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PubMed2006

Adaptation to an electropalatograph palate: acoustic, impressionistic, and perceptual data.

PURPOSE: The purpose of this study was to evaluate adaptation to the electropalatograph (EPG) from the perspective of consonant acoustics, listener perceptions, and speaker ratings. METHOD: Seven adults with typical speech wore an EPG and pseudo-EPG palate over 2 days and produced syllables, read a passage, counted, and rated their adaptation to the palate. Consonant acoustics, listener ratings, and speaker ratings were analyzed. RESULTS: The spectral mean for the burst (/t/) and frication (/s/) was reduced for the first 60-120 min of wearing the pseudo-EPG palate. Temporal features (stop gap, frication, and syllable duration) were unaffected by wearing the pseudo-EPG palate. The EPG palate had a similar effect on consonant acoustics as the pseudo-EPG palate. Expert listener ratings indicated minimal to no change in speech naturalness or distortion from the pseudo-EPG or EPG palate. The sounds [see text] were most likely to be affected. Speaker self-ratings related to oral comfort, speech, tongue movement, appearance, and oral sensation were negatively affected by the presence of the palatal devices. CONCLUSIONS: Speakers detected a substantial difference when wearing a palatal device, but the effects on speech were minimal based on listener ratings. Spectral features of consonants were initially affected, although adaptation occurred. Wearing an EPG or pseudo-EPG palate for approximately 2 hr results in relatively normal-sounding speech with acoustic features similar to a no-palate condition.

Adaptation, Psychological↗
PubMed2001

Acoustic discrimination of pathological voice: sustained vowels versus continuous speech.

We investigated the ability of acoustic measures to discriminate between normal and pathological talkers. Two groups of measures were compared: (a) those extracted from sustained vowels and (b) those based on continuous speech samples. Nine acoustic measures, which include fundamental frequency and amplitude perturbation measures, long term average spectral measures, and glottal noise measures were extracted from both sustained vowel and continuous speech samples. Our experiments were performed on a published database of 53 normal talkers and 175 talkers with a pathological voice. The classification performance of the nine acoustic measures was quantified using linear discriminant analysis and receiver operating characteristic (ROC) curve analysis. When individual measures were considered in isolation, classification was more accurate for measures extracted from sustained vowels than for those based on continuous speech samples. Classification accuracy improved when combinations of acoustic parameters were considered. For such combinations of measures, classification results were comparable for measures extracted from continuous speech samples and for those based on sustained vowels.

Adult↗
PubMed2002

Thresholds of discomfort for complex stimuli: acoustic and sound-quality predictors.

The purpose of this study was to explain differences in threshold of discomfort (TD) across complex stimuli using acoustic and sound-quality variables as predictors. Two 4-tone complexes and 10 environmental sounds were used as stimuli. The environmental sounds consisted of a baby crying, hairdryer blowing, glass breaking, jet engine propelling, person laughing, motorcycle accelerating, orchestra tuning, telephone ringing, siren blowing, and toilet flushing. One-third octave band (1/3 OB) spectra were obtained for the 12 stimuli, with overall rms amplitude held constant across the stimuli. Nine acoustic quantities describing the high- and low-frequency content, peakiness, and bandwidth of each 1/3 OB spectrum were defined. Twenty adult subjects, 6 men and 14 women, with normal hearing sensitivity participated in the study. TDs were obtained from each subject for all of the stimuli. In addition, subjects rated each of the stimuli for annoyance, harshness, loudness, noisiness, and tinniness on a 10-point scale. These ratings were completed at a level 10 dB below each subjects TD for that stimulus. A hierarchical multiple regression analysis was used to estimate the amount of variance in TDs accounted for by subject differences, defined acoustic properties, and sound-quality ratings. Results indicated that, after controlling for intersubject differences, acoustic and sound-quality factors significantly influenced TD ratings. Increases in high-frequency cutoff and low-frequency cutoff, as well as higher ratings of loudness and annoyance, were associated with higher TDs. Associated with lower TDs were an increase in the frequency of the primary spectral peak, an increase in the number of spectral peaks, an increase in the center frequency, an increase in the area under the frequency response curve 30 dB down from the peak amplitude, an increase in the calculated loudness level re ANSI S3.4-1980, and higher ratings of tinniness.

