Vocal indices of stress: a review.

OBJECTIVE: Identification of stress patterns in the voice has multiple potential applications. The objective was to review literature pertaining to the effects of various forms of stress upon the healthy voice. STUDY DESIGN: Literature review, discussion of results, and direction for further study. METHODS: This review article offers a model of stress and a review of the historical and recent research into the effects of stress on the voice. Electronic databases were searched using the key words. No studies were excluded on the basis of design; however, an attempt was made to include in the discussion studies which primarily address physiological and acoustic vocal parameters. The results of greater than 50 studies examining the effect of stressors ranging from lie and guilt to high altitude and space flight upon the voice were included in the review. RESULTS: Increase in fundamental frequency is the most commonly reported effect of stress in well-controlled trials. The trend, however, is not universal. A reduction in noise as reflected by the diminished vocal jitter is reported, but less frequently. CONCLUSIONS: Stress types, gender, and individual differences in baseline autonomic tone may explain the primarily equivocal findings of effects of stressor exposure or perceived stress on voice; and as such, the article concludes with a discussion of directions for future study.

Aerodynamic indices of velopharyngeal function in childhood apraxia of speech.

Childhood apraxia of speech (CAS) is characterized as a deficit in the motor processes of speech for the volitional control of the articulators, including the velum. One of the many characteristics attributed to children with CAS is intermittent or inconsistent hypernasality. The purpose of this study was to document differences in velopharyngeal function in children diagnosed with CAS from children with typically-developing speech. Pressure-flow techniques were used to estimate the velopharyngeal port size and measure the temporal sequencing of airflow and pressure events associated with production of a nasal + oral plosive sequence in the speech of three children with CAS and three age-matched comparison participants. The results of this pilot study revealed significant differences between the performance of the CAS group and the comparison group in three timing measures of velopharyngeal port closure and velopharyngeal orifice area during speech.

Beta-adrenergic blockade and voice: a double-blind, placebo-controlled trial.

This study investigated the effects of laboratory-induced stress and beta-adrenergic blockade on acoustic and aerodynamic voice measures. In a double-blind, placebo-controlled trial, 12 participants, six males and six females, underwent cold pressor-induced sympathetic activation followed by placebo or treatment with 40 mg propranolol. Aerodynamic and acoustic parameters of voice were collected at baseline, during cold pressor and after treatment with propranolol or placebo. Fundamental frequency, jitter, shimmer, maximum airflow declination rate, voice onset time, speaking rate, and subglottal pressure were measured at baseline, during cold pressor-induced stress, and after treatment with propranolol or placebo. Cardiovascular measures served as indicators of sympathetic nervous system (SNS) activation by cold pressor and antagonism by propranolol, and were collected during all conditions. Cold pressor appeared to adequately agonize the SNS as indicated by significant increases in resting systolic and diastolic blood pressure and heart rate. Propranolol appeared to adequately antagonize the SNS for the participants. Jitter ratio demonstrated a statistically significant increase in the participants treated with propranolol. Speaking rate demonstrated a small but significant increase in the placebo control group during cold pressor. Gender differences were observed in a few measures. Cold pressor adequately agonized and propranolol adequately antagonized the SNS. No statistically significant differences across subjects were observed in the voice parameters during cold pressor-induced stress before treatment. Jitter ratio increased significantly during propranolol treatment and cold pressor. Speaking rate demonstrated a statistically significant increase during cold pressor in the placebo control group. Gender differences were observed, but were few.

The effect of acid suppression on upper airway anatomy and obstruction in patients with sleep apnea and gastroesophageal reflux disease.

STUDY OBJECTIVES: This study was designed to assess the effect of acid suppression on upper airway structure and function in patients with obstructive sleep apnea syndrome (OSAS) and gastroesophageal reflux disease (GERD). METHODS: This is a single-site within-subjects design. Twenty five patients with documented mild OSAS and objectively documented GERD via 24-hour pH measurement were included in the study. Patients were studied before and after 8 weeks of treatment with rabeprazole, 20 mg, twice a day. Subjects underwent laryngoscopy, polysomnography, and 24-hour pH monitoring. Subjective assessments of sleep obtained included the Pittsburg Sleep Quality Index and the Epworth Sleepiness Scale. RESULTS: Posterior commissure edema was significantly reduced (p < 0.05), and the Reflux Finding Score was improved (p < 0.07). Objective and subjective sleep parameters were significantly improved, sleep-onset latency was significantly reduced (26.2 vs 11.2, p < 0.05), and sleep-related acid contact time was significantly reduced (8.0% vs 1.7% p < 0.001). There was no significant change in the apnea-hypopnea index. CONCLUSIONS: In patients with mild OSAS and documented GERD, acid suppression improves upper airway abnormalities, as well as objective and subjective measures of sleep quality. Aggressive treatment of GERD in patients with OSAS may be helpful in the overall treatment of this select patient population.