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PubMed2005

Phonotaxis of the female parasitoid Emblemasoma auditrix (Diptera, Sarcophagidae) in relation to number of larvae and age.

The dipteran parasitoid Emblemasoma auditrix locates its host acoustically. Analysis showed that phonotactic female flies usually carry fully developed larvae within their uteri. The mean number of larvae per female at the beginning of the season was 37.9 (range from 10 to 50). The number of larvae decreased rapidly with increasing singing activity of the host cicada (Okanagana rimosa). In high-density host populations the parasitoid is likely to become egg-limited. A possible selective phonotactic responsiveness depending on the number of larvae or the age of the female was tested with song models. Phonotaxis depended on both the temporal structure and the frequency content, but in the field no correlation was found between the number of larvae and the preferences for the acoustic signal. Experiments in the laboratory showed that flies without host contact broadened their phonotactic stimulus range with age.

Acoustic Stimulation↗
PubMedDate not supplied

[Perceptual evaluation of dysphonia: correlation with acoustic parameters and reliability].

The perceptual GRBAS scale for analysis of voice quality is quite important clinically in voices that cannot be effectively analyzed with a voicing parameter method like vocalizations with strong subharmonics and modulations and in chaotic or random voices. In the present study, two experiments were performed: Firstly, GRBAS/acoustical correlations were investigated in 107 pathological voices. Secondly, the GRBAS interrater and intrarater agreement. The severity of dysphonia was assesed better by breath related parameters and low fundamental frequencies. The presence of subharmonics in the power spectrum had not a significant relationship with the degree of roughness. A (asthenic) and S (strain) scales. The results of this study show that GRBAS test-retest reliability and intrerrater agreement is high.

Adult↗
PubMed2005

[Acoustic and aerodynamic characteristics of the oesophageal voice].

OBJECTIVE: The aim of the study is to determine the physiology and pathophisiology of esophageal voice according to objective aerodynamic and acoustic parameters (quantitative and qualitative parameters). MATERIAL AND METHODS: Our subjects were comprised of 33 laryngectomized patients (all male) that underwent aerodynamic, acoustic and perceptual protocol. RESULTS: There is a statistical association between acoustic and aerodynamic qualitative parameters (phonation flow chart type, sound spectrum, perceptual analysis) among quantitative parameters (neoglotic pressure, phonation flow, phonation time, fundamental frequency, maximum intensity sound level, speech rate). CONCLUSION: Nevertheles, not always such observations bring practical resources to clinical practice. We consider that the facts studied may enable us to add, pragmatically, new resources to the more effective vocal rehabilitation to these patients. The physiology of esophageal voice is well understood by the method we have applied, also seeking for rehabilitation, improving oral communication skills in the laryngectomee population.

Aged↗
PubMed2006

[Factors predicting Voice Handicap Index].

OBJECTIVE: To assess factors that may be predictive of patient perception of dysphonia severity, as quantified by the Voice Handicap Index (VHI) score. MATERIAL AND METHODS: A prospective study is carried out in 81 voice samples from patients diagnosed with benign vocal fold lesions. Variables assessed for predictive value to VHI score are maximum fonation time, narrow band spectrogram, jitter, shimmer, HNR, NNE, F0 and the auditory perceptual evaluation of severity of dysphonia GRABS. RESULTS: HNR, F0 and B and S parameters of GRABS were predictors of total VHI score, functional and emotional subscales. No parameter was found to predict the physical subscale. CONCLUSIONS: VHI score is correlated with the perceived breathy voice and its acoustic attributes, such as signal-to-noise ratio. In other studies, patient perception of dysphonia is independent of many factors commonly assessed during the evaluation of voice disorders. It is reasonable to assume that the severity of glottic gap caused by benign vocal folds lesions is related to a low signal-to-noise ratio and the breathy phonation as its perceptual correlate. The physical subscale appears to be an independent element in the assessment of the patient perception of dysphonia.

Adult↗
PubMedDate not supplied

[Comparison of the results obtained through manual and automatic phonetogram].

INTRODUCTION: The phonetogram (F) is the graphic representation of a person phonatory potential. The F carried out with a sonometer and a frequency analyser is what is called "manual phonetogram" (MPh), and the one obtained by means of a computer is called the "automatic phonetogram" (APh). MATERIAL AND METHODS: We have carried out in 12 lyrical singers a standard MPh and an APh with the program Dr. Speech Science 3.0. RESULTS: It was showed a significant difference with a p < 0.0005 in 14 of the 15 measures compared, and a p < 0.05 for the other one, being in general the results of the automatic test different from those of the manual in excess, with a correlation between the results obtained through both methods. CONCLUSIONS: The APh obtained with the program Dr. Speech Science 3.0 is a faster and easier way to obtain the phonetogram than the one used to obtain the MPh, showing however big differences in excess compared with the ones of the MPh in all the usual phonetometric parameters.