Acoustics↗
PubMed2003

Changes in the human vocal tract due to aging and the acoustic correlates of speech production: a pilot study.

This investigation used a derivation of acoustic reflection (AR) technology to make cross-sectional measurements of changes due to aging in the oral and pharyngeal lumina of male and female speakers. The purpose of the study was to establish preliminary normative data for such changes and to obtain acoustic measurements of changes due to aging in the formant frequencies of selected spoken vowels and their long-term average spectra (LTAS) analysis. Thirty-eight young men and women and 38 elderly men and women were involved in the study. The oral and pharyngeal lumina of the participants were measured with AR technology, and their formant frequencies were analyzed using the Kay Elemetrics Computerized Speech Lab. The findings have delineated specific and similar patterns of aging changes in human vocal tract configurations in speakers of both genders. Namely, the oral cavity length and volume of elderly speakers increased significantly compared to their young cohorts. The total vocal tract volume of elderly speakers also showed a significant increment, whereas the total vocal tract length of elderly speakers did not differ significantly from their young cohorts. Elderly speakers of both genders also showed similar patterns of acoustic changes of speech production, that is, consistent lowering of formant frequencies (especially F1) across selected vowel productions. Although new research models are still needed to succinctly account for the speech acoustic changes of the elderly, especially for their specific patterns of human vocal tract dimensional changes, this study has innovatively applied the noninvasive and cost-effective AR technology to monitor age-related human oral and pharyngeal lumina changes that have direct consequences for speech production.

Adolescent↗
PubMed2003

Acoustic characteristics of the question-statement contrast in severe dysarthria due to cerebral palsy.

Studies of prosodic control in severe dysarthria (DYS) have focused on differences between impaired and nonimpaired speech in terms of the range and variation of fundamental frequency (F0), intensity, and duration. Whether individuals with severe DYS can adequately signal prosodic contrasts and which acoustic cues they use to do so has received far less attention. This article focused on the question-statement contrast. In nonimpaired speech, this contrast is believed to be cued primarily by F0, although some researchers have argued that duration also plays a role. This study examined how 8 speakers with severe DYS due to cerebral palsy signaled the question-statement contrast for a set of 10 short phrases. An additional 8 healthy controls (HCs) produced the same set of phrases as questions and statements. To analyze the speech recordings, peak F0 (F0peak), average F0 (F0ave), slope of F0 (F0slope), peak intensity (INTpeak), average intensity (INTave), slope of intensity (INTslope), and duration measures were calculated for each syllable (S1, S2, S3) within each phrase. Acoustic analyses revealed that speakers with DYS and HCs used F0, duration, and to a lesser degree, intensity cues to signal the contrast. Moreover, productions by speakers with DYS had longer and louder S3 for questions compared to productions by HCs, suggesting that speakers with DYS may have been compensating for their reduced ability to control F0 by exploiting their residual control of loudness and duration. Data from a previous perceptual study (R. Patel, 2002b) with the same speakers with DYS were used to analyze the relationship between acoustic characteristics and listener perceptions of their productions. Logistic regression analysis revealed that S1_F0ave; S2_duration; and S3_duration, S3_F0peak, S3_F0slope, S3_INTave, and S3_ INTslope were significant predictors of the perceived prosodic contrast. Identifying acoustic consistencies in prosodic control among speakers with DYS provides the impetus to build vocalization recognition algorithms that are capable of processing dysarthric speech for use in assistive communication aids. These findings suggest that speakers with DYS may also benefit from intervention aimed at improving prosodic control such that these contrasts may be exploited for communication.

Adult↗
PubMed1977

Clinical acoustic reflex threshold measurements in infants.

Acoustic reflex thresholds elicited using clinical acoustic impedance techniques were obtained on normal infants between one month and one year of age. Reflex activating signals of 500, 1000, 2000 Hz, low-pass, high-pass, and white noise were used. Less intensity was required to elicit the acoustic reflex to the noise than to the pure tones, with the 500-Hz tone requiring the greatest intensity. Inference of auditory thresholds from the acoustic reflex indicated the presence of normal hearing in the infant group.

