The role of cognitive cueing in eliciting vocal variability

Variation in duration and frequency during three readings of each of eight sentences by 9 normal and 4 voice-disordered subjects are compared. Instructions to the subjects varied with respect to the amount and type of cognitive cueing presented in the trials, and the sentences were read in random order. Variability in fundamental frequency (F₀) was greater when pitch variation was specifically cued. Also, the portion of the sentence that was cued had greater variability in F₀ than other parts of the sentence. Variation in fundamental frequency was significantly greater in the cued versus uncued sentence trials for the voice-disordered subjects but not for the normal subjects. However, all subjects exhibited significantly greater duration for cued versus uncued readings of the same sentences. Implications for theory and practice are discussed.     

Functional Characteristics of a New Electrolarynx “Evada” Having a Force Sensing Resistor Sensor

Electrolarynxes have been used as one of the rehabilitation methods for laryngectomees. Earlier electrolarynxes could not alter frequency and intensity simultaneously during conversation. Recently, we developed an electrolarynx named “Evada” (prototype so far) using a force sensing resistor (FSR) sensor that can control both frequency and intensity simultaneously during conversation. Employing three types of electrolarynxes (Evada, Servox-inton, Nu-vois), this study was undertaken to examine the functional characteristics of Evada for the normal control group and for laryngectomess. Five laryngectomees and five normal adults were asked to express three sentences (declarative sentence, “You stay here.”, interrogative sentence, “You stay here?”, and imperative sentence, “You! Stay here.”) using three types of electrolarynxes. Frequency and intensity changes between the first and last vowels in the three sentences were calculated and analyzed statistically by paired t test. The frequency changes in the interrogative and imperative sentences were more prominent in Evada than in Servox-inton and Nu-vois. The intensity changes in the interrogative and imperative sentences were also more prominent in Evada than in Servox-inton and Nu-vois. Evada controls frequency and/or intensity by having the subject press the control button(s). Therefore, Evada appears to be better at producing intonation and contrastive stress than Nu-vois and Servox-inton.     

Acoustic Analyses of Developmental Changes and Emotional Expression in the Preverbal Vocalizations of Infants

The nonverbal vocal utterances of seven normally hearing infants were studied within their first year of life with respect to age- and emotion-related changes. Supported by a multiparametric acoustic analysis it was possible to distinguish one inspiratory and eleven expiratory call types. Most of the call types appeared within the first two months; some emerged in the majority of infants not until the 5th (“laugh”) or 7th month (“babble”). Age-related changes in acoustic structure were found in only 4 call types (“discomfort cry,” “short discomfort cry,” “wail,” “moan”). The acoustic changes were characterized mainly by an increase in harmonic-to-noise ratio and homogeneity of the call, a decrease in frequency range and a downward shift of acoustic energy from higher to lower frequencies. Emotion-related differences were found in the acoustic structure of single call types as well as in the frequency of occurrence of different call types. A change from positive to negative emotional state was accompanied by an increase in call duration, frequency range, and peak frequency (frequency with the highest amplitude within the power spectrum). Negative emotions, in addition, were characterized by a significantly higher rate of “crying,” “hic” and “ingressive vocalizations” than positive emotions, while positive emotions showed a significantly higher rate of “babble,” “laugh,” and “raspberry.”     

Effects of HearFones on speaking and singing voice quality

HearFones (HF) have been designed to enhance auditory feedback during phonation. This study investigated the effects of HF (1) on sound perceivable by the subject, (2) on voice quality in reading and singing, and (3) on voice production in speech and singing at the same pitch and sound level.

Test 1: Text reading was recorded with two identical microphones in the ears of a subject. One ear was covered with HF, and the other was free. Four subjects attended this test. Tests 2 and 3: A reading sample was recorded from 13 subjects and a song from 12 subjects without and with HF on. Test 4: Six females repeated [pa:p:a] in speaking and singing modes without and with HF on same pitch and sound level.

Long-term average spectra were made (Tests 1–3), and formant frequencies, fundamental frequency, and sound level were measured (Tests 2 and 3). Subglottic pressure was estimated from oral pressure in [p], and simultaneously electroglottography (EGG) was registered during voicing on [a:] (Test 4). Voice quality in speech and singing was evaluated by three professional voice trainers (Tests 2–4).

HF seemed to enhance sound perceivable at the whole range studied (0–8 kHz), with the greatest enhancement (up to ca 25 dB) being at 1–3 kHz and at 4–7 kHz. The subjects tended to decrease loudness with HF (when sound level was not being monitored). In more than half of the cases, voice quality was evaluated “less strained” and “better controlled” with HF. When pitch and loudness were constant, no clear differences were heard but closed quotient of the EGG signal was higher and the signal more skewed, suggesting a better glottal closure and/or diminished activity of the thyroarytenoid muscle.     