Adult↗
PubMed2005

[Dysphonia: current methods of evaluation].

OBJECTIVES: The aim of this review article was to provide an update on current techniques for evaluation of dysphonia in routine clinical practice. MATERIALS AND METHODS: Recent medical and other scientific literature was reviewed and pertinent current theories concerning the physiology of laryngeal function described. RESULTS: Perceptual voice quality evaluation by a professional jury of listeners is still considered to be the most reliable and complete means of evaluating pathologic voice, even though it is difficult to perform in routine and the results lack reproducibility. The objective evaluation of the vocal fundamental frequency and its variations and the spectral characteristics of voice has the advantage of being simple to perform, reproducible and quantifiable. However, automatic measurements need to be analyzed with precaution for severe dysphonia, the computer algorithms being designed for voices retaining a certain periodicity. Aerodynamic measurements are quantifiable and reproducible and provide information as to the quality of laryngeal function as a transducer of aerodynamic energy into acoustic energy. Videostroboscopy and electroglottography provide information as to the quality of the laryngeal vibrations, the source of sound production. CONCLUSIONS: All of these types of analysis are complementary, informing as to different aspects of vocal quality and laryngeal function. No one measurement alone can diagnose or characterize dysphonia.

Electrodiagnosis↗
PubMed1996

Characterization of sounds emanating from the human temporomandibular joints.

Sounds from the temporomandibular joint were recorded on audiotape from 238 individuals by placing microphones in both ears. The recordings were later digitized at a sample rate of 1.7 kHz with 10-bit resolution and stored on computer disk. At least two open-close cycles were assessed from each individual; 2707 different individual sounds were analysed in the time and frequency domains. The sounds were classified as: (a) single, short duration (clicks), (b) multiple, short-duration (creaks) and (c) long duration (crepitus). The sounds were further subclassified into either high or low amplitude by (i) the attack, which produced hard and soft categories and (ii) comparing the amplitude between sides-bilateral sounds were those with amplitudes differing by < 40 mV; the rest were unilateral. To establish the robustness of the classification 42 acoustic events were selected to be classified visually by three observers on two separate occasions. Intraobserver agreement was 82% (kappa = 0.75) while interobserver agreement was 60% (kappa = 0.71). Statistically significant differences were noted between all classifications of sound. These were most marked in the time domain. A simple, automated classification scheme was devised that was capable of categorizing the sounds with 82% agreement (kappa = 0.71) compared to a human observer.

Adolescent↗
PubMed2001

The voice of emotional memory: content-filtered speech in panic disorder, social phobia, and major depressive disorder.

We asked patients with either panic disorder, social phobia, or major depressive disorder and healthy control participants to describe their most frightening experience and to describe an emotionally neutral experience. Both fear and neutral autobiographical memories were audiotaped and processed through a low-pass filter that eliminated frequencies above 400 Hz, thereby abolishing semantic content but leaving paralinguistic aspects like rate, pitch, and loudness intact, and these convey emotional cues. Raters blind to content and diagnosis rated the content-filtered speech clips on emotional dimensions. The results revealed that content-filtered fear memories received significantly higher ratings on anxious, aroused, and dominant (but not sad or negative) scales than did content-filtered neutral memories, irrespective of the diagnostic status of the speaker. Content-filtered speech appears promising as an on-line probe of emotional processing during accessing of autobiographical memories.

Adult↗
PubMed2000

Causal cognition in a non-human primate: field playback experiments with Diana monkeys.

Crested guinea fowls (Guttera pucherani) living in West African rainforests give alarm calls to leopards (Panthera pardus) and sometimes humans (Homo sapiens), two main predators of sympatric Diana monkeys (Cercopithecus diana). When hearing these guinea fowl alarm calls, Diana monkeys respond as if a leopard were present, suggesting that by default the monkeys associate guinea fowl alarm calls with the presence of a leopard. To assess the monkeys' level of causal understanding, I primed monkeys to the presence of either a leopard or a human, before exposing them to playbacks of guinea fowl alarm calls. There were significant differences in the way leopard-primed groups and human-primed groups responded to guinea fowl alarm calls, suggesting that the monkeys' response was not directly driven by the alarm calls themselves but by the calls' underlying cause, i.e. the predator most likely to have caused the calls. Results are discussed with respect to three possible cognitive mechanisms - associative learning, specialized learning programs, and causal reasoning - that could have led to causal knowledge in Diana monkeys.

