February 1999
Volume 40, Issue 2
Free
Articles  |   February 1999
Oscillopsia and tolerance to retinal image movement in congenital nystagmus.
Author Affiliations
  • R V Abadi
    Department of Optometry and Vision Sciences, University of Manchester Institute of Science and Technology, England, United Kingdom.
  • J P Whittle
    Department of Optometry and Vision Sciences, University of Manchester Institute of Science and Technology, England, United Kingdom.
  • R Worfolk
    Department of Optometry and Vision Sciences, University of Manchester Institute of Science and Technology, England, United Kingdom.
Investigative Ophthalmology & Visual Science February 1999, Vol.40, 339-345. doi:
  • Views
  • PDF
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      R V Abadi, J P Whittle, R Worfolk; Oscillopsia and tolerance to retinal image movement in congenital nystagmus.. Invest. Ophthalmol. Vis. Sci. 1999;40(2):339-345.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

PURPOSE: To determine the relationship between retinal image movement (RIM) and oscillopsia in subjects with idiopathic congenital nystagmus (CN). METHODS: Eye movements were recorded using an IRIS infrared system. The eye movement signal was fed back to move an otherwise stationary target on a screen and thereby modify the RIM experienced by each of the five CN subjects. The target was present with either no background (the absolute condition) or a textured background (the relative condition). Feedback gains were varied from -1.0 (i.e., 100% retinal image increase) to +1.0 (i.e., 100% retinal image decrease or complete stabilization), with 0 representing the zero feedback or stationary target condition. In the first experiment, RIM thresholds were determined for a range of feedback values. Using zero feedback, a second experiment measured the detection threshold for absolute and relative motions to a ramp-generated target movement for five CN and five control subjects. RESULTS: Under feedback control spatial constancy broke down for both increased and reduced RIM. The range of spatial constancy was greater for absolute (-0.56 to +0.44) compared with relative (-0.18 to +0.18) RIM. Motion detection thresholds for the CN group were 8 times less sensitive to the absolute and 17 times less sensitive to the relative motion of the target compared with the control group. CONCLUSIONS: These results suggest that in CN subjects perceptual stability is achieved primarily by extraretinal signals.

×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×