Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Speech Acoustics”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1985

An acoustic-speech study of patients who received orthognathic surgery.

Several reports have suggested that orthognathic surgery may influence speech patterns. The purpose of this study was to examine the formant frequency changes of speech following orthognathic surgery in patients whose speech was considered perceptually normal preoperatively and postoperatively. Speech samples were obtained from five patients (three patients with Class II, Division 1 malocclusions and two patients with Class III malocclusions). Significant second-formant frequency shifts were found for the vowel 'e' (as in 'seat'); however, only minor second-formant frequency variations were found for the vowels 'a' (as in 'sat') and 'u' (as in 'suit'). The pattern of formant frequencies before and after surgical treatment suggested that the speakers adjusted their articulation to accommodate the orthognathic surgery. Overall, the data from this study indicate that speech patterns may be reorganized after orthognathic surgery even though speech remains perceptually "normal."

Adolescent↗
PubMed2005

Correlation between acoustic speech characteristics and non-speech motor performance in Parkinson Disease.

BACKGROUND: Research has found that non-speech motor deficits in Parkinson Disease (PD) can be consistently improved by levodopa medications and surgical treatment, but that speech and voice are only partially responsive to treatment. This has led to the assertion that speech is an axial (non-peripheral) feature of PD, along with other features that are only partially responsive to treatment (e.g., postural stability and gait). The current study tested this assertion via examination of the relationship between multiple measures of speech production and multiple measures of non-speech movement in individuals with PD. MATERIAL/METHODS: Nine individuals with idiopathic PD were studied, and all participants were taking levodopa-carbidopa medication. Motor performance was examined using the motor portion of the Unified Parkinson's Disease Rating Scale, and speech was examined via acoustic analysis of phonation, articulation, and prosody. RESULTS: Seven of sixteen speech acoustic measures (FoSD in vowels, F2 slope for /u/ and /ae/, FoSD in reading, articulation rate in monologue, and percent pause in reading and monologue) were significantly correlated with non-speech movements. Results suggested that speech measures are correlated with both axial motor symptoms (e.g., gait, facial expression, posture, postural stability) and non-axial motor symptoms (e.g., rest tremor, left and right bradykinesia, postural tremor). CONCLUSIONS: It has been hypothesized that axial symptoms of PD are more purely dopaminergic, and non-axial symptoms are related to non-dopaminergic lesions. Therefore, the current results indicate that certain speech deficits in PD may result from dopaminergic lesions, while others appear to result from non-dopaminergic lesions.

Aged↗
PubMedDate not supplied

[Evaluation of dysarthria with the assistance of acoustic speech analysis in patients with amyotrophic lateral sclerosis].

The aim of the study was to assess dysarthria in ALS subjects using acoustic speech analysis. The study was performed in 47 definite or probable ALS patients aged 29-76 years (mean age 53.7 yr.) and in 30 age and sex matched healthy control subjects. Neurological examination showed 15 dysarthric ALS subjects. Acoustic speech analysis is a quantitative, computer-acoustic method estimating dysarthria and based on assessing of sound distance from speech sound tests. In both group the mean sound distance between chosen sounds was compared to a basic pattern and was measured on time-frequency computer acoustic analyses (delta f = 125 Hz, delta T = 9 ms, delta s = 0.5 dB). Our results demonstrated that all sounds were incorrect in all ALS subjects. These abnormalities were significantly increased in the dysarthric ALS subjects. The mean sound distances which separated ALS from control subjects is 0.2 (by Euclidian principle) in 4 out of 5 measured sounds. We suggest that it is possible to detect and measure dysarthria in ALS patients based on the acoustic speech analysis, also in the limb onset ALS subjects.

Adult↗
PubMed2001

SIM--simultaneous inverse filtering and matching of a glottal flow model for acoustic speech signals.

A new method "simultaneous inverse filtering and model matching" (SIM) is proposed that allows one to calculate voice source measures without any user interaction. It is based on the discrete all-pole modeling (DAP) technique for inverse filtering (IF), which is modified to include a model of the glottal flow as integral part [LF model, Fant et al., STL-QPSR (Stockholm) 4/1985, 1-13 (1986)]. As the correct LF parameters are initially unknown, they are estimated in an iterative procedure using multi-dimensional optimization techniques that are initialized according to the results of an exhaustive search. The error criteria applied reflect how well the IF is performed after the spectral contribution of the glottal flow has been removed. The resulting optimal LF parameter constellation serves as the basis to calculate 11 voice source measures. The performance was evaluated using synthesized signals and recordings of natural utterances. For the synthesized signals, the accuracy to reproduce the original parameters was high (correlations exceeding 0.88) for measures where the starting point of the glottal cycle did not enter explicitly. Errors were smaller compared to conventional estimation methods where the measures were estimated from the IF signal. The analysis of natural utterances indicates that problems still exist with regard to robustness, but that under advantageous conditions the open quotient, the speed quotient, the closing quotient, the parabolic spectral parameter, and the negative peak amplitude of the glottal flow derivative can indeed be determined automatically by the SIM method.