Animals↗
PubMed2001

Segmentation of the speech stream in a non-human primate: statistical learning in cotton-top tamarins.

Previous work has shown that human adults, children, and infants can rapidly compute sequential statistics from a stream of speech and then use these statistics to determine which syllable sequences form potential words. In the present paper we ask whether this ability reflects a mechanism unique to humans, or might be used by other species as well, to acquire serially organized patterns. In a series of four experimental conditions, we exposed a New World monkey, the cotton-top tamarin (Saguinus oedipus), to the same speech streams used by Saffran, Aslin, and Newport (Science 274 (1996) 1926) with human infants, and then tested their learning using similar methods to those used with infants. Like humans, tamarins showed clear evidence of discriminating between sequences of syllables that differed only in the frequency or probability with which they occurred in the input streams. These results suggest that both humans and non-human primates possess mechanisms capable of computing these particular aspects of serial order. Future work must now show where humans' (adults and infants) and non-human primates' abilities in these tasks diverge.

Adult↗
PubMed1999

Correlates of linguistic rhythm in the speech signal.

Spoken languages have been classified by linguists according to their rhythmic properties, and psycholinguists have relied on this classification to account for infants' capacity to discriminate languages. Although researchers have measured many speech signal properties, they have failed to identify reliable acoustic characteristics for language classes. This paper presents instrumental measurements based on a consonant/vowel segmentation for eight languages. The measurements suggest that intuitive rhythm types reflect specific phonological properties, which in turn are signaled by the acoustic/phonetic properties of speech. The data support the notion of rhythm classes and also allow the simulation of infant language discrimination, consistent with the hypothesis that newborns rely on a coarse segmentation of speech. A hypothesis is proposed regarding the role of rhythm perception in language acquisition.

Adult↗
PubMed1998

An algorithm for the automatic differentiation between the speech of normals and patients with Friedreich's ataxia based on the short-time fractal dimension.

In this paper, we describe an algorithm, based on acoustic pattern matching techniques, for providing an automatic, highly reliable distinction between normal and some kind of pathological speech (Friedreich's ataxia disease). For each utterance, the short-time fractal dimension parameter and, for comparison, the zero-crossing and energy ratio parameters are evaluated and used in the classification task by means of a dynamic programming procedure. Although all the parameters are able to differentiate the two groups, the fractal dimension parameter seems to provide a more reliable pattern classification than zero-crossing and energy ratio. Finally, we point out that, to the discrimination purpose, an accurate choice of the utterances to be pronounced by the subjects is to be considered.

Adult↗
PubMed2006

Synaesthesia: pitch-colour isomorphism in RGB-space?

A new experimental technique found coloured-hearing synaesthetes to possess localised isomorphism between pitch and colour. We found significantly more consistency in synaesthetes' pitch-colour matches than controls, with matches unaffected by musical experience, not facilitated by absolute pitch (AP) and responded to on the basis of pitch alone, without interference from note-name information. Synaesthetes also placed their colour responses to quartertones (notes falling between adjacent semitones) significantly closer to the RGB midpoint of their responses to the semitones lying either side. This is partial evidence for a direct, localised pitch-colour correspondence. Criteria for possible between-synaesthete similarities in patterning are also discussed, with limited evidence for localised patterning presented.

Adolescent↗
PubMed2006

Sound-colour synaesthesia: to what extent does it use cross-modal mechanisms common to us all?

This study examines a group of synaesthetes who report colour sensations in response to music and other sounds. Experiment 1 shows that synaesthetes choose more precise colours and are more internally consistent in their choice of colours given a set of sounds of varying pitch, timbre and composition (single notes or dyads) relative to a group of controls. In spite of this difference, both controls and synaesthetes appear to use the same heuristics for matching between auditory and visual domains (e.g., pitch to lightness). We take this as evidence that synaesthesia may recruit some of the mechanisms used in normal cross-modal perception. Experiment 2 establishes that synaesthetic colours are automatically elicited insofar as they give rise to cross-modal Stroop interference. Experiment 3 uses a variant of the cross-modal Posner paradigm in which detection of a lateralised target is enhanced when combined with a non-informative but synaesthetically congruent sound-colour pairing. This suggests that synaesthesia uses the same (or an analogous) mechanism of exogenous cross-modal orienting as normal perception. Overall, the results support the conclusion that this form of synaesthesia recruits some of the same mechanisms used in normal cross-modal perception rather than using direct, privileged pathways between unimodal auditory and unimodal visual areas that are absent in most other adults.

