Abstract
Visual scenes contain far too much information to be apprehended in a single glance. Limitations come from several factors, including the decline in visual resolution with distance from the fovea, the interference produced by crowding, and the inability to identify or encode multiple visual objects or features within the same brief glance. These limitations mean that effective vision depends on both saccadic eye movements and perceptual attention to select the objects, features or regions with the greatest momentary need for limited processing resources. Some approaches to saccades and attention have emphasized the strong links between the two processes in space and time, while others have emphasized their independence. This talk will present recent results from experiments that measure perceptual performance during saccadic sequences while varying memory load, perceptual load, target contrast, external noise and the cues available to guide saccades. The results show strong links between spatial attention and saccades that affect the quality of the perceptual representations, the accuracy of saccades and the contents of visual short-term memory. By contrast, feature-based attention operates largely independently of saccadic planning. The net result is that spatial attention can ensure accurate saccades and facilitate seamless transitions between glances, while attention based on features can contribute to longer-range selection of useful places to look.
Meeting abstract presented at OSA Fall Vision 2012