Acoustic Impedance Tests↗
PubMed1989

Acoustic tracking of articulation errors: [r].

The objective of this study was to determine the usefulness of acoustic tracking as a supplement to perceptual judgements during remediation. One child, receiving weekly individual treatment, participated in a drill-and-practice approach to remediation for a single [w]-for-/r/ substitution error. Imitations of consonant-vowel (CV), VCV, and matched /r/ and /w/ sentence stimuli were audiotape recorded. The temporal and spectral characteristics of the recorded stimuli (i.e., the F2 transition rates and F2 values for the changing [r]) were spectrographically tracked and analyzed over a 70-day remediative period. The acoustic data were compared with the perceptual judgments of articulatory change. Generally, as the child's productions moved from the [w] toward the [r], the measured F2 values became higher and the F2 transition rates lowered. Results suggest that acoustic tracking of a child's productions may become a useful tool to augment perceptual tracking. Implications are discussed for the applications of acoustic tracking within clinical practice.

Articulation Disorders↗
PubMed1980

Acoustic reflex growth in the aging adult.

Growth in amplitude of the acoustic reflex to filtered noise and tones of 500, 1000, and 2000 Hz was measured with an aural acoustic-admittance meter in 30 persons between the ages of 20 and 79 years. Although thresholds of the acoustic reflex did not vary significantly across the age range of the subject sample, the rate of growth in amplitude decreased linearly with increase in age decade. Given information on the aging of structures in the acoustic reflex pathway, the growth data are interpreted tentatively to mean that the contractual capacity of the stapedius muscle is diminished in older ears.

Adult↗
PubMed2000

Acoustic voice analysis by means of the hoarseness diagram.

The hoarseness diagram (Michaelis, Fröhlich, & Strube, 1998a) has been proposed as a new approach to describe different acoustic properties of voices. To test its performance in the analysis of pathologically disturbed and normal voices five requirements are suggested that should be met by any acoustic voice-analysis protocol to be used in voice research and clinical practice. The hoarseness diagram is then tested with regard to these requirements. Individual voices are found to show a satisfactory localization in the diagram. Aspects of stationarity are discussed in the context of four case studies. The different cases illustrate that changes in the acoustic analysis results are observed if the voice-generation conditions change, whereas results are stationary if phonation conditions do not change. Different pathological voice groups defined on grounds of the specific phonation mechanism are found to map to specific regions of the hoarseness diagram, with differences between group locations being significant. All results can be interpreted without exceptions if the two hoarseness diagram coordinates are taken to reflect the vibrational irregularity of the voice-generation mechanisms on the one side and the degree of closure of the vibrating structures on the other side. The hoarseness diagram and its underlying algorithms are thus shown to constitute a useful approach to acoustic voice analysis in research and clinical practice. The tests themselves demonstrate several application possibilities, including the quantitative monitoring of individual voices.

Adolescent↗
PubMed2000

Acoustic differences between content and function words in amyotrophic lateral sclerosis.

Studies describing acoustic characteristics of speech produced by individuals with dysarthria may help to explain intelligibility deficits for these speakers. One goal of the current study was to investigate the manner and extent to which nine speakers with mild to moderate dysarthria associated with amyotrophic lateral sclerosis (ALS) and nine healthy speakers acoustically distinguished /i/, /ae/, /u/, and /a/ in content and function words. A further aim was to evaluate the relationship between impaired speech in ALS and the magnitude of acoustic differences for vowels in content and function words. Speakers read the Farm Passage at a comfortable or habitual rate. F1 and F2 midpoint frequencies were measured, and vowel space areas were calculated. Vowel durations also were measured. The magnitude of F1, F2, vowel space area, and duration differences for vowels in content and function words was not statistically different for speakers with ALS and healthy controls. In addition, with the exception of /i/ produced by some speakers with ALS, vowel duration tended to be shorter in function words. Average F1 and F2 values for function words also tended to be centralized relative to content words. Although vowel space area differences for the two speaker groups were not statistically significant, there was a tendency for the difference in vowel space area for content and function words to be smaller for speakers with ALS than for controls. Regression analyses further indicated that the magnitude of temporal differences for vowels in content and function words was a better predictor of impaired speech than the magnitude of spectral differences for vowels in content and function words. One clinical implication is that individuals with ALS may benefit from therapy techniques targeting temporal properties of the acoustic signal.

