Rapid shifts of gaze can be accomplished either by movement of the eyes alone (eye saccades) or combined movements of eyes and head (eye-head saccades). The customary oculomotor range (COMR) is that region about """"""""central"""""""" orbital position within which a subject tends to make gaze changes by eye saccades. Prior studies suggest that COMR may be approximately plus or minus 15 degrees but it has never been studied systematically. COMR is important because: 1) The reason for its existence is unclear; it may reflect limitations in the brain's ability to compensate for the oculomotor plant, and therefore mapping COMR would also map these limitations; 2) COMR reflects the brain's choice between two different methods of accomplishing a given task (i.e., to use an eye- only or an eye-head saccade). This sort of binary selection process is accessible to electrophysiologic techniques but behavioral studies of COMR are a necessary prerequisite. The proposed investigations would determine methods of measuring COMR, describe the kinematics of eye movements made within and beyond COMR, determine whether COMR is plastic, and examine the effects of diseases of brain, orbit, and neck on COMR. These studies will also clarify the effects of such disease processes on visual function. Furthermore, by quantifying eye movements about eccentric orbital positions, these studies will establish the validity and limitations of some common clinical tests of eye movements.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Clinical Investigator Award (CIA) (K08)
Project #
5K08EY000356-02
Application #
2444239
Study Section
Special Emphasis Panel (ZEY1-VSN (03))
Project Start
1996-07-01
Project End
2000-06-30
Budget Start
1997-07-01
Budget End
1998-06-30
Support Year
2
Fiscal Year
1997
Total Cost
Indirect Cost
Name
Case Western Reserve University
Department
Neurology
Type
Schools of Medicine
DUNS #
077758407
City
Cleveland
State
OH
Country
United States
Zip Code
44106
Stahl, John S; Plant, Gordon T; Leigh, R John (2002) Medical treatment of nystagmus and its visual consequences. J R Soc Med 95:235-7
Stahl, J S; Leigh, R J (2001) Nystagmus. Curr Neurol Neurosci Rep 1:471-7
Stahl, J S; Averbuch-Heller, L; Leigh, R J (2000) Acquired nystagmus. Arch Ophthalmol 118:544-9