Adult↗
PubMed2003

R-citalopram attenuates anxiolytic effects of escitalopram in a rat ultrasonic vocalisation model.

Escitalopram mediates the serotonin reuptake inhibitory effect of citalopram. To investigate the potential interactive effects between escitalopram and R-citalopram, they were studied at standard and elevated serotonin levels in a model predictive of anxiolytic activity (inhibition of footshock-induced ultrasonic vocalisation in adult rats). At standard levels, citalopram partially inhibited (64%) and escitalopram abolished (97%) vocalisation. Co-treatment with L-5-hydroxytryptophan resulted in complete inhibition with citalopram and a substantially enhanced response to escitalopram, while R-citalopram increased the vocalisation significantly. Furthermore, R-citalopram attenuated the effect of escitalopram. These findings may be relevant to the enhanced clinical efficacy seen with escitalopram compared to citalopram.

5-Hydroxytryptophan↗
PubMedDate not supplied

Second formant transitions in fluent speech of persistent and recovered preschool children who stutter.

UNLABELLED: This study investigated frequency change and duration of the second formant (F2) transitions in perceptually fluent speech samples recorded close to stuttering onset in preschool age children. Comparisons were made among 10 children known to eventually persist in stuttering, 10 who eventually recovered from stuttering, and 10 normally fluent controls. All were enrolled in the longitudinal Stuttering Research Project at the University of Illinois. Subjects fluently repeated standard experimental sentences. The same 36 perceptually fluent target segments (syllables embedded in words) from each subject's repeated sentences were analyzed. The syllables were divided into three phonetic categories based on their initial consonant: bilabial, alveolar, and velar placement. The frequency change and duration of F2 transitions were analyzed for each of the target CV segments. F2 transition onset and offset frequencies and their interval (duration) were measured for each utterance. Data indicate that near stuttering onset, children whose stuttering eventually persisted demonstrated significantly smaller frequency change than that of the recovered group. It is suggested that the F2 transitions should continue to be investigated as a possible predictor of stuttering pathways. LEARNING OUTCOMES: (1) Readers will learn about studies regarding second formant transition related to stuttering. (2) Readers will learn about differences between children who persist in stuttering and those who recover from stuttering. (3) Readers will learn about research concerned with early identification of risk criteria in persistent stuttering.

Child, Preschool↗
PubMedDate not supplied

Perceptual effects of a flattened fundamental frequency at the sentence level under different listening conditions.

UNLABELLED: The purpose of this series of experiments was to examine the effect of a flattened fundamental frequency (F0) contour on the intelligibility of sentence length material in different listening environments. Eight speakers of different genders and ages produced sentences from the Speech Perception in Noise Test (SPIN). Each utterance was subjected to a resynthesis technique that allowed flattening of the fundamental frequency while maintaining the timing and spectral characteristics of the utterances. To avoid learning effects two groups of listeners were chosen to complete word transcription and interval scaling tasks of the unmodified and flattened F0 utterances under different listening conditions (competing white noise or multi-speaker babble) to obtain measures of speech intelligibility. Results were that a flattened fundamental frequency contour negatively influences speech intelligibility regardless of the nature of the competing background noise. LEARNING OUTCOMES: (1) To appreciate the role fundamental frequency variation plays in speech intelligibility. (2) To understand the importance of considering environmental noise in clinical speech intelligibility testing.

Adult↗
PubMedDate not supplied

Effects of a pressure target on laryngeal airway resistance in children.

The purpose of this study was to determine the effects of an intraoral air pressure target on estimation of laryngeal airway resistance (LAR) in normal children. Ten children produced the syllable /pi/ (a) with self-determined normal loudness, (b) with increased loudness, and (c) at a predetermined intraoral air pressure level of 6.5 to 7.5 cm of water. The target pressure level was selected because it was expected to result in estimated subglottal pressures that were lower than those associated with self-determined loudness levels. Results indicated significant differences in estimated subglottal pressure among the three conditions. As expected, estimated subglottal pressures were highest during loud speech and lowest during the pressure target task. LAR values associated with normal loudness were similar to values previously reported for children. The use of the pressure target resulted in LAR values that were reduced by 31% from normal loudness. These resistance values, however, were still greater than those reported for adult speakers at similar subglottal pressure levels. The results are explained relative to preferred loudness levels and vocal tract size differences in children and adults. It is suggested that use of a pressure target during estimation of LAR in children may provide additional data that more accurately reflect the aerodynamic integrity of the larynx. Implications for clinical assessment are discussed.

Adult↗