AN EXPERIMENTAL STUDY OF CONTRACTION PROPERTIES OF LARYNGEAL MUSCLES IN CAT

1) The contraction properties of the individual laryngeal muscles are described. The object muscles are the cricothyroid, the thyroarytenoid and the posterior cricoarytenoid. There is evidently a difference between the cricothyroid and the other two muscles. The former is slower in contraction compared with the latter two. The posterior cricoarytenoid appears to have almost similar properties to the thyroarytenoid, which is considered to be one of the fastest of all voluntary striated muscles. 2) The time relationship between the muscle action potential and the tension development is estimated. There is a comparatively constant lag between the onset of the muscle action potential and that of the observed tension. The latency is estimated at approximately 7 msec. 3) The cricothyroid muscle plays a role as a tensor for the vocal cord. © 1969, SAGE Publications. All rights reserved.