Study of Air Stream in Voice Production

INCLUSION CRITERIA: Criteria for inclusion of patients with ABSD: General Criteria: Symptoms present during speech and not apparent at rest. Symptoms less evident during whisper, singing or falsetto. Symptoms which become worse with prolonged speaking, practice or anxiety. Reflexive and emotional aspects of voice function are unaffected, such as coughing, laughter or crying. No surgical treatment for ABSD or injections with botulinum toxin in the last 9 months. Willing to undergo a botulinum toxin injection in the thyroarytenoid muscle. Diagnostic Characteristics: Prolonged vocal fold opening during voiceless consonants with excessive breathiness, as individuals experience difficulties in closing the vocal folds to produce vowels following voiceless consonants (p, t, k, s, f, h, th). Sounds such as "s", "h", or "k" when coming just before open vowels such as "ah" and "uh" as in "home", "coffee", and puppy" are usually most affected. Normal vocal fold movement control for non-speech tasks such as cough, throat clearance and Valsalva maneuver during fiberoptic nasopharyngoscopy. Criteria for inclusion for normal volunteers: Persons without pulmonary, neurological, otolaryngological, psychiatric or speech, voice and hearing problems as determined by medical history and examination by a physician. Persons without a respiratory difficulties such as asthma, bronchitis, or chronic obstructive pulmonary disease. No smokers or tobacco users. EXCLUSION CRITERIA: ABSD and Normal Volunteers The Following individuals will be excluded fro participation in the study: Any person with a history of respiratory difficulties such as asthma, bronchitis, or chronic obstructive pulmonary disease. Any person with abnormalities of the larynx such as benign laryngeal disease, laryngeal carcinoma, and laryngeal congenital anomaly. Any persons with reduction in vocal fold movement range during non-speech tasks, such as whistling, which would suggest either vocal fold paralysis or cricoarytenoid joint fixation or neoplasm. Any person with a functional voice disorder such as whispering aphonia or complete aphonia, or muscular tension dysphonia. Any person who report periods of symptom remission or are atypical of spasmodic dysphonia. Any person with oropharyngeal abnormalities such as velopharyngeal insufficiency, or neuromuscular disorders. Smokers and tobacco users. Any person who are currently under treatment for a major depression or manic-depressive illness, schizophrenia or a bipolar disorder. However, a history of a previous episode of a minor reactive depression would not exclude a person from participation.