle of wave scattering at transmission line segment boundaries and may be used in one, two, or three dimensions. This work uses this technique to model the vocal tract using a one-dimensional transmission line. A six-port scattering node is applied in the region separating the pharyngeal, oral, and the nasal parts of the vocal tract.

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