Abstract
In general, studies of peripheral vision report that spatial acuity and form perception decline rapidly outside the fovea. The course-grained information the peripheral retina provides is inadequate for form recognition. Instead, the peripheral retina provides only cues to elements in the visual field to which we might orient. With few exceptions (e.g., Thorpe, Gegenfurtner, Fabre-Thorpe, & Bulthoff, 2001), these studies employed simple or artificial stimuli such as letters and gratings. In the current study, we examined sensitivity to socially-salient stimuli in the nasal and temporal periphery. Two human movements—walking and lunging—were depicted in high-contrast point-light displays. Each movement was performed in 5 different orientations relative to the picture plane. Foils were created from each target in each orientation by randomly relocating the point-light elements comprising the target figure. On each trial, a target or foil figure was presented in one of 14 locations throughout the horizontal visual field, from 50 deg in the nasal to 75 deg in the temporal visual field. Observers were asked to discriminate the target and foil displays viewed monocularly, with their heads held stable in a chin rest. Observers were presented either the walking or the lunging targets and the corresponding foils. We recorded discrimination accuracy and reaction time. Initial analyses suggest that observers are able to discriminate alternative forms in structure-from-motion displays at the most extreme eccentricities we tested. These results suggest that the visual periphery's ability to extract motion-carried information is not limited to optic flow information.