The contribution of aryepiglottic constriction to “ringing” voice quality—A videolaryngoscopic study with acoustic analysis

Fiberscopic video laryngoscopy was performed on five professional singers to determine the presence or absence of aryepiglottic narrowing as a function of voice quality. Each sang “Happy Birthday” and parts of the “Star Spangled Banner” in six different voice qualities: speech, falsetto, sob (a low larynx with a vocal tract expanded by relaxing the middle constrictors), twang, belting, and opera. Several features were found to be common among the subjects and related to specific qualities. Aryepiglottic constriction was present in all singers in twang, belting, and opera qualities. Spectrographic analysis related the constriction to the presence of the “singer's formant.” The presence of this type of constrictive behavior will require further research to ascertain the possible benefits to those for whom a louder voice is essential and to understand the relationship of this constrictive maneuver to the natural closure functions of the larynx.     

Learning voice analysis using an interactive multi-media package: Development and preliminary evaluation

An important outcome of education for speech-language pathologypractice is the ability to analyze voices perceptually, a complex task that is often difficult for novices. This article describes an interactive multi-media package, “A Sound Judgement,” that is designed to help students develop skills in perceptual voice analysis and to link their perceptions to laryngeal physiology. The package presents a range of clients with vocal impairments at increasing levels of complexity. Each case has a videoed interview, endoscopic views and animations of the larynx, and case history information. Students make perceptual ratings of clients' voices on a format designed specifically for this package and feedback is provided using ratings made by expert speech-language pathologists. High levels of consensus for the perceptual judgments were achieved among the expert raters. Preliminary evaluations by students have demonstrated that “A Sound Judgement” is likely to be a valuable educational tool.     

The perception of two vocal qualities in a synthesized vocal utterance: ring and pressed voice

Two vocal qualities, ringquality and pressed quality, were analyzed perceptually. Listeners were asked to rate (on a scale from 0 to 10) the “amount of ring” in one listening and the “amount of pressedness” in another listening. The stimulus was the synthesized utterance /ya-ya-ya-ya-ya/. In the continuum representation of ring, the skewing quotient and the cross section of the epilaryngeal tube area were systematically varied, independently and by a covariation rule. In the continuum representation of pressed, the flow amplitude and open quotient were similarly varied. Results indicated that the crossover point between ring and no ring occurred with an epilaryngeal area of around 1.0 cm², and the crossover point between pressed and not pressed quality occurred at an open quotient of about 0.4. Fundamental frequency also had an effect on the perceptions, with a higher fundamental frequency receiving higher ratings of ring and pressed for otherwise the same parameters. Listeners demonstrated highly variable perceptions in both continua with poor intersubject, intrasubject, and intergroup reliability.     

What is “Twang”?

A single female professional vocal artist and pedagogue sang examples of “twang” and neutral voice quality, which a panel of experts classified, in almost complete agreement with the singer's intentions. Subglottal pressure was measured as the oral pressure during the occlusion during the syllable /pae/. This pressure tended to be higher in “twang,” whereas the sound pressure level (SPL) was invariably higher. Voice source properties and formant frequencies were analyzed by inverse filtering. In “twang,” as compared with neutral, the closed quotient was greater, the pulse amplitude and the fundamental were weaker, and the normalized amplitude tended to be lower, whereas formants 1 and 2 were higher and 3 and 5 were lower. The formant differences, which appeared to be the main cause of the SPL differences, were more important than the source differences for the perception of “twanginess.” As resonatory effects occur independently of the voice source, the formant frequencies in “twang” may reflect a vocal strategy that is advantageous from the point of view of vocal hygiene.     

The ChatterVox™ Portable Voice Amplifier: A Means to Vibration Dose Reduction?

By speaking loudly for extended periods, teachers are vulnerable to laryngeal and voice changes associated with vocal fold “vibration overdose.” Voice clinicians frequently recommend voice amplification ostensibly designed to reduce vibration dose and improve voice. However, there are few data regarding the degree of vocal loudness attenuation achieved by specific amplification devices. The purpose of this investigation was to examine the effectiveness of the ChatterVox™ Portable Voice Amplification System (Siemens Hearing Instruments) for reducing the sound pressure level (SPL) of a speaker's voice during a simulated classroom lecture. Ten participants were instructed to continuously read one of two phonetically balanced passages while amplified and unamplified. Voice intensity measurements were obtained at three inches from the mouth (i.e., mouth level) and at the back of a classroom in both amplified and unamplified conditions. When amplified with the ChatterVox™, speakers experienced an average decrease in vocal intensity at mouth-level of 6.03 dB SPL (p < 0.002). Furthermore, an average increase of 2.55 dB SPL (p < 0.038) at the back of the classroom was observed. Collectively, these results indicate that the ChatterVox™ amplification device reduced the speaker's vocal intensity level at the microphone, while it augmented the voice heard at the back of the classroom. By inference, this degree of vocal attenuation at mouth level should contribute to a desirable reduction in vibration dose, thus lowering the risk of vibration overdose.     

