Proprioception in extraocular muscle.

Abstract

The term proprioception was introduced by Sherrington in 1906. 1 He defined it as a reflex system for the maintenance of body and coordination of movement, and the means whereby one is conscious of body position. 2,3 The purpose of this paper is to review the anatomical and neurophysiological evidence for proprioception in extraocular muscle and skeletal muscle. It will be apparent that the proprioceptors in both extraocular and skeletal muscle (muscle spindles and Golgi tendon organs) are part of the reflex system for the maintenance of eye and body position, respectively, and of coordination of movement. Concerning the conscious appreciation of eye and body position, evidence will be presented that this position sense is mediated not by muscle proprioceptors but by joint receptors. Since there is no joint involved in eye movement, the lack of position sense cannot be cited as evidence against the presence of an effective