Speech & Language Therapy Information

Category Archives: Voice

Voice Production

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What is voice? In simple terms, the sound produced in the larynx by the vibration of the vocal folds (vocal cords) is the voice. Certain speech sounds are voiced by this vibration. When the vocal folds are apart they are said to be abducted and when they are closed they are said to be adducted. […]

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Symptoms and Causes of Functional Dysphonia

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Symptoms of functional dysphonia There are a variety of symptoms associated with functional dysphonia and these differ from person to person. However, those listed below are fairly typical. Of course, you don’t have to experience each one of these to be experiencing a functional voice difficulty. hoarseness, huskiness, roughness or breathiness voice is too deep […]

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Functional Dysphonia

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That happens to me! Indicate the extent to which the following statements apply to you. Use a scale of 1 – 5, where 1 = ‘never’ and 5 = ‘every time I use my voice’. My voice is hoarse / husky / rough / croaky My voice tires with use My voice occasionally breaks or […]

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Goal Setting Form Voice Difficulties

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Preliminary questions Is my voice difficulty a direct control issue, i.e. is it an issue involving my own behavior that I can do something about? If so, what can I do about this? Is my voice difficulty an indirect control issue, i.e. is it an issue involving other people’s behavior? If so, what can I […]

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Voice Disorders

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Voice disorders are classified as organic, psychogenic or functional. Structural, psychological or physiological impairments affect acoustic features of the voice. Affected features include: pitch, loudness, resonance, quality and flexibility. These impairments lead to aphonia or dysphonia. This article provides examples of common voice disorders.

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S/Z Ratio

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The S/Z Ratio is an indicator of voice disorder. It measures the ability to sustain the voiceless sound ‘s’ in comparison to sustaining the voiced sound ‘z’. 95% of people who have some difficulty affecting the movement of their vocal cords have an S/Z ratio of greater than 1.40. This article demonstrates how to calculate an S/Z Ratio and how to interpret the result.

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What is reflux? The escape of acid and other digestive fluids from the stomach into the esophagus (the tube connecting the stomach to the throat) and up into the larynx (voice box). What causes it? When normal, healthy individuals eat or drink, swallowing propels food and liquid from the back of the mouth down into […]

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Laryngeal Papillomas

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What are they? Papillomas are benign growths. They do not become malignant. They occur mainly on the vocal folds but they can also appear in the larynx. They can occur as a single papilloma or in clusters like warts. In the same way that warts are caused by a virus, it’s thought that a virus […]

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Objective Measurement of Voice

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Whilst instrumental measurement of voice promises to provide an objective measure of relevant parameters, there are many elements that influence comparison of results obtained on different occasions. Reactivity, human interpretation, the control of extraneous variables and the lack of normative data are all influencing factors.

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Acoustic Measures (Norms)

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Question: I am really impressed with your site, but was wondering if you had any good references to obtain normative comparison for things such as jitter, shimmer, noise to harmonic ratio, and fundamental frequency. My Reply: It is difficult to be precise about norms for acoustic measures such as jitter, shimmer, noise-to-harmonics ratio and fundamental […]

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