Fourier Analysis↗
PubMed1980

New methods of analysis in speech acoustics.

This paper gives a tutorial review of the linear prediction method in its application to acoustical analysis of sampled speech. The paper explains how the formant frequencies and the fundamental frequency can be estimated from sampled speech waves by the use of linear prediction. Advantages and disadvantages of the method are discussed together with the problems in estimating the above parameters. Application examples are also given.

Adult↗
PubMed2005

Quantifying the effect of compression hearing aid release time on speech acoustics and intelligibility.

Compression hearing aids have the inherent, and often adjustable, feature of release time from compression. Research to date does not provide a consensus on how to choose or set release time. The current study had 2 purposes: (a) a comprehensive evaluation of the acoustic effects of release time for a single-channel compression system in quiet and (b) an evaluation of the relation between the acoustic changes and speech recognition. The release times under study were 12, 100, and 800 ms. All of the stimuli were VC syllables from the Nonsense Syllable Task spoken by a female talker. The stimuli were processed through a hearing aid simulator at 3 input levels. Two acoustic measures were made on individual syllables: the envelope-difference index and CV ratio. These measurements allowed for quantification of the short-term amplitude characteristics of the speech signal and the changes to these amplitude characteristics caused by compression. The acoustic analyses revealed statistically significant effects among the 3 release times. The size of the effect was dependent on characteristics of the phoneme. Twelve listeners with moderate sensorineural hearing loss were tested for their speech recognition for the same stimuli. Although release time for this single-channel, 3:1 compression ratio system did not directly predict overall intelligibility for these nonsense syllables in quiet, the acoustic measurements reflecting the changes due to release time were significant predictors of phoneme recognition. Increased temporal-envelope distortion was predictive of reduced recognition for some individual phonemes, which is consistent with previous research on the importance of relative amplitude as a cue to syllable recognition for some phonemes.

Adult↗
PubMed1990

[Memory and interference resistance of the speech-acoustic system as the indicators of the functional state of the temporal structures in focal epilepsy].

In 99 patients with focal epilepsy, the memory was studied in comparison of melodies and emotions along with the speech-acoustic++ system noise rejection. The degree of these functions impairment was primarily determined by the severity of the brain organic damage and other intra- and extrafocal factors. The impairment of noise rejection could be manifested by its increase or decrease with reference to the normal levels. Memory disorders manifested themselves in facilitated comparison of emotions and especially of melodies with increased delay. Decreased noise rejection and memory disorders were most pronounced in right temporal pathology. Increased noise rejection pathognomonic of the children with cerebral paralysis and left temporal lobe lesion was related to the activation in the mirrored focus.

Adolescent↗
PubMed2005

Preservation of hearing in cochlear implant surgery: advantages of combined electrical and acoustical speech processing.

OBJECTIVES/HYPOTHESIS: This study documents the importance of preserving residual low-frequency acoustic hearing as those with more residual hearing are selected for cochlear implantation. Surgical strategies used for hearing preservation with a short hybrid cochlear implant are outlined. The benefits of preserved residual low-frequency hearing, improved word understanding in noise, and music appreciation are described. STUDY DESIGN: Multicenter, prospective, single-subject design. METHODS: Records were reviewed of 21 individuals participating in an Food and Drug Administration (FDA) feasibility clinical trial who have received an Iowa/Nucleus 10 mm electrode. A second group of subjects receiving implants at the University of Iowa that have used the 10 mm device between 2 years and 6 months were also reviewed. Outcome measures included standardized tests of monosyllabic word understanding, spondees in noise, and common melody recognition. RESULTS: Low-frequency hearing was maintained in all individuals immediately postoperative. One subject lost hearing at 2.5 months postoperative after a viral infection. The group has averaged a loss of -9 dB low-frequency acoustic hearing between 125 and 1,000 Hz. Monosyllabic word understanding scores at 6 months for a group being followed for an FDA clinical trial using the implant plus hearing aids was 69% correct. For the long-term group receiving implants at Iowa, monosyllabic word understanding in those who have used the device between 6 months and 2 years is 79%. Other important findings include improved recognition of speech in noise (9 dB improvement) as compared with standard cochlear implant recipients who were matched for speech recognition in quiet and near normal recognition of common melodies. CONCLUSION: The surgical strategies outlined have been successful in preservation of low-frequency hearing in 96% of individuals. Combined electrical and acoustical speech processing has enabled this group of volunteers to gain improved word understanding as compared with their preoperative hearing with bilateral hearing aids and a group of individuals receiving a standard cochlear implant with similar experience with their device. The improvement of speech in noise and melody recognition is attributed to the ability to distinguish fine pitch differences as the result of preserved residual low-frequency acoustic hearing. Preservation of low-frequency acoustic hearing is important for improving speech in noise and music appreciation for the hearing impaired, both of which are important in real-life situations.

