Professor Emeritus of Optometry and Vision Science
School of Optometry
Professor of the Graduate School
Neuroanatomical pathways for the control of eye position and movement; gaze holding, image stabilization, and tracking eye movement systems; oculomotor signs of disorders of the central nervous system (palsies, nystagmus, ophthalmoplegia, cogwheel pursuits, saccadic dysmetria); the near visual-motor response and the synergistic coupling of accommodation and convergence; binocular misalignment (heterophoria and fixation disparity); and presbyopia.
Binocular vision; human development, ocular motility, strabismus, and amblyopia
The central theme of my research activities is motor-sensory properties of binocular vision. Oculomotor studies are of accommodation, vergence, and yoked versional eye movements. Studies of accommodation investigate its stimulus (contrast increment thresholds and odd-error cues such as looming) as well as adaptive responses of tonic accommodation to lenses. Studies of vergence eye movements also investigate its stimulus (features of the luminance distribution used to encode disparity and interactions between depth stimuli to vergence) and tonic vergence adaptation. The organization of mutual cross-coupling interactions between accommodation and vergence are also under investigation. Recently we have begun an investigation of adaptability of the yoking between versional eye movements (Hering’s Law) in response to aniseikonia. Sensory studies of binocular vision are of stereopsis, binocular rivalry, and depth cue interactions.
Studies of stereopsis investigate depth hyperacuities (vernier offset, gap resolution, and thickness discrimination), the spatial features in the luminance distribution used to compute disparity, and contrast effects in the disparity domain (proportion of correlation). Investigations of binocular inhibitory interactions include spatial interactions in binocular orientation rivalry and suppression of anisometropic blur.
Finally, we are investigating non-linear interactions of depth cues such as looming and dynamic disparity in suprathreshold depth perception.
Unique aspects of the lab include the SRI eye tracker-optometer apparatus, modeling of binocular motor control, and unique studies of sensory motor interaction.
Tong J, Zhang Z, Cantor C, Schor CM (2012). The effect of perceptual grouping on perisaccadic spatial distortions. Journal of Vision, 12(10):10, 1-16.
Polat U., Schor C, Tong J., Zomet A., Lev M., Yehezkel O., Seterkin A., Levi DM. (2012) Training the brain to overcome the effect of aging on the human eye. Nature, Scientific Reports 2, Article 278, doi:10.1038/srep00278 Feb 23
Vedamurthy, I., Lin M., Tong J., Yeh TN., Graham AD., Green H., Wang SL., Sabharwal A., Schor CM. (2012) Does Ethnicity Influence Short-Term Adaptation to First Reading Correction? Optometry and Vision Science, 89, 435-445
Maxwell, J., Tong, J., and Schor, C.M. (2012) Short-Term Adaptation of Accommodation, Accommodative Vergence and Disparity Vergence Facility Vision Research, 62, 93-101
Maxwell, J., Tong, J., and Schor, C.M. (2010) The first and second order dynamics of accommodate convergence and disparity convergence Vision Research, 50(17), 1728-1739
Tahir, H.J., Tong, J.L., Geissler, S., Vedamurthy, I., Schor, C.M.(2010) Effects of accommodation training on accommodation and depth of focus in an eye implanted with a crystalens intraocular lens. Journal of Refractive Surgery, 50(7), 26(10), 772-779
Zhang, Z., Cantor, C., and Schor, C.M. (2010) Perisaccadic Stereo Depth with Zero Retinal Disparity. Current Biology, 20(13) 1176-1181
Vedamurthy, I., Harrison, W.W., Liu, Y., Cox, I. and Schor, C.M. (2009) The Influence of First Near-Spectacle Reading Correction on Accommodation and Its Interaction with Convergence Investigative Ophthalmology and Vision Science, 50(9), 4215-4222
Schor, C.M. (2009) Charles F. Prentice Award Lecture 2008: Surgical correction of presbyopia with intraocular lenses designed to accommodate Optometry and Vision Science, 86(9), 1028-1041
Schor, C.M. (2009) Neuromuscular plasticity and rehabilitation of the ocular near response Optometry and Vision Science, 86(7), 788-802
Bharadwaj, S.R., Vedamurthy, I. and Schor, C.M. (2009) Short-term adaptive modification of dynamic ocular accommodation. Investigative Ophthalmology and Vision Science, 50(7), 3520-3528