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PubMed2006

Analysis of responses to noise in the ventral cochlear nucleus using Wiener kernels.

Responses to noise were recorded in ventral cochlear nucleus (VCN) neurons of anesthetized chinchillas and cats, then analyzed using Wiener-kernel theory. First-order kernels, which are proportional to reverse-correlation functions, of primary-like (PL) and primary-like with notch (PLN) neurons having low characteristic frequency (CF) are similar to those obtained in auditory nerve fibers (ANFs). Such kernels consist of lightly damped transient oscillations with frequency equal to the neuron's CF. The first-order kernel of high-CF PL and PLN neurons displays no evidence of tuning to CF. Second-order kernels of the aforementioned VCN neuron types also resemble those in the nerve, irrespective of CF. In general, first- and second-order Wiener kernels of chopper neurons are similar to those obtained in high-CF ANFs. This is likely the consequence of the poor phase-locking capabilities to near-CF tones exhibited by chopper neurons. By analyzing second-order kernels using singular-value decomposition, it was possible to estimate group delays for the entire neuronal population, regardless of the neuron's type or CF. This was done by analyzing the highest-ranking singular vector (FSV). Amplitude values of FSVs in chopper neurons in the cat are substantially larger than in high-spontaneous ANFs.

Acoustic Stimulation↗
PubMed2006

Electrosonographic characteristics of sounds from temporomandibular joint disc replacement.

The purpose of this study was to investigate the waveform and electrosonographic characteristics of sounds emanating from internal derangement of the temporomandibular joint (TMJ). TMJ sounds were recorded from 10 joints of normal people (NP), 10 joints from patients with anterior disc displacement with reduction (DDR) and 20 joints from patients with anterior disc displacement without reduction (DDNR). The sounds were analyzed through fast Fourier transfer methods to observe their waveforms and electrosonographic characteristics. The observations were then used in differentially diagnosing internal derangement. Wave pattern and electrosonography (ESG) differed among the NP, DDR and DDNR groups. There was very little difference in frequency between the sounds from DDR and DDNR, but the amplitude of the DDR sounds was higher than those of DDNR and NP. The sensitivity and specificity of ESG diagnosis for DDR were 77.2% and 93.3%, respectively, while for DDNR they were 81.6% and 64.7%, respectively.

Adolescent↗
PubMed2005

The neonate cry after cesarean section and vaginal delivery during the first minutes of life.

Although the option for vaginal delivery is most physiological, the achievement of cesarean section is very common in Brazil. The neonate cry represents the beginning of both processes, physiological adaptation and human vocal communication. The cry emission depends on the functioning of respiratory and laryngeal muscles, which are controlled by the nervous system. The acoustic analysis of neonate cry is useful in the assessment of healthy babies and can be used to characterize the signals of diseases through a previously multidisciplinary diagnosis, with immediate medical intervention. The present study compared the acoustic cry characteristics of 30 healthy newborn after a cesarean section and 30 healthy newborn after a vaginal delivery, of both genders, from the exact moment of birth until the first 5 min of life. Using the softwares VOXMETRIA and GRAM, it was possible to analyze the duration, frequency, intensity, occurrence, localization and inspiratory phonation, besides the type of spectrographic tracings. The acoustic cry characteristics of newborns after a C section and a vaginal delivery could evidence not only harmonic, expiratory, acute and strong emissions, but also emissions rich in sounds and varied in types of melody. The differences found can be related to the physiology of birth.

Acoustics↗
PubMed2005

Adaptation of nasometry to Hungarian language and experiences with its clinical application.

