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Coupled Perturbation Effects During 3D Target-Tracking Indicating a Shared Control Stage for Saccades and Vergence

  • J. A. M. Van Gisbergen
  • V. Chaturvedi
Chapter

Abstract

The oculomotor field has a tradition of specialised studies that concentrate either on one of the various types of version eye movements, such as saccades, or on vergence movements. In the case of the saccadic and the vergence systems, it is often assumed that these can be regarded as distinct oculomotor subsystems that generate conjugate and disconjugate binocular command signals, respectively, and that their neural control systems at the premo-tor level are largely separate. When studied in isolation, there are indeed striking differences between the temporal characteristics of these systems. These distinctions are clearly reflected in the general layout of saccade and vergence models. Models of the saccadic system stress that saccades are too fast to allow direct visual feedback, that the system is not continuous but has to be switched on and off, and contain specific proposals about the neuronal circuitry implementing this gating mechanism. By contrast, vergence models have often assumed that these slow eye movements are directly guided by visual feedback and that they are generated by a continuous system. A number of recent studies have compared the dynamic behaviour in combined saccade-vergence movements with the temporal characteristics of pure saccades and pure vergence movements. This work showed that the combined version-vergence movement is not simply a linear summation of the required components executed in isolation.

Keywords

Saccadic Response Saccadic System Vergence Movement Vergence System Vergence Response 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 1999

Authors and Affiliations

  • J. A. M. Van Gisbergen
    • 1
  • V. Chaturvedi
    • 1
  1. 1.Department of Medical Physics and BiophysicsUniversity of NijmegenThe Netherlands

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