We plan a research program in the neurophysiology, psychophysics and biophysical analysis of normal and abnormal visual and oculomotor processes. Productive collaboration between basic scientists and clinical investigators will be emphasized. The program will comprise work in the following major subdivisions: 1) Human oculomotor physiology - quantitative study of the mechanisms underlying the control of mechanics of normal and abnormal eye movements. 2) Oculomotor neurophysiology - an investigation of eye movement integrating mechanisms. 3) Strabismus research - a study of vergence mechanisms and saccadic velocity in various eye movement disorders. 4) Non-surgical alignment techniques - an effort to develop techniques for drug injection into the extraocular muscle as a replacement for surgery. 5) Development of guidelines for strabismus surgical planning - a computer program to utilize quantitative information to guide strabismus surgical techniques. 6) Eye rotation measurements in strabismus - a program to assess translational and rotational movements in an accurate, quantitative fashion. 7) Perception of space and motion in binocular vision - a study of the normal and abnormal perceptual mechanisms in strabismus. 8) Sensory substitution - the design, testing and application of technical approaches leading to the development of advanced instrumentation to meet the needs of the blind in education, employment and mobility. 9) Retinal and cortical diseases - diagnosis using psychophysics and electrophysiology.