The accent method of voice therapy: Effect of accentuations on FO, SPL, and airflow

The effect of the increased flow rate (ΔU) in response to the Accent Method exercises on fundamental frequency (FO) and sound pressure level (SPL) was studied in three subjects (professionally trained, trained, and untrained in this method). In all the subjects, the rhythmic accentuated exercises produced a variable degree of increase in FO (ΔFO) and SPL (ΔSPL). The professionally trained subject showed greater ΔFO and ΔSPL in response to the ΔU in the fastest tempo, which requires higher skills. Both trained subjects showed a greater correlation between ΔU and both ΔSPL and ΔFO, as well as between ΔFO and ΔSPL, as compared to the untrained subject. The effects of the accentuated exercises on FO and SPL in response to the increased airflow rate (ΔU) thus appear to demonstrate the treating effectiveness of the Accent Method.     

The effect of task on determination of habitual pitch

The purpose of this study was to investigate if there was an effect of task on determination of habitual pitch, or speaking fundamental frequency (SFF). Seven tasks commonly used to elicit habitual pitch in clinical voice evaluations were compared. Three groups of normal subjects (N = 36) were examined (adult males, adult females, and male and female prepubescent children). For the adult male (n = 12) and pediatric (n = 12) subjects, no significant effect of task was found. For the adult female (n = 12) subjects, a statistically significant (P < .001) effect of task was found. All tasks were found to have high (>0.90) test-retest reliability for all subjects. Implications of the use of one task for determination of habitual pitch are discussed, as is the possibility of a task effect on determination of other voice parameters.     

Airway Considerations for Professional Singers—A Survey of Expert Opinion

The objective of this study was to survey physician experts in voice disorders/treatment to establish consensus guidelines for translaryngeal intubation (TLI) and tracheotomy when treating professional singers or other voice professionals. A written survey was sent to all physician members of the Voice Foundation seeking opinions/recommendations about route of TLI, duration of TLI before tracheotomy, size of endotracheal and tracheotomy tubes, and special interventions during patient care as these might differ between professional singers and nonsingers. Fifty-five percent of the physicians responded, of whom 73% classified their experience in voice care as “extensive.” A strong consensus (76%) favored a smaller endotracheal tube for singers (6–7 mm I.D. for males and 6.0 mm I.D. for females) via the oral (46%) versus nasal (36%) route. Intubation/extubation by the most expert/experienced personnel was emphasized so as to minimize direct trauma to the larynx. While intubated, strong recommendations were made to suppress gastric acid production and to minimize motion of the endotracheal tube, including patient sedation. Preferences for an early tracheotomy (6 days) versus their usual time (10 days) were approximately equal (44% vs. 50%, respectively) and most respondents (69%) recommended the same size tracheotomy tube (8.0 mm I.D. for males and 6.0 mm I.D. for females) for singers and nonsingers. Post extubation/decannulation care emphasized voice rest, retraining, continued gastric acid suppression, and the possibility of direct laryngoscopy to assess post-TLI or tracheotomy injuries.     

Zigzag wall dynamics in uniaxial in-plane magnetic thin films

An unusual right/left zigzag wall propagation in the bias (transverse) and ac fields applied simultaneously is observed. A dynamic model based on the variable coercivity, effective transverse field, transformation of the walls from asymmetric Bloch into asymmetric Néel type (and vice versa) is proposed. Degeneration of two segments of one “zig” (or “zag”) which “sense” differently the transverse field is one of the crucial point of the zigzag dynamics.     

Order-disorder transition in a system of magnetic holes

Polystyrene spheres of the same size (10–100μm) dispersed in ferrofluid produce voids, which have been denoted magnetic holes. A two-dimensional system of interacting magnetic holes confined between two glass plates and subject to rotating magnetic fields in the sample plane are studied in a light microscope. For low frequencies of the field rotation, the holes form pairs, which arrange themselves in a regular triangular lattice when stabilized with a weak constant field normal to the sample plane. By increasing the frequency of the rotating field, we observe that above a critical frequency, the steady forward rotation of the pairs is interrupted by backward rotations in short time intervals. Because the intervals of backward rotation occur at different times for each individual pair, disorder is introduced in the system, and the triangular lattice of pairs “melts” and forms a liquid-like structure at high rotation frequencies of the field. This “melting” transition is observed both directly and in light scattering experiments using a laser.     

