Breathy Voice as a Compensatory Strategy for Essential Vocal Tremor: A Single Case Experiment Across Participants.

Objective: Essential vocal tremor (EVT) manifests as nearly rhythmic modulations of fundamental frequency (f) and intensity and causes a shaky voice. Although research on behavioral therapy for EVT is limited, previous studies have shown that a breathy voice reduces the perception of simulated EVT and might be an effective compensatory strategy. The current study aimed to measure the acoustical and perceptual effects of a breathy voice strategy in speakers with EVT.

Speaker-induced Suppression in EEG during a Naturalistic Reading and Listening Task.

Speaking elicits a suppressed neural response when compared with listening to others' speech, a phenomenon known as speaker-induced suppression (SIS). Previous research has focused on investigating SIS at constrained levels of linguistic representation, such as the individual phoneme and word level. Here, we present scalp EEG data from a dual speech perception and production task where participants read sentences aloud then listened to playback of themselves reading those sentences.

Task-Dependent Modulation of Auditory Feedback Control of Vocal Intensity.

Auditory feedback control of fundamental frequency (f) is modulated in a task-dependent manner. When voice pitch auditory feedback perturbations are applied in sentence versus sustained-vowel production, larger and faster vocal f responses are measured in sentence production. This task-dependency reflects the scaling of auditory targets for pitch for the precision required in each speech task.

The Effects of Masked and Delayed Auditory Feedback on Fundamental Frequency Modulation in Vocal Vibrato.

Purpose: Although relatively precise control over the extent and rate of fundamental frequency (f) modulation may be needed for optimal production of vibrato, the role of auditory feedback in controlling vibrato is not well understood. Previous studies altered the gain and timing of auditory feedback in singers producing vibrato and showed inconsistent effects on the extent and rate of f modulation, which may have been related to small sample sizes or limited analyses. Therefore, the purpose of this study was to further investigate whether the gain or timing of auditory feedback impacts control of vibrato in a larger sample of speakers and with advanced statistical analyses.

Feedback and Feedforward Auditory-Motor Processes for Voice and Articulation in Parkinson's Disease.

Purpose: Unexpected and sustained manipulations of auditory feedback during speech production result in "reflexive" and "adaptive" responses, which can shed light on feedback and feedforward auditory-motor control processes, respectively. Persons with Parkinson's disease (PwPD) have shown aberrant reflexive and adaptive responses, but responses appear to differ for control of vocal and articulatory features. However, these responses have not been examined for both voice and articulation in the same speakers and with respect to auditory acuity and functional speech outcomes (speech intelligibility and naturalness).

The Effects of Remote Signal Transmission and Recording on Acoustical Measures of Simulated Essential Vocal Tremor: Considerations for Remote Treatment Research and Telepractice.

Purpose: Studies on medical and behavioral interventions for essential vocal tremor (EVT) have shown inconsistent effects on acoustical and perceptual outcome measures across studies and across participants. Remote acoustical and perceptual assessments might facilitate studies with larger samples of participants and repeated measures that could clarify treatment effects and identify optimal treatment candidates. Furthermore, remote acoustical and perceptual assessment might allow clinicians to monitor clients' treatment responses and optimize treatment approaches during telepractice.

Characterization of Source-Filter Interactions in Vocal Vibrato Using a Neck-Surface Vibration Sensor: A Pilot Study.

Purpose: Vocal vibrato is a singing technique that involves periodic modulation of fundamental frequency (f) and intensity. The physiological sources of modulation within the speech mechanism and the interactions between the laryngeal source and vocal tract filter in vibrato are not fully understood. Therefore, the purpose of this study was to determine if differences in the rate and extent of f and intensity modulation could be captured using simultaneously recorded signals from a neck-surface vibration sensor and a microphone, which represent features of the source before and after supraglottal vocal tract filtering.

Behavioral Therapy for Tremor or Dystonia Affecting Voice in Speakers with Hyperkinetic Dysarthria: A Systematic Review.

Introduction: Hyperkinetic dysarthria is characterized by atypical involuntary movements within the speech mechanism that may affect the respiratory, laryngeal, pharyngeal-oral, or velopharyngeal-nasal subsystems and may alter speech production. Although articulatory impairments are commonly considered in hyperkinetic dysarthria, speakers with hyperkinetic dysarthria may also present with changes in voice quality, pitch, and loudness. In approximately 70% of speakers with hyperkinetic dysarthria, these voice alterations are associated with tremor or dystonia.

