VIDEOENDOSCOPIC ANALYSIS OF LARYNGEAL FUNCTION DURING LAUGHTER

Although commonly encountered in all human cultures, laughter remains poorly understood. In order to examine laryngeal function during laugh ter, telescopic and fiberscopic videolaryngoscopy was performed on fiv e subjects, who laughed in the different vowels, at various frequencie s, and in several voice qualities. During laughter, the vocal folds we re found consistently to undergo rhythmic abduction and adduction. At the end of these specific phonation tasks, all subjects were able to g ain voluntary control of paramedian vocal fold positioning. This study better defined laryngeal function during laughter. These results have important clinical implications. Voluntary vocal fold positioning has important applications in speech therapy for dysphonias, such as voca l fold nodules, in which the primary cause is vocal fold hyperadductio n. Patients suffering from these hyperadductive dysphonias may be able to utilize laughter to correct them.