OBJECTIVES: (1) To adopt the nasometry for the Hungarian language and to obtain normative nasalance scores. (2) To compare our results with the data of other languages and to evaluate the correlation between nasalance scores and perceptual ratings of nasality. (3) To use the nasometry in various fields of the otolaryngological, phoniatric, and logopedic diagnostics, therapy and documentation. METHODS: (1) To determine the normative nasalance scores regarding the Hungarian language, we included 30 children aged 5-7 years and 45 adults in the 20-25 years age group. In the latter group 15 subjects were speech therapists and 30 phonetically untrained people-15 males and 15 females. STUDY DESIGN: phonation of isolated vowels, articulation of spirants, cyclical repetition of affricates, pronunciation of various (oral, nasal, mixed type) sentences and evaluation of the nasalance score in continuous speech. (2) Thirty-six persons (12 speech pathologists, 12 logopedic students, 12 phonetically uneducated individuals) evaluated the children's physiological and nasal speech recordings with a 3-point scale. (3) Two hundred and forty-eight children of kindergarten age were examined, 20 infants and 6 adult singers in the following fields: evaluation of hypernasality due to cleft palate or velopharyngeal insufficiency (VPI), and of the success of the therapy; examination of hyponasality in cases of enlarged adenoid and allergic rhinitis; evaluation of the speech of hard-of-hearing people; differentiation between nasal sigmatism and hyperrhinophony; testing of the resonance in professional singers; examination of infant cry; application of nasometry in the therapy. RESULTS: The mean value of the nasalance score using the oral sentence: "Zsuzsi kutyája ugat" is 11-13%, in the nasal sentence ("A majom banánt enne") 56%, while that of the mixed sentence representing the Hungarian language ("Jó napot kívánok!") falls in the 30-40% range. The resonance grows with aging and there is no significant difference between genders. The nasalance score is greater with phonetically trained people. Our data correlate with the values of other languages. The correlation is significant between the nasalance scores and perceived nasality (r=0.901). Practical results: Values above 40% in cases of VPI using mixed sentences may support the indication of velopharyngoplasty, together with the subjective evaluation of nasality and other tests. In cases with rhinitis and adenoid vegetation the nasalance score remains below 20%. The nasality value is increased in sensorineural hearing loss, and is decreased in cases with conducting hearing impairment. In nasal sigmatism not the vowels' but the nasality of consonants grow. The difference between the nasalance score of the cry in clefted and non-cleft infants is significant (26% versus 36%): this observation could give possibility in the future to screen babies with congenital hearing problems or hidden VPI. Alterations in nasalance can be documented with nasometry in professional singers when they increase the nasal resonance to grow the power capacity of their voice. The nasometry procedure is a significant help also in speech therapy through the real time visual and auditive control. CONCLUSIONS: The otolaryngological, phoniatric and logopedic diagnostics and therapy is significantly widened with nasometry which is a quick, non-invasive and objective procedure, measuring the nasal resonance of the speech.

Adult↗
PubMed2006

Longitudinal formant analysis after cochlear implantation in school-aged children.

INTRODUCTION: The purpose of this investigation was to describe the correlation between vocal and hearing development by longitudinal analysis of sound spectrograms, as a basic system for evaluating progress in vocal development. SUBJECTS AND METHODS: Two school-aged children with prelingual deafness were evaluated diachronically to assess speech perception and speech intelligibility after cochlear implantation. One child had non-syndromic hearing impairment without any known neurological deficit except for hearing loss, while the other had hearing impairment accompanied by mild mental retardation and attention deficit disorder. Their voices were recorded for monthly follow-up after cochlear implantation; these were used for formant analysis and compared with their mother's voice, and alteration of the formant data was also compared with monosyllable speech perception. RESULTS: Formant analysis demonstrated high concordance was observed between monosyllable speech perception and speech intelligibility. F1-F2 forms of the patients more closely resembled those of their mothers after 1 year's follow-up. The time point at which speech development altered was very similar in both cases although the final outcomes were different. CONCLUSION: Fair improvement of articulation after cochlear implant was demonstrated by the F1-F2 gram analysis. This procedure can be used for data sharing and cooperation between medical and educational specialists.

Child↗
PubMed2005

The effect of fear on paralinguistic aspects of speech in patients with panic disorder with agoraphobia.

The present study investigated the effect of fear on paralinguistic aspects of speech in patients suffering from panic disorder with agoraphobia (N = 25). An experiment was conducted that comprised two modules: Autobiographical Talking and Script Talking. Each module consisted of two emotional conditions: Fearful and Happy. Speech was recorded digitally and analyzed using PRAAT, a computer program designed to extract paralinguistic measures from digitally recorded spoken sound. In addition to subjective fear, several speech characteristics were measured as a reflection of psychophysiology: rate of speech, mean pitch and pitch variability. Results show that in Autobiographical Talking speech was slower, had a lower pitch, and a lower pitch variability than in Script Talking. Pitch variability was lower in Fearful than in Happy speech. The findings indicate that paralinguistic aspects of speech, especially pitch variability, are promising measures to gain information about fear processing during the recollection of autobiographical memories.