Adult↗
PubMed1998

Acoustic rhinometry, rhinomanometry and the amount of nasal secretion in the clinical monitoring of the nasal provocation test.

BACKGROUND: The reliable interpretation of the nasal provocation test in allergy diagnosis requires objective and measurable monitoring parameters for clinical practice. The clinical usefulness of the nasal provocation test has been limited by scanty knowledge of the specificity and sensitivity of the test and a lack of reference values. OBJECTIVE: To test and compare three objective monitoring parameters of a nasal provocation test in occupational allergic rhinitis. To evaluate the magnitude of the nasonasal effects in a unilateral allergen challenge. METHODS: The monitoring parameters of the nasal reaction were derived from the minimum cross-sectional area on acoustic rhinometry, the nasal resistance on active anterior rhinomanometry and the amount of nasal secretion measured at 15 min intervals for 60 min. Twenty-three bovine-allergic dairy and beef cattle farmers and 19 exposed, non-allergic control subjects were challenged first with a control solution and then with the cow allergen. RESULTS: All the three monitoring parameters showed high specificity and sensitivity in finding allergic and non-allergic subjects. The secretion parameter was found to be slightly superior to the acoustic rhinometry and rhinomanometry parameters. The side difference in the nasal response between the allergen-challenged and the contralateral diluent-challenged cavity was significant for all the parameters among the allergic subjects. The contralateral secretion amount was 1/3 of the ipsilateral secretion, indicating the magnitude of the contralateral nasonasal reflex. A nasonasal reflex was also noted in the nasal patency monitoring. The coefficient of variation was significantly lower for the acoustic rhinometry than for the rhinomanometry (P=0.0001). The optimal threshold values for a positive test were a secretion amount of 100 mg, a 15% decrease in the minimum cross-sectional area and a 50% increase in the resistance for the observation period of 30 min and correspondingly 210 mg, 30% and 100% for 60 min. CONCLUSION: The low-pressure aspiration of the nasal secretion from the anterior part of the nasal cavity was found to be a reliable and practical monitoring parameter to be used together with acoustic rhinometry or rhinomanometry in the nasal provocation test for clinical purposes. Although significant nasonasal effects took place in the unilateral allergen challenge, the response was more prominent in the allergen-challenged than in the contralateral diluent-challenged nasal cavity in most allergic subjects.

Acoustics↗
PubMed2002

Left ventricular diastolic dysfunction in congenital chronic anaemias during childhood as determined by comprehensive echocardiographic imaging including acoustic quantification.

AIMS: To evaluate prospectively the left ventricular performance in thalassaemia major and sickle cell disease using comprehensive echocardiographic imaging including acoustic quantification during early childhood. METHODS AND RESULTS: Twenty-three patients with thalassaemia and 26 patients with sickle cell disease underwent echocardiographic examination including M-mode, 2-D, Doppler and acoustic quantification. All patients were matched for age, sex, weight and height with 20 normal controls. All patients were below 13 years of age. Thalassaemia and sickle cell disease patients were significantly anaemic when compared with normals (P<0.0001). All patients had normal left ventricular systolic parameters. Acoustic quantification-derived left ventricular volumes, filling rates, and emptying rates were not different in thalassaemia patients from controls. Left ventricular volumes, however, were larger in sickle cell disease patients than in controls. In contrast, by Doppler technique, left ventricular filling occurs mainly in early diastole (E wave) in thalassaemia patients and mainly in late diastole (A wave) in sickle cell disease patients, (P=0.03 and 0.01 respectively). E/A ratio was lower and diastolic filling period was shorter than normal in sickle cell disease but not in thalassaemia patients. Patients in both groups had left ventricular mass (determined by M-mode) significantly higher than normal (P<0.0001). CONCLUSION: The left ventricular systolic performance is well preserved in patients with chronic anaemia due to thalassaemia major and sickle cell disease during early childhood. In both diseases, however, there is left ventricular hypertrophy and measurable abnormalities in the diastolic filling detected by Doppler. Such changes do not fit a specific cardiomyopathic pattern due to diastolic dysfunction i.e. restrictive physiology vs delayed relaxation. Acoustic quantification of left ventricular diastolic parameters (filling rates) was less sensitive than Doppler in detecting these early diastolic abnormalities in both diseases.

