Ocular proprioception and efference copy in registering visual direction

Vision Res. 1991;31(11):1903-13. doi: 10.1016/0042-6989(91)90185-8.


We measured the roles of eye muscle proprioception ("inflow") and efference copy ("outflow") in registering eye position. During monocular fixation, pressing on the side of an occluded eye results in a passive rotation, changing the proprioception without affecting oculomotor efference. As we have shown previously, a constant press on the side of the viewing eye induces active resistance to rotation, changing efference because oculomotor innervation compensates for the eyepress; the viewing eye's fixation remains constant. Using these two types of eyepress, both perceived target deviations and pointing biases in an unstructured visual field were measured in 8 subjects under efference copy, proprioception and control (no eyepress) conditions. Eye deviation was measured photoelectrically. Physiological gains of efference copy and proprioception was about 5/8 and 1/4 respectively. There was no statistically significant difference between perceptual judgement and open-loop pointing. The sum of gains of efference copy and proprioception, about 7/8, indicates incomplete registration of eye eccentricity in an unstructured field, and quantitatively accounts for several previously unexplained results in the literature.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adult
  • Fixation, Ocular / physiology
  • Humans
  • Oculomotor Muscles / innervation*
  • Pressure
  • Proprioception / physiology*
  • Space Perception / physiology*
  • Vision, Monocular / physiology