Laryngeal neurophysiology and its clinical uses

A fact well known to all otolaryngologists, but which occasionally bears repeating, is that the larynx is not just an organ of communication. The larynx sits at the crossroads of the pathways of air and food intake, and serves the vital function of keeping ingested food and water from entering the lungs. Another obvious consideration, however, is that if the larynx were not there and if the breathing and alimentary passages were totally separate (as after surgical laryngectomy), then there would be no need for the larynx other than to speak. Thus, in terms of survival of the organism, laryngectomy can be considered a viable treatment option any time laryngeal dysfunction compromises health. The problem with this line of reasoning, of course, is that speech, in humanistic terms, is a very compelling need. Someone who communicates in any mode other than that of normal speech is at a distinct disadvantage in almost any culture. Therefore, at its essence, the subspecialty of laryngology has as its central mission the preservation or restoration of normal voice and speech by the natural mechanism. In accomplishing this, it is necessary to understand how the larynx functions as an integral component of the systems for speech, breathing, and swallowing. The intent of this article is to outline essential features of laryngeal function, to describe how function is impaired by diseases, and to offer examples of the clinical significance of this information.