The brain is remarkable in its ability to perceive a stable visual world even though the patterns on the retinas change continually as the eyes are always in motion. Voluntary redirections of gaze occur several times per second from one scene location to the next. Even in the intervals between these redirections, when it seems that gaze is fixed at a single location, microscopic eye movements, known as fixational eye movements, continually jitter the stimulus with respect to the retina. Little is known about how the normal alternation of macroscopic and microscopic eye movements affects the retinal stimulus, and about the importance of this dynamic input for the visual system.
With support from the National Science Foundation, Dr. Michele Rucci will examine the influence of eye movements on the acquisition and encoding of visual information. Experiments with human observers will analyze and compare the characteristics of visual input signals to the retina during a number of everyday viewing activities. Computer models of neuronal populations in the early stages of the visual system will be used to investigate the hypothesis that a continually changing retinal stimulus contributes to the establishment of efficient visual representations. This project addresses fundamental questions in visual neuroscience. Pathological conditions which give rise to abnormal eye movements are typically accompanied by visual impairments. Understanding the impact of eye movements on early visual processing is critical to the advancement of knowledge of how the visual system functions in health and disease.