Acoustics↗
PubMed1992

[Evoked otoacoustic emissions and their modification by contralateral acoustic stimulation].

The active vibration of the basilar membrane as well as evoked otoacoustic emissions (EOAE) are probably based on the motile properties of cochlear outer hair cells (OHC). In the present study we examined the effects of contralateral acoustic stimulation on ipsilateral EOAE and thereby the active cochlear micromechanics. Contralateral white noise with intensities below 30 dB HL enhanced the EOAE amplitude, whereas higher sound levels reduced the evoked acoustic emissions. Similar effects of contralateral acoustic stimuli on ipsilateral EOAE were observed in patients with a conductive hearing loss. However, the required sound levels were higher compared to probands with normal hearing. In controls with unilateral deaf patients white noise up to 60 dB HL did not alter the EOAE amplitude. We concluded, that in patients with normal hearing or unilateral conductive hearing loss, effects of contralateral acoustic stimulation on evoked ipsilateral sound emissions may be due to the activation of crossed olivo-cochlear efferents reaching the OHCs.

Acoustic Stimulation↗
PubMed1992

[The acoustics of the open mastoid cavity (so-called "radical cavity") and its modification by surgical measures. II. Clinical studies].

The acoustic resonance of a severely altered outer ear channel (radical mastoid cavity) is investigated in a series of 18 patients who underwent revision surgery by means of in-situ measurements of the sound-pressure-level near the tympanic membrane. While the average volume of the open cavity differs from the normal ear channel for the factor 2.5, the size of the external meatus is--in average--only 20% larger. This leads to an average frequency in patients with open cavity of 1939 Hz, more than 1000 Hz less than in a series (n = 20) of normal ears (average resonance frequency: 2942 Hz). The altered acoustic behaviour of the open cavity leads to partial extensive discrepancies of the resonance-caused sound-pressure augmentation in the frequencies of 3 and 4 kHz, which are important for speech perception. The average difference is more than 10 dB (SPL). Proved surgical techniques of cavity obliteration and meatoplasty can lead to a nearly normalized acoustic behaviour of the outer ear in a statistic significant way. Due to these surgical procedures, an average postoperative resonance frequency of 2421 Hz could be reached in our patients. Especially, the resonance-caused sound-pressure augmentation in 3-4 kHz could nearly be equalized to such of a normal outer ear. Differences in the acoustic behaviour of the outer ear as can be found between patients with an open mastoid cavity and normal ears can almost be eliminated surgically.(ABSTRACT TRUNCATED AT 250 WORDS)

Acoustics↗
PubMed1989

[Analysis of fetal reactions to acoustic stimuli with various registration technics].

The aim of the study was to standardize the types of fetal reactions to a short acoustical stimulation in relation to gestational age and the fetal behavioural state. We used polygraphic monitoring in 74 normal pregnancies to investigate the types of fetal reactions after an acoustical stimulation with a bell or a so-called larynx vibrator. A distinction was made between a very short reaction and a so-called long-term reaction with a long-lasting change in a fetal behavioural pattern. After the 26th gestational week, we observed at the so-called "passive" fetal stage a fetal reaction to the bell in 80% and a reaction to the vibrator in 100%. In the "active" fetal state, there was only a reaction in 54 and 62% of the fetuses respectively. The number of "long-lasting" reactions was relatively increased in the active state and after stimulation with the vibrator. After stimulation with the bell and the vibrator, the actocardiograph tracing showed a heart-rate acceleration in 76% and 61% respectively and a so-called cluster of fetal movements in 88% and 100% respectively. A fetal reaction to acoustical stimulation can be diagnosed most accurately by combining the heart-rate acceleration and the clustering of fetal movements. It still has to be checked to what extent a negative response to acoustical stimulation is indicative of possible fetal distress. In cases with negative tests, further monitoring methods have to be applied in order to exclude fetal hypoxia.