Audiometry, Pure-Tone↗
PubMed1992

Temporal information in speech: acoustic, auditory and linguistic aspects.

The temporal properties of speech appear to play a more important role in linguistic contrasts than has hitherto been appreciated. Therefore, a new framework for describing the acoustic structure of speech based purely on temporal aspects has been developed. From this point of view, speech can be said to be comprised of three main temporal features, based on dominant fluctuation rates: envelope, periodicity, and fine-structure. Each feature has distinct acoustic manifestations, auditory and perceptual correlates, and roles in linguistic contrasts. The applicability of this three-featured temporal system is discussed in relation to hearing-impaired and normal listeners.

Auditory Perception↗
PubMed1991

The identification of nasal obstruction through clinical judgments of hyponasality and nasometric assessment of speech acoustics.

This study examined the records of a consecutive series of 79 patients referred for evaluation at the Oral-Facial and Communicative Disorders Program during a 3-month period in 1989. The purpose was to determine whether clinical judgments of hyponasality, based on a six-point equal-appearing interval scale or an acoustic assessment with a Kay Elemetrics nasometer could provide information concerning nasal airway patency comparable to that obtained by means of aerodynamic measurement techniques. Among the 40 adults in the series, the sensitivity of hyponasality ratings was 0.55 when nasal airway impairment was defined as a condition in which the airway was less than 0.40 and 0.71 when the definition was limited to airways of less than 0.30 cm2. Specificities for the two groups were 0.89 and 0.85, respectively. Similarly, the sensitivity of nasometer ratings was 0.30 for the first group and 0.38 for the second group, while the specificity for the two groups was 0.83 and 0.92, respectively. Comparable analyses for children were not possible because of the extent to which nasal airway size varies in children younger than 15 years of age. Possible reasons for the findings and their clinical significance are discussed.

Adolescent↗
PubMed2001

Emphasis of short-duration acoustic speech cues for cochlear implant users.

A new speech-coding strategy for cochlear implant users, called the transient emphasis spectral maxima (TESM), was developed to aid perception of short-duration transient cues in speech. Speech-perception scores using the TESM strategy were compared to scores using the spectral maxima sound processor (SMSP) strategy in a group of eight adult users of the Nucleus 22 cochlear implant system. Significant improvements in mean speech-perception scores for the group were obtained on CNC open-set monosyllabic word tests in quiet (SMSP: 53.6% TESM: 61.3%, p<0.001), and on MUSL open-set sentence tests in multitalker noise (SMSP: 64.9% TESM: 70.6%, p<0.001). Significant increases were also shown for consonant scores in the word test (SMSP: 75.1% TESM: 80.6%, p<0.001) and for vowel scores in the word test (SMSP: 83.1% TESM: 85.7%, p<0.05). Analysis of consonant perception results from the CNC word tests showed that perception of nasal, stop, and fricative consonant discrimination was most improved. Information transmission analysis indicated that place of articulation was most improved, although improvements were also evident for manner of articulation. The increases in discrimination were shown to be related to improved coding of short-duration acoustic cues, particularly those of low intensity.

Adult↗
PubMed2004

Effect of release time on preferred gain and speech acoustics.

Eighteen experienced hearing aid users with mild to moderate sensorineural hearing loss were fit with a digital hearing instrument. An adaptive procedure was used to determine their preferred gain setting for continuous speech under six conditions. Release time (RT) was set to 40, 160, or 640 msec. A prerecorded speech stimulus was presented in quiet or in the presence of multitalker babble (10 dB signal-to-babble ratio); all other compression variables were fixed. Real-ear data obtained with settings for each condition suggest that RT did not affect gain preference; however, subjects preferred higher gain in the presence of the multitalker babble. The RMS amplitudes of 30 phonemic units were calculated using ear canal recordings of the speech stimulus for each subject in each condition. Altering RT resulted primarily in decreased amplitude with increased RT, but this effect was not predictable across listeners or conditions.

Acoustic Stimulation↗
PubMed1988

[Perception of acoustic speech features with single channel cochlear implants and hearing aids. A comparative analysis].