Agoraphobia↗
PubMed2005

Three-point bending and acoustic emission study of adult rat femora after immobilization and free remobilization.

The experiment concerned effects of immobilization and remobilization on mechanical properties of femoral shaft. Twenty-four weeks old male rats were used: two groups (I3 and I3R4) with the right hindlimb immobilized for 3 weeks by taping, and one control (C). In I3R4 immobilization was followed by 4 weeks of free remobilization. Mechanical properties in three-point bending, mass, geometry, and mineralization of bone tissue were measured post mortem in both femora in I3 and I3R4 and in right femora in control. Acoustic emission signals (AE) were recorded during the bending test. The right femora in I3, I3R4 and C did not differ significantly in size, mass and mineralization (ANOVA). The differences were significant considering mechanical parameters and AE signals. In I3 yield bending moment and stiffness were lower (p=0.013 and 0.025) and deflection was larger (p=0.030) than in C. In I3R4 maximum bending moment, yield moment, stiffness and work to failure were lower than in C (p=0.013, 0.009, 0.032, and 0.005). Paired t-test showed that remobilization resulted in worsening of properties of right femora. Side-to-side differences in I3R4 were more pronounced than in I3. Moreover, AE signals from the right femora were more numerous and burst type than from the left. The results demonstrate that strength of bone decreases during the first period of free remobilization. The decrease is accompanied by a significant decrease of bone toughness. The AE data support the hypothesis that immobilization-related degradation of bone mechanical properties is associated with increasing brittleness of cortical bone tissue.

Animals↗
PubMed2005

Comparison of acoustic characteristics predicted by Biot's theory and the modified Biot-Attenborough model in cancellous bone.

Biot's theory and the modified Biot-Attenborough (MBA) model are applied to predict the dependences of acoustic characteristics on frequency and on porosity in cancellous bone. The phase velocities and the attenuation coefficients predicted by both theories are compared with the experimental data of bovine cancellous bone specimens published in the literature. Biot's theory successfully predicts the dependences of the phase velocity on frequency and on porosity in cancellous bone, whereas a significant discrepancy is observed between the predicted and the measured attenuation coefficients. The MBA model agrees well with the frequency and the porosity dependences of the phase velocity and the attenuation coefficient experimentally measured in bovine bones. Although the MBA model relies on phenomenological parameters derived from the experimental data, its approach to cancellous bone can be usefully employed in the field of clinical ultrasonic bone assessment.

Acoustics↗
PubMedDate not supplied

Dysarthria associated with traumatic brain injury: speaking rate and emphatic stress.

UNLABELLED: Prosodic abnormality is common in the dysarthria associated with traumatic brain injury (TBI), and adjustments of speaking rate and emphatic stress are often used as steps in treating the speech disorder in patients with TBI-induced dysarthria. However, studies to date do not present a clear and detailed picture of how speaking rate and emphatic stress are affected in this speech disorder. This study, based on the acoustic analyses of syllable repetitions and sentence speech samples, reports on speaking rate and emphatic stress for 12 subjects with TBI and 8 healthy controls. For speaking rate, the subjects with TBI had (1) both slow speaking and articulation rates, (2) smaller phonation proportion and larger pause proportion, and (3) larger percentage change in speaking rate and smaller percentage change in articulation rate. For emphatic stress, the subjects with TBI had (1) significant increases in the difference and percentage change between pre-stressed and pre-unstressed pause durations, (2) significantly smaller difference between stressed and unstressed word durations, but not the percentage change between stressed and unstressed word durations, and (3) significantly reduced differences in f(0) movement and f(0) slope between stressed and unstressed words, but not in RMS range. This study demonstrates the multidimensional nature of prosodic deficits in the dysarthria related to TBI and illustrates the ability of acoustic measures to give a picture of the dysprosody related to TBI-induced dysarthria. LEARNING OUTCOMES: As a result of this activity, the participant will be able to (1) describe the prosodic disturbances that have been reported in studies of dysarthria associated with TBI; (2) define acoustic measures appropriate to the analysis of changes in speaking rate and emphatic stress; and (3) discuss the importance of prosody to spoken communication.

