Initiation of reflex glottic closure.

Review of the literature reveals scant information regarding the initiation of reflex glottic closure. Using the adult cat as our experimental model, we have attempted to analyze both the ipsilateral and crossed laryngeal adductor responses involved in reflex closure of the glottis. These ipsilateral and crossed reflexes are particularly well developed in the cat allowing their study with relative ease. From multifiber and single unit recurrent laryngeal nerve preparations, detailed descriptions of both peripheral and central neural organizations of these reflexes may be obtained. These data further elucidate the mechanism for initial incoordination of the glottic closure reflex, resulting from weak stimulus applied simultaneously to both superior laryngeal nerves, or from unilateral superior laryngeal denervation due to surgical trauma, metabolic neuropathy, or direct tumor involvement.