A newly developed battery of 12 multiple-choice tests for the German language (graded according to difficulty) comprising identification of sentences, words and syllables was applied to 8 patients with single-channel cochlear implants and to 35 deaf hearing-aid users. Phoneme confusion matrices were analysed using sequential information transmission analysis (SINFA) and multi-dimensional scaling (SINDSCAL). Acoustic parameters of the digitally stored test items were compared with the outcome of SINFA and SINDSCAL. It was found that cochlear implant and hearing-aid users relied on the same perceptual dimensions which were correlated to acoustic signal properties of the speech sounds. Best perceived acoustic features were time and amplitude structure of the speech sound (envelope). Fundamental and first formant frequency are evaluated both by implant and hearing-aid users. The use of higher frequency spectral information depends on the amount of residual hearing.

Auditory Threshold↗
PubMed1986

Disturbed coarticulation in apraxia of speech: acoustic evidence.

The results of a recent perceptual study (W. Ziegler & D. von Cramon, 1985, Anticipatory coarticulation in a patient with apraxia of speech. Brain and Language 26, 117-130) provided evidence for disturbed coarticulation in verbal apraxia. Further support for this finding is now provided by acoustic analyses. Formant frequencies and LP reflection coefficients were chosen to assess anticipatory vowel-to-vowel coarticulation and vowel anticipation in stop consonants, respectively. These parameters revealed a lack of coarticulatory cohesion in the speech of a patient suffering from verbal apraxia, explainable by a consistent delay in the initiation of anticipatory vowel gestures. The findings are discussed with respect to prosodic features and to theoretical and clinical concepts of verbal apraxia.

Adult↗
PubMed2003

Interactions of hearing aid compression release time and fitting formula: effects on speech acoustics.

The effects of the interaction of compression release time and prescribed gain on running speech processed through a hearing aid on KEMAR was investigated. A digital instrument was programmed to fit a mild to moderate sloping hearing loss using probe microphone measures to reach targets prescribed by NAL-NL1, DSL I/O, FIG.6 or ASA2p with release times of 40 and 640 ms for each condition. Recordings were made through KEMAR and analyzed to determine the long-term-average-speech spectra, consonant-to-vowel ratios and the RMS amplitude of 32 phonemic units. Aided and unaided results were compared. Within each prescriptive formula, changes in release time affected all of the speech measures subsequent to programming the instrument to a static-composite signal. The short release-time condition produced the greatest alteration to the speech signal. Release time may need consideration when fitting hearing aids to target gain prescriptions.

Acoustics↗
PubMed2001

[Value of acoustic speech analysis for prognostic assessment of stuttering in children. Partial results of a prospective longitudinal study].

UNLABELLED: PRESENT STATE OF KNOWLEDGE: There are currently no known acoustic parameters by which stuttering children can be appraised which will predict their subsequent speech fluency. AIM: To explain the significance of factors which perpetuate stuttering by using computer-based speech analysis of fluent speech for a 1 1/2 year period and to relate acoustic analysis with clinical measurements of stuttering. Special attention was given to motor-oral and/or linguistic deficits. METHOD AND RESULTS: A prospective study of 58 pre-school children who stutter. Correlations were sought between acoustic variables in the severity and course of the stuttering with the influence of motor-oral and linguistic disturbances. 19 age-matched, normal-speaking children served as controls. A subdivision of the study group into different subgroups with particular motor-oral and/or linguistic problems showed that children whose stuttering coincides with a delayed speech development have a distinctly better prognosis for early remission. In most of these children the stuttering remitted to such a degree as the deficits causing the stuttering could be reappraised, which means simultaneous improvement of the linguistic competence. CONCLUSION: It was apparent that remission rate was much higher in those children who showed linguistic disturbances at the same time with stuttering. Within the stuttering group, subgroups showed a few correlations in several acoustic parameters, but these could not, as yet, be shown to give any prognostic markers in the routine diagnosis of children who stutter. If a child shows any danger-signs of acquiring stuttering on a more permanent basis, a careful diagnosis is necessary in order to find the individually underlying factors before any therapeutical procedure.

Child↗
PubMed2001

An exploratory study into perception of acoustic speech cues by hearing-impaired adults.

The aims of the present study were to assess discrimination and identification based on two classes of acoustic cue by adults with acquired sensorineural hearing impairment. Eight hearing-impaired and eight normally hearing adults were asked to identify and discriminate two different sets of speech stimuli. A plosive voicing continuum (coat/goat) varied in voice onset time. The plosive place of articulation continuum (date/gate) varied in burst spectra and second formant transition. Subjects were tested in the unaided condition with the exception of one hearing-impaired subject for whom speech was completely inaudible without a hearing aid. There was no significant between-group difference in discrimination or identification of the voicing contrast. There was no significant between-group difference in identification of stimuli varying by place of articulation. However, three of the eight hearing-impaired subjects were very poor at identification. The hearing-impaired subjects also showed significantly impaired place of articulation discrimination. Both measures were significantly correlated with threshold at 2000 Hz. The results support the view that hearing impairment can have different effects on perception of different acoustic contrasts and on different psychophysical tasks.

Aged↗