Adolescent↗
PubMed2006

Warming up improves speech production in patients with adult onset myotonic dystrophy.

UNLABELLED: This investigation was conducted to study whether warming up decreases myotonia (muscle stiffness) during speech production or causes adverse effects due to fatigue or exhaustion caused by intensive speech activity in patients with adult onset myotonic dystrophy. Thirty patients with adult onset myotonic dystrophy (MD) and ten healthy controls were examined, using a protocol that requires subjects, to speak continuously for at least 10 min. In MD patients, warming up led to an increase in speech rate and a decrease in speech variability without causing signs of fatigue or exhaustion as a result of prolonged and intensive use of the speech musculature. No significant changes were found in the controls. After warming up, MD patients achieved a habitual speech rate in reading and reciting similar to that of healthy controls. LEARNING OUTCOMES: As a result of this activity the reader will learn that 1. In contrast to most neuromuscular disorders, speech production in patients with adult onset myotonic dystrophy improves by activity. 2. Myotonia in speech musculature in patients with adult onset myotonic dystrophy can be reduced by instructing them to warm up their muscles by repetitive movements. 3. Warming up is a valuable intervention because it improves the velocity and fluency of speech production without aggravating the signs of flaccid dysarthria.

Adolescent↗
PubMed2006

Speech motor development: Integrating muscles, movements, and linguistic units.

UNLABELLED: A fundamental problem for those interested in human communication is to determine how ideas and the various units of language structure are communicated through speaking. The physiological concepts involved in the control of muscle contraction and movement are theoretically distant from the processing levels and units postulated to exist in language production models. A review of the literature on adult speakers suggests that they engage complex, parallel processes involving many units, including sentence, phrase, syllable, and phoneme levels. Infants must develop multilayered interactions among language and motor systems. This discussion describes recent studies of speech motor performance relative to varying linguistic goals during the childhood, teenage, and young adult years. Studies of the developing interactions between speech motor and language systems reveal both qualitative and quantitative differences between the developing and the mature systems. These studies provide an experimental basis for a more comprehensive theoretical account of how mappings between units of language and units of action are formed and how they function. LEARNING OUTCOMES: Readers will be able to: (1) understand the theoretical differences between models of speech motor control and models of language processing, as well as the nature of the concepts used in the two different kinds of models, (2) explain the concept of coarticulation and state why this phenomenon has confounded attempts to determine the role of linguistic units, such as syllables and phonemes, in speech production, (3) describe the development of speech motor performance skills and specify quantitative and qualitative differences between speech motor performance in children and adults, and (4) describe experimental methods that allow scientists to study speech and limb motor control, as well as compare units of action used to study non-speech and speech movements.

Adolescent↗
PubMed2006

Voice onset time for female trained and untrained singers during speech and singing.

UNLABELLED: The purpose of this study was to examine the voice onset times of female trained and untrained singers during spoken and sung tasks. Thirty females were digitally recorded speaking and singing short phrases containing the English stop consonants /p/ and /b/ in the word-initial position. Voice onset time was measured for each phoneme and statistically analyzed. Mixed-ANOVAs revealed significantly longer voice onset time durations during speech for /p/ as compared to sung productions. No significant differences between the trained singers and untrained singers were observed. In addition, no task differences occurred for the /b/ productions. The results indicated that the type of phonatory task influences VOT for voiceless stops in females. LEARNING OUTCOMES: As a result of this activity, the reader will be able to (1) understand articulatory and phonatory differences between spoken and sung productions; (2) understand the articulatory and phonatory timing differences between trained singers and untrained singers during spoken and sung productions.

Adult↗
PubMed2004

Gestural overlap in consonant clusters: effects on the fluent speech of stuttering and non-stuttering subjects.