Acoustic Stimulation↗
PubMed2003

Glissando: laryngeal motorics and acoustics.

The objective of this study was to investigate the laryngeal mechanisms and the acoustical signal during a glissando. In particular, glottal length, maximum glottal area, and vibratory amplitudes during a glissando maneuver of a healthy male adult were measured. An endoscopic high-speed system combined with a laser projection device was used to obtain quantitative data both in the time and spatial domains. Simultaneously to the endoscopic investigation, the acoustic signal was recorded. Fundamental frequency and sound pressure level derived from the acoustic recordings were compared to vocal fold length and glottis area derived from the high-speed recordings. Results were used for interpretation of the phonation mechanism during glissando by means of laryngeal and acoustic parameters. The transition between the chest register and the falsetto register was identified by the absence of vocal fold contact. A rather early onset of the falsetto register was observed at 160 Hz. Although fundamental frequency of the vocal folds increased linearly even at the transition point, sound pressure level dropped down. These data represent the first ever quantitative description and interpretation of the glissando based on both voice properties and laryngeal motorics. In the presented example of an untrained singer, the falsetto sets in at comparatively low frequencies. Although the chest-falsetto transition is rather smooth for laryngeal motorics and voice pitch, a sudden drop of voice intensity was observed.

Adult↗
PubMed2000

Disruption of the neural response to rapid acoustic stimuli in dyslexia: evidence from functional MRI.

The biological basis for developmental dyslexia remains unknown. Research has suggested that a fundamental deficit in dyslexia is the inability to process sensory input that enters the nervous system rapidly and that deficits in processing rapid acoustic information are associated with impaired reading. Functional magnetic resonance imaging (fMRI) was used to identify the brain basis of rapid acoustic processing in normal readers and to discover the status of that response in dyslexic readers. Normal readers showed left prefrontal activity in response to rapidly changing, relative to slowly changing, nonlinguistic acoustic stimuli. Dyslexic readers showed no differential left frontal response. Two dyslexic readers participated in a remediation program and showed increased activity in left prefrontal cortex after training. These fMRI results identify left prefrontal regions as normally being sensitive to rapid relative to slow acoustic stimulation, insensitive to the difference between such stimuli in dyslexic readers, and plastic enough in adulthood to develop such differential sensitivity after intensive training.

Acoustic Stimulation↗
PubMed2000

Relationship between cystic change and rotatory vertigo in patients with acoustic neuroma.

Acoustic neuromas are benign neoplasms that most often arise from the vestibular nerve. Many patients with this tumor experience some degree of vestibular symptoms. However, patients rarely complain of rotatory vertigo. Acoustic neuromas are known to exhibit a cystic appearance in some patients. It was hypothesized that cystic change might be a causative factor for rotatory vertigo. A retrospective study of 178 patients with unilateral acoustic neuroma who underwent surgery in the Department of Otolaryngology at Tokyo Medical and Dental University was carried out. The cystic appearance of the tumors was detected preoperatively by magnetic resonance imaging and confirmed at surgery. The relationship between cystic change of the tumor and presentation with rotatory vertigo was examined. Of the 178 patients studied, only 10 had both cystic change of the tumor and rotatory vertigo, and 120 had neither cystic tumor nor rotatory vertigo. Of the remaining 48 patients, 24 experienced rotatory vertigo with negative findings for cystic tumor and the other 24 had evidence of cystic tumor but no rotatory vertigo. Tumor with cystic change was observed in 34 patients, accounting for 19.1% of all patients studied. Rotatory vertigo was also experienced in 34 patients (19.1%). Of the 34 patients with cystic lesions, 29.4% (10) had rotatory vertigo. The difference in percentage of the two groups did not reach statistical significance. It is suggested that there may be other factors causing rotatory vertigo in patients with acoustic neuromas than cystic change of the tumor.

Acute Disease↗