May 2006
Volume 47, Issue 13
ARVO Annual Meeting Abstract  |   May 2006
Cortical Networks Underlying Saccadic and Smooth Pursuit Eye Movements in AMD
Author Affiliations & Notes
  • D.M. Little
    University of Illinois Chicago, Chicago, IL
    Neurology, Rehabilitation, Anatomy & Cell Biology,
  • K.R. Thulborn
    University of Illinois Chicago, Chicago, IL
    Center for MR Research,
  • J.P. Szlyk
    University of Illinois Chicago, Chicago, IL
    Ophthalmology & Visual Sciences,
    Jesse Brown Veterans Administration Medical Center, Chicago, IL
  • Footnotes
    Commercial Relationships  D.M. Little, None; K.R. Thulborn, None; J.P. Szlyk, None.
  • Footnotes
    Support  Department of Veterans Affairs, Rehabilitation Research and Development Service, Washington, DC; Research to Prevent Blindness, Inc., NIMH
Investigative Ophthalmology & Visual Science May 2006, Vol.47, 5874. doi:
  • Views
  • Share
  • Tools
    • Alerts
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      D.M. Little, K.R. Thulborn, J.P. Szlyk; Cortical Networks Underlying Saccadic and Smooth Pursuit Eye Movements in AMD . Invest. Ophthalmol. Vis. Sci. 2006;47(13):5874.

      Download citation file:

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

  • Supplements

Purpose: : To evaluate the integrity of the cortical networks, using functional Magnetic Resonance Imaging (fMRI), that underlie saccadic and smooth pursuit eye movements in patients with age–related macular degeneration (AMD).

Methods: : Five patients with AMD (range 55 – 83 years of age, M=69.8), recruited from a reading rehabilitation program, completed two eye movement tasks while fMRI data were acquired. The patients’ visual acuities ranged from 20/76 to 20/360 in their better eye. Eye movement was monitored during scanning to insure task performance. Patients first completed a visually guided saccade (VGS) task which required alternating periods of central fixation with 3° eye movements along the horizontal plane. Patients then completed a smooth pursuit (SMP) task which required patients to follow a dot along the horizontal plane (alternating with fixation). FMRI data were acquired on a 3.0–Tesla whole body scanner (GEMS, Waukesha, WI) using serial gradient echo, echo–planar imaging. Following fMRI data acquisition, a high–resolution anatomical scan was completed for all subjects.

Results: : The networks utilized in both VGS and SMP in controls implicated regions in the frontal eye fields (FEF), supplementary eye fields (SEF), portions of both inferior and superior parietal lobules (IPL, SPL), and MT/V5. FMRI data for AMD were highly variable and were marked by a decrease or absence of activity in SEF and FEF and increased activity in SPL. In comparison, the AMD patients showed networks that were similar to controls during performance of SMP.

Conclusions: : The VGS task is traditionally thought to reflect reflexive eye movements driven by the onset of a target in the visual field. We interpret the deviant patterns of activation during the VGS in AMD to reflect the patients’ difficulties in visual search and identification of targets in their visual field. These findings may have implications for the development of rehabilitation programs aimed at AMD.

Keywords: eye movements: saccades and pursuits • age-related macular degeneration • low vision 

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.