Visual short-term memory for natural scenes: Effects of eccentricity

摘要

It is well established that a range of basic visual acuities and sensitivities decline with retinal eccentricity due in part to a decline in spatial sampling in the retina. However, it is also known that not all peripheral deficits can be explained entirely by such low-level factors, suggesting a specialization of central vision for certain visual tasks. Here, we examine visual short-term memory for natural scenes and ask whether low-level factors can fully account for variations in performance across the visual field. We measure local recognition performance as a function of eccentricity for both coherent and scrambled natural scenes. We find that while spatial coherence substantially increases recognition rates for targets near fixation, the benefit of spatial coherence vanishes in the periphery. These results suggest that low-level factors cannot fully explain the decline in visual short-term memory for natural scenes in the periphery and that mechanisms selective for global configuration are largely confined to the central visual field.