John S. Werner, a UC Davis neuroscientist and international authority on visual perception, has been selected to receive the 2015 Verriest Medal from the International Colour Vision Society for his contributions to understanding the structural and functional basis of color vision, how and why vision changes across the life span, and factors that contribute to loss of vision associated with disease. He will receive the award at the society’s biennial symposium in Sendai, Japan, in July.
Understanding, monitoring visual mechanisms
A distinguished professor at the UC Davis Eye Center and director of the Vision Science and Advanced Retinal Imaging Laboratory, Werner uses several different approaches to investigate both normal aging and age-
related diseases leading to blindness. These include psychophysical methods to show how perception of color adapts to changes in the degree of illumination throughout the day; electrophysiological methods to detect and quantify the response of cells at the back of the eye when stimulated by light; and custom instruments unique to his laboratory for ultra-high resolution. Imaging of the human retina at the cellular level, revolutionizing the field of vision science and the noninvasive diagnosis and monitoring of eye diseases.
One class of instrument uses adaptive optics to correct temporally varying, higher-order aberrations of the eye. Another class of instrument uses interferometry to detect faint reflections from cells that would otherwise make them invisible in the living eye.
Phase-variance optical coherence tomography, for example, is a noninvasive imaging technique that generates 3D volumetric images of the retina, its microvasculature and other retinal layers without the need for fluorescent dyes. This discovery, recently published in the Proceedings of the National Academy of Sciences, has the potential to evaluate therapies and understand the underlying mechanisms of diseases of the retina and optic nerve, such as age-related macular degeneration progression, the latter of which is a leading cause of vision loss among people age 50 and older in the U.S. for which there is no cure. This movie shows the region of the retina, called the optic nerve, where fibers leave the eye and send their signals to different regions of the brain.
Innovating to advance vision science
Werner has made important contributions to understanding the development and aging of color mechanisms, as well as the processes of aging in perception, particularly as they relate to plasticity and potential clinical applications. He has demonstrated the function of the different classes of color receptor and their connections to the first visual area of the brain in infants as young as four weeks of age. Reductions in the response of these receptor types changes slowly from early adulthood and continues throughout life. His work showed that when the lens of the eye is removed in cataract surgery, the light reaching the back of the eye changes dramatically, leading to color vision changes that are slowly compensated in the brain to restore normal perception.
Throughout his career, Werner has maintained an active interest in opponent color mechanisms, color in art and color illusions. Some examples have appeared in popular venues such as Scientific American and a series of lectures held at the Crocker Art Museum in Sacramento, the Duke Institute for Brain Sciences and Duke University’s Nasher Museum of Art.
Werner received his doctoral degree in psychology from Brown University and conducted postdoctoral research at the Institute for Perception TNO in Soesterberg, The Netherlands. He was a member of the psychology faculty at the University of Colorado, Boulder, before joining UC Davis in 2000, where he holds appointments in the Center for Neuroscience, College of Biological Sciences and School of Medicine. He has co-edited several books that bring together discoveries from anatomy, physiology and psychophysics to illuminate fundamental mechanisms underlying human perception. These include Visual Perception: The Neurophysiological Foundations, Color Vision: Perspectives from Different Disciplines, The Visual Neurosciences and The New Visual Neurosciences.
For his many contributions to the field of visual perception Werner has received many honors and awards. He is a fellow of the American Association for the Advancement of Science, American Psychological Association, American Psychological Society, Association for Research in Vision and Ophthalmology, the Gerontological Society of America and the Optical Society of America. He received the Pisart Vision Award from Lighthouse International and he presented the University of Colorado, Boulder, distinguished research lecture and the Optical Society of America Robert M. Boynton lecture. He has received a research prize from the Alexander von Humboldt Foundation in Bonn and was an elected scholar at Caius College, University of Cambridge.