UNLABELLED: This study was designed to investigate if persons who stutter differ from persons who do not stutter in the coproduction of different types of consonant clusters, as measured in the number of dysfluencies and incorrect speech productions, in speech reaction times and in word durations. Based on the Gestural Phonology Model of Browman and Goldstein, two types of consonant clusters were formed: homorganic and heterorganic clusters, both intra-syllabic (CVCC) and inter-syllabic (CVC#CVC). Overall, the results indicated that homorganic clusters elicited more incorrect speech productions and longer reaction times than the heterorganic clusters, but there was no difference between the homorganic and the heterorganic clusters in the word duration data. Persons who stutter showed a higher percentage dysfluencies and a higher percentage incorrect speech productions than PWNS but there were no main group effects in reaction times and word durations. However, there was a significant three-way interaction effect between group, cluster type and cluster place: homorganic clusters elicited longer reaction times than heterorganic clusters, but only in the inter-syllabic condition and only for persons who stutter. These results suggest that the production of two consonants with the same place of articulation across a syllable boundary puts higher demands on motor planning and/or initiation than producing the same cluster at the end of a syllable, in particular for PWS. The findings are discussed in light of current theories on speech motor control in stuttering. EDUCATIONAL OBJECTIVES: The reader will be able to describe: (1) the effect of gestural overlap between consonant clusters on speech reaction time and word duration of people who do and do not stutter and be able to (2) identify the literature in the field of gestural overlap between consonant clusters.

Adolescent↗
PubMed2005

Opposite effects of short- and long-duration isolation on ultrasonic vocalization, startle and prepulse inhibition in rats.

Housing conditions change the sensorimotor gating and the emotional state of rats. The prepulse inhibition (PPI) is a reduction in the startle reflex to loud sounds when they are preceded by acoustic stimuli of low-intensity, and this test has been considered to be a useful measurement of the functioning of sensory gating in animals and man. Rats reared under conditions of isolation from the time of weaning, but not for 1 week at adult age, display clear deficits in prepulse inhibition and in sensorimotor gating. Ultrasound vocalizations (USVs) at 20-24kHz are the usual defensive responses of rats exposed to threatening conditions such as novel situations. The amount of emissions of ultrasound vocalizations at these frequencies depends on whether the aversive stimuli are presented either alone or in combination. Given this background we evaluated the prepulse inhibition and the emission of ultrasound vocalizations in response to novelty in rats isolated for 1 day or 2 weeks and compared the results to those in grouped rats. We also examined whether the anxiolytic agent midazolam (0.5 and 1.0mg/kg) could reverse the effects of isolation under the experimental conditions used. Rats isolated for 1 day showed a significant increase in the number and duration of USVs together with an enhancement in the startle response to loud sounds, which were antagonized in a dose-dependent manner by midazolam. On the other hand, 2-week isolation had the effect of reducing the number of USVs emitted at 20-24kHz without changing the startle response. The PPI was not changed by isolation, irrespective of the duration of isolation (1 day or 2 weeks). The results suggest that 1 day and 2 weeks of isolation have opposite effects on the emotional state of the animals. While short periods of isolation cause an anxiolytic-sensitive enhancement of the defensive responses, longer periods tend to reduce the defensive reaction of the animals to aversive stimuli. Based on these results, this work presents a novel method for induction of two different modes of defensive response, which are proposed to be mediated by separate neural substrates in rats. Also, isolation from 1 day to 2 weeks has no effect on the expression of prepulse inhibition and, by extension, on the functioning of the sensory gating.

Adaptation, Physiological↗
PubMed2004

Effects of transitory lingual nerve impairment on speech: an acoustic study of diphthong sounds.

PURPOSE: The effects of lingual nerve impairment on the phonetic quality of diphthongs were studied by analyzing changes in their main acoustic features when anesthetic was injected into the lingual nerve to partly block the normal neural feedback mechanisms in speech. PATIENTS AND METHODS: The speech material consisted of 8 diphthongs in word context produced by 7 male speakers. Every utterance was repeated 10 times using normal speech rate and intonation with and without the anesthesia (Ultracain D-Suprarenin, 0.8 mL; Aventis Pharma Deutscland GmpH, Frankfurt am Main, Germany). In addition, 1 male speaker with permanent nerve impairment was studied. The acoustic features (F1, F2, F0, and duration) were analyzed using Computerized Speech Laboratory (CSL 4300B; Kay Elemetrics, Lincoln Park, NJ). RESULTS: At the group level, no general significant acoustic changes were found between the 2 conditions. The changes were highly individual and variable across the subjects. Significant changes were observed for all the subjects, most prominently for the subject with permanent nerve impairment. CONCLUSIONS: According to the results, lingual nerve impairment has effects on the production of diphthongs. A comparison between monophthongs and diphthongs showed that the alterations are more significant for the diphthongs than for other vowels indicating the more demanding, complicated, and complex manner of articulation of diphthongs.

