In humans and other foveate animals eye movement is essential both for clear vision and for visual information processing and cognition. The overarching goal of our research is to elucidate the neural mechanisms of eye movement control for understanding etiology of oculomotor disorders (e.g., nystagmus, strabismus, etc.) in neurological diseases and developing discriminative diagnoses and effective treatments. In this R21 proposal, we are going to simultaneously measure eye position, muscle tension (MT) and motoneuron activity of the medial and lateral recti during combined eye- head gaze shifts. The proposal meets the objectives of the R21 program in two ways: [1] This will be the first time that MT of an agonist/antagonist pair will be measured during combined eye-head gaze shifts and related to eye movement and motoneuron activity; [2] We are going to test the hypothesis that innervation of the medial and lateral recti can become non-reciprocal in the presence of interactions between saccadic gaze shifting response and gaze stabilizing response. If correct, this hypothesis would cause a paradigm shift away from the gaze control models pioneered four decades ago by DA Robinson (1968, 1975, 1978), which are the basis of most current oculomotor basic science and clinical intervention. This application will provide important knowledge not only for understanding the fundamental vestibular and oculomotor neurophysiology, but also for improving the diagnosis and treatment of vestibular and oculomotor disorders in humans.

Public Health Relevance

Gaze stabilization during head rotations is essential for clear vision. While the neural mechanisms for gaze stabilization during passive head rotations are well-established, little is known about the neural basis of gaze stabilization during active head rotations. This application will provide important knowledge for understanding the fundamental vestibular and oculomotor neurophysiology and improving the diagnosis and treatment of vestibular and oculomotor disorders in humans.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Exploratory/Developmental Grants (R21)
Project #
1R21EY025550-01
Application #
8913502
Study Section
Special Emphasis Panel (ZRG1-IFCN-T (02))
Program Officer
Araj, Houmam H
Project Start
2015-04-01
Project End
2017-03-31
Budget Start
2015-04-01
Budget End
2016-03-31
Support Year
1
Fiscal Year
2015
Total Cost
$190,625
Indirect Cost
$65,625
Name
University of Mississippi Medical Center
Department
Otolaryngology
Type
Schools of Medicine
DUNS #
928824473
City
Jackson
State
MS
Country
United States
Zip Code
39216