This article is only available in the PDF format. Download the PDF to view the article, as well as its associated figures and tables.
We have become extraordinarily sophisticated in our understanding of the oculomotor system. From both clinical and basic directions, our appreciation of the peripheral and central structures involved in moving the eyes or holding their angle of gaze has grown enormously (eg, see Berthoz and Melvill Jones1 or Howard2 for summaries of recent experimental work and Lennerstrand et al3 for clinical studies). In spite of this sophistication, however, certain fundamental questions remain. For example, what sort of information does the brain use to keep informed of eye position? The traditional explanation, attributed to Helmholtz but, in fact, going back to the early Greeks,4 says that efferent signals sent to the eye muscles are monitored and that this outflowing signal is all that is used. The many proprioceptors in eye muscles and tendons5,6 are not believed to be playing any role in supplying position information in spite of the fact that responses
Steinbach MJ. Muscles as Sense Organs. Arch Ophthalmol. 1986;104(8):1148-1149. doi:10.1001/archopht.1986.01050200054047