Adult↗
PubMed2006

Acoustic comparison of vowel sounds produced before and after orthognathic surgery for mandibular advancement.

PURPOSE: The effects of orthognathic surgery on the phonetic quality of speech were studied by analyzing the main acoustic features of vowel sounds. PATIENTS AND METHODS: Five men with dentofacial deformities undergoing surgical operation for correction of malocclusion were enrolled in the study. The speech material consisted of 8 vowels in sentence context. Every utterance was repeated 10 times in 3 different sessions: before the operation, 6 weeks after the operation, and 30 weeks after the operation. The acoustic features (F1, F2, F0, duration) of vowels were measured and analyzed. RESULTS: At the group level, no significant acoustic changes were found between the 3 different sessions in any parameter measured (all F values <1). The results show that the operation had individual and variable effects on vowel quality, ranging from slightly affected to completely unaffected. The 2 lowest vocal-tract resonances changed in frequency for 2 of the subjects, and 1 subject had short-term changes returning to the presurgical level. Significant changes of F0 were observed for 1 subject, and 3 of the subjects had short-term changes. No significant changes were found for duration. One subject had no significant changes in any parameter measured. CONCLUSIONS: No long-lasting perceptually significant changes were identified in vowel production in patients undergoing a variety of orthognathic procedures. The facial skeleton (consisting of palate, maxilla, mandible, dentition, nasal cavity, etc) imposes direct limits on the morphology of the resonating vocal tract cavities, and is therefore of immediate relevance to both speech articulation and acoustics.

Adult↗
PubMed2004

Acoustic analysis of voice in multiple sclerosis patients.

The objective is to investigate the presence of dysphonic symptoms in multiple sclerosis (MS) patients and to compare quantitative acoustic parameters in multiple sclerosis patients and normal individuals. The method of study was an 8-month controlled cross-sectional that was carried out with 106 individuals (30 MS, 76 controls). Both groups included males and females from 20 to 55 years. Exclusion criteria were prior vocal disorder, laryngeal microsurgery, recent endotracheal intubation, tumors, laryngeal, lung or mediastinal metastases, respiratory disease, and other associated neurological diagnoses. For dysphonic symptoms (qualitative variables), associations were assessed using Mantel-Haenszel's chi2 test, with Yates correction or the Fisher exact test when necessary. Statistical significance was set at p< or =0.05. Dysphonia was observed in 70% of MS individuals versus 33% of controls (p=0.01). Association was found between MS and dysphonia (OR: 2.2, CI 95%: 1.13-4.25). Fundamental frequency was higher among MS patients (p=0.01). Fundamental frequency deviation was significantly higher in MS women (but not men) than controls (p=0.00). Jitter was higher in MS men than in all other groups (p=0.00). Results suggest that evaluation and treatment of MS patients should be revised, evaluating voice alterations in relation to other signs. MS seems to intensify gender effect on fundamental frequency deviation, noise, and jitter, with MS women presenting fewer voice variations than men.

Adult↗
PubMed2004

Estimating perceived phonatory pressedness in singing from flow glottograms.

The normalized amplitude quotient (NAQ), defined as the ratio between the peak-to-peak amplitude of the flow pulse and the negative peak amplitude of the differentiated flow glottogram and normalized with respect to period time, has been shown to be related to glottal adduction. Glottal adduction, in turn, affects mode of phonation and hence perceived phonatory pressedness. The relationship between NAQ and perceived phonatory pressedness was analyzed in a material collected from a professional female singer and singing teacher who sang a triad pattern in breathy, flow, neutral, and pressed phonation in three different loudness conditions (soft, middle, loud). In addition, she also sang the same triad pattern in four different styles of singing, classical, pop, jazz, and blues, in the same three loudness conditions. A panel of experts rated the degree of perceived phonatory press along visual analogue scales. Comparing the obtained mean rated pressedness ratings with the mean NAQ values for the various triads showed that about 73% of the variation in perceived pressedness could be accounted for by variations of NAQ.

Acoustics↗