Human Oculomotor Functions and Their Deficits in Traumatic Brain Injury

: Diagnosis of oculomotor system deficits requires accurate knowledge of the binocular coordination dynamics, which have been studied only sparsely in humans. To provide such essential baseline data, Aim 1 will conduct the first large-scale study of a) the normal parameters of binocular coordination dynamics during saccades, vergence and accommodation, and b) the normal range of binocular coordination and vergence instabilities during reading. These parameters will be determined by fitting an advanced model of oculomotor dynamics to eye-movement data recorded with a binocular infrared eye tracker. For Aim 2, a suite of advanced functional MRI techniques will allow us to determine, for the first time in human, the oculomotor pathways in the brainstem for the major types of eye movement control, and establish the normal means and ranges of activation levels for each nucleus as a baseline for mTBI patients. For Aim 3 we will employ the methods for measuring the oculomotor dynamics of Aim 1 and fMRI protocols of Aims 2 to characterize the deficits in brainstem eye-movement control centers in mTBI patients.