Ocular limit cycles induced by delayed retinal feedback

Research output: Contribution to journalArticle

Authors

Colleges, School and Institutes

External organisations

  • University of Oxford

Abstract

Lisberger's and Robinson's models of smooth pursuit predict very different results from altering retinal feedback delay. We have therefore investigated the effects of increasing the retinal feedback time delay in three normal human subjects by means of an artificial feedback paradigm. When additional delays were incorporated into the retinal feedback path a threshold was reached beyond which the eye exhibited sustained self-excited oscillations or "limit cycles". The oscillation period increased linearly (as the added delay was increased) with slopes ranging from 1.41 to 1.6 with zero-delay intercepts of between 212 and 306 ms. Contrary to our experimental findings the Robinson and Lisberger models predict that the plot of oscillation period against added delay should have a slope of 3.4 and 2.7 and an intercept of 479 and 554 ms, respectively. Neither model produced comparable limit cycles, both being unstable at delays greater than 280 ms. Our results imply that the models of smooth pursuit need to incorporate predictive control.

Details

Original languageEnglish
Pages (from-to)173-180
Number of pages8
JournalExperimental Brain Research
Volume96
Issue number1
Publication statusPublished - 1 Sep 1983

Keywords

  • Eye movements, Human, Smooth pursuit eye movements, Smooth pursuit models, Time delays

ASJC Scopus subject areas