Auditory-Motor Control of Fundamental Frequency in Vocal Vibrato.

Purpose: The purpose of this study was to investigate how classically trained singers use their auditory feedback to control fundamental frequency (f) during production of vocal vibrato. Two main questions were addressed: (1) Do singers produce reflexive fresponses to sudden perturbation of the f of their auditory feedback during production of vibrato indicative of feedback control? (2) Do singers produce adaptive fresponses to repeated perturbation of the f of their auditory feedback during production of vibrato indicative of feedback and feedforward control? In addition, one methodological question was addressed to determine if adaptive f responses were more precisely assessed with or without an auditory cue for f during the repeated f perturbation paradigm.

Method: Ten classically trained singers produced sustained vowels with vibrato while the f and harmonics of their auditory feedback were suddenly perturbed by 100 cents to assess reflexive control or repeatedly perturbed by 100 cents to assess adaptive control.

The Effect of Pitch and Loudness Auditory Feedback Perturbations on Vocal Quality During Sustained Phonation.

Objective: Dysphonia is a reduction in vocal quality that impacts communication and is often an early sign of a voice disorder. There is little information regarding the effects of auditory feedback control of loudness and pitch on voice quality. In this study, we used both loudness-shift and pitch-shift paradigms to study the relationship between auditory feedback control and vocal quality as measured by smoothed cepstral peak prominence (CPPS), which reflects the harmonicity of the voice signal.

The Relation of Articulatory and Vocal Auditory-Motor Control in Typical Speakers.

Purpose The purpose of this study was to explore the relationship between feedback and feedforward control of articulation and voice by measuring reflexive and adaptive responses to first formant ( ) and fundamental frequency ( ) perturbations. In addition, perception of and perturbation was estimated using passive (listening) and active (speaking) just noticeable difference paradigms to assess the relation of auditory acuity to reflexive and adaptive responses. Method Twenty healthy women produced single words and sustained vowels while the or of their auditory feedback was suddenly and unpredictably perturbed to assess reflexive responses or gradually and predictably perturbed to assess adaptive responses.

The Effect of Pitch Auditory Feedback Perturbations on the Production of Anticipatory Phrasal Prominence and Boundary.

Purpose In this study, we investigated how the direction and timing of a perturbation in voice pitch auditory feedback during phrasal production modulated the magnitude and latency of the pitch-shift reflex as well as the scaling of acoustic production of anticipatory intonation targets for phrasal prominence and boundary. Method Brief pitch auditory feedback perturbations (±200 cents for 200-ms duration) were applied during the production of a target phrase on the first or the second word of the phrase. To replicate previous work, we first measured the magnitude and latency of the pitch-shift reflex as a function of the direction and timing of the perturbation within the phrase.

Sensorimotor adaptation of voice fundamental frequency in Parkinson's disease.

Objective: This study examined adaptive responses to auditory perturbation of fundamental frequency (fo) in speakers with Parkinson's disease (PD) and control speakers.

Method: Sixteen speakers with PD and nineteen control speakers produced sustained vowels while they received perturbed auditory feedback (i.e.

Evidence for Auditory-Motor Impairment in Individuals With Hyperfunctional Voice Disorders.

Purpose: The vocal auditory-motor control of individuals with hyperfunctional voice disorders was examined using a sensorimotor adaptation paradigm.

Method: Nine individuals with hyperfunctional voice disorders and 9 individuals with typical voices produced sustained vowels over 160 trials in 2 separate conditions: (a) while experiencing gradual upward perturbations in the fundamental frequency (fo) of their auditory feedback (shift-up) and (b) under no auditory perturbation (control). The shift-up condition consisted of 4 ordered (fixed) phases: baseline (no perturbation), ramp (gradual increases in heard fo), hold (a consistently higher heard fo), and after-effect (no perturbation).

The effects of physiological adjustments on the perceptual and acoustical characteristics of vibrato as a model of vocal tremor.

The purpose of this study was to investigate the effects of physiological adjustments on listeners' perception of the magnitude of modulation of voice and to determine the characteristics of the acoustical modulations that explained listeners' judgments. This research was carried out using singers producing vibrato as a model of vocal tremor. Twenty healthy adults participated in a perceptual study involving pair-comparisons of the magnitude of "shakiness" with singers' samples, which differed by fundamental frequency, vocal quality, and vowel.