Comments on “Spectral analysis of thermally stimulated exoelectron emission from glass deposited on metal by argon plasma treatment”

A “spectral analysis” using a fit of a single glow curve only — without kinetic check — does not prove the correctness of the model of Sakurai and Momose [Phys. Lett. A 179 (1993) 55] and thus of parameters estimated on this basis. Contrary to this a “complete analysis” yields three of four parameters directly from the experiment. Two criteria are given to verify the model experimentally.     

Voice and Physical Appearance in Female-to-Male Transsexuals

The study aims to investigate if a similar interaction between physical appearance and voice could be found in female-to-male transsexuals as had been observed in male-to-female transsexuals. A panel of judges rated “maleness” of seven female-to-male transsexuals from video-recorded speech samples using three modes of presentation: auditory-only presentation, visual-only presentation, and audiovisual presentation. For the group of transsexuals as a whole, no significant differences were found between scores given in the auditory-only mode or the visual-only mode and those given in the audiovisual mode. Analysis of individual results, however, yielded significant differences in some individuals and there was some relation with hormone treatment. There was no significant correlation between the ratings of “maleness” in the auditory-only mode and fundamental frequency. Physical appearance in female-to-male transsexuals appears not to be a strong influencing factor in general, but may interact with gender recognition based on the voice in some individuals. The absence of a correlation between fundamental frequency and rating of maleness could mean that in female-to-male transsexuals, fundamental frequency is a relatively less important factor for gender expression or perhaps also that a higher voice in males is more accepted than a lower voice in females.     

Completeness of “good” Bethe ansatz solutions of a quantum-group-invariant Heisenberg model

The sl_q(2) quantum-group-invariant Heisenberg model with open boundary conditions is investigated by means of the Bethe ansatz. As is well known, quantum groups for q equal to a root of unity possess a finite number of “good” representations with non-zero q-dimension and “bad” ones with vanishing q-dimension. Correspondingly, the state space of an invariant Heisenberg chain decomposes into “good” and “bad” states. A “good” state may be described by a path of only “good” representations. It is shown that the “good” states are given by all “good” Bethe ansatz solutions with roots restricted to the first periodicity strip, i.e. only positive-parity strings (in the language of Takahashi) are allowed. Applying Bethe's string-counting technique completeness of the “good” Bethe states is proven, i.e. the same number of states is found as the number of all restricted paths on the sl_q(2) Bratteli diagram. It is the first time that a “completeness” proof for an anisotropic quantum-invariant reduced Heisenberg model is performed.     

Effects of Testosterone Replacement on a Male Professional Singer

Testosterone has been known to play an important role in the development of the postpubertal male voice for many centuries. In fact, the prevention of pubertal development of the voice by castrating young male singers was a well-known practice, especially in Italy beginning in the sixteenth century. The “castrati” were well known for their clear, high-pitched voices. Because of the resulting small larynx and vocal folds, castrati apparently produced a distinctive resonance as well as the high pitch, which cannot be matched even by the counter tenors of today. Busy voice labs occasionally see males with sex hormone deficiencies secondary to chromosomal or gonadal problems. This is a presentation of an unusual patient who was a trained tenor singer and was found to have hypogonadism on a premarital health examination. Administration of replacement testosterone resulted in significant vocal register and voice quality changes.     

Respiratory training in voice therapy

Many patients with dysphonia do not need to modify their respiratory patterns. For those that do, a simple four-point program is offered that will usually aid the patient in developing better expiration control. First, the patient is instructed that inspiratory-expiratory respiration is a continuous ongoing movement. Imagery is used to show that there is little or no discernible gap between inspiration-expiration. The patient begins working on expiratory control by prolonging phonation with no instruction given for “taking in” a breath. The patient's task is to prolong a sound with no discernible inspiratory effort before the sound is made. The patient is then asked to match a verbal target model, making no special effort to take in a breath before producing the model. Finally, instruction is given in developing skills to take renewed breaths (catch-up breaths) when saying or singing an utterance     

Methane activation over Ag-exchanged ZSM-5 zeolites: A theoretical study

Methane activation catalyzed over Ag-exchanged ZSM-5 zeolites was investigated by using the density functional theory (DFT) with a cluster model. Two different pathways were taken into account in this work: the “alkyl” and the “carbenium” pathways. The activation barriers obtained are 34.09 and 66.63 kcal/mol for the “alkyl” and the “carbenium” pathway, respectively. The calculated results show that the activation barrier of the “alkyl” pathway is smaller than that of “carbenium” pathway. Consequently, the “alkyl” pathway is the preferential reaction pathway. A new mechanism of methane conversion in the presence of ethene was proposed. In the catalytic cycle, the initial step of methane activation proceeds with the “alkyl” pathway and the Ag⁺ cation acts as an acceptor of the methyl group, then ethene reacts with the Ag⁺CH₃⁻ group to form propene. In addition, it is found that the Ag⁺ cations play an important role in the methane activation, compared with the reaction of methane activation over H-ZSM-5.