The Role of Brain Processing in Vision
Although the eye is critical for vision, the images it transmits must be extensively processed in the brain before we can see. The importance of this processing is made clear by visual strokes which can cause complete blindness, although the eyes are completely unaffected.
Several faculty specialize in the brain processing of visual inputs, both to better understand the nature of central visual processing, and to develop methods to ameliorate visual loss caused by brain injury.
Dr. Krystel Huxlin and Dr. Mary Hayhoe study the visual processing involved in motion perception, visual search, walking, and eye-hand coordination. By studying how these abilities are altered by disorders of the visual system, they are beginning to develop methods for training patients with visual loss to overcome their deficits by employing new coping strategies. They are also developing other approaches to actually rehabilitate visual capabilities lost due to stroke.
Visual perception due to the highest levels of visual cortex
Dr. William Merigan has examined specific visual abilities (e.g., face recognition, color vision) that result from processing by high level, highly specialized areas of visual cortex. Damage to these areas caused by aging or stroke causes selective incapacity (e.g., inability to recognize faces), although patients remain able to perceive simple visual qualities.