Behavior of the intrinsic laryngeal muscles : Thyroarytenoid(TA), cricothyroid(CT), lateral cricoarytenoid(LCA), interarytenoid(IA) and posterior cricoarytenoid(PCA) : were evaluated under the in vivo canine laryngeal model in three individual papers. This is the review of the relating three articles. In vivo preparation of the laryngeal model was summarized. Video-laryngoscopic findings of the individual intrinsic laryngeal muscles were documented by electrical stimulation of the individual muscular branches of the laryngeal nerve. Effects on fundamental frequency, subglottic pressure, intensity and open quotient by the stimulation of the individual intrinsic laryngeal muscles were tested.