Biological Cybernetics

, Volume 49, Issue 2, pp 127–136 | Cite as

A proposed neural network for the integrator of the oculomotor system

  • Stephen C. Cannon
  • David A. Robinson
  • Shihab Shamma
Article

Abstract

Single-unit recordings, stimulation studies, and eye movement measurements all indicate that the firing patterns of many oculomotor neurons in the brain stem encode eye-velocity commands in premotor circuits while the firing patterns of extraocular motoneurons contain both eye-velocity and eye-position components. It is necessary to propose that the eye-position component is generated from the eye-velocity signal by a leaky hold element or temporal integrator. Prior models of this integrator suffer from two important problems. Since cells appear to have a steady, background signal when eye position and velocity are zero, how does the integrator avoid integrating this background rate? Most models employ some form of lumped, oositive feedback the gain of which must be kept within totally unreasonable limits for proper operation. We propose a lateral inhibitory network of homogeneous neurons as a model for the neural integrator that solves both problems. Parameter sensitivity studies and lesion simulations are presented to demonstrate robustness of the model with respect to both the choice of parameter values and the consequences of pathological changes in a portion of the neural integrator pool.

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Copyright information

© Springer-Verlag 1983

Authors and Affiliations

  • Stephen C. Cannon
    • 1
    • 2
    • 4
  • David A. Robinson
    • 1
    • 2
    • 4
  • Shihab Shamma
    • 3
    • 4
  1. 1.Department of Biomedical EngineeringThe Johns Hopkins Univ.BaltimoreUSA
  2. 2.Department of OphthalmologyThe Johns Hopkins Univ.BaltimoreUSA
  3. 3.The National Institutes of HealthBethesdaUSA
  4. 4.Room 355 Woods Res. Bldg. The Wilmer InstituteThe Johns Hopkins HospitalBaltimoreUSA

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