Abstract
Recent findings suggest that horizontal spatial information is more informative than vertical information in conveying the identify of face images. In this study, we examined (1) the orientation bandwidth requirement for identifying face images that contain primarily horizontal or vertical spatial information; and (2) whether the orientation bandwidth requirement is different in normal foveal and peripheral vision. Six observers identified familiar face images that have been filtered using a bandpass orientation filter centering at 0° (horizontal) or 90° (vertical), with bandwidths ranging between 10° and 60°. Face images were presented at the fovea for a duration of 80 ms, or at 10° in the right visual field for 200 ms, so that the performance for the unfiltered conditions were matched. In general, the accuracy for identifying faces increased with orientation bandwidth up to the threshold bandwidth (the bandwidth corresponding to 64% accuracy). The threshold bandwidth was smaller for horizontal (fovea: 34.9°, 10°: 37.8°) than for vertical orientation (fovea: 44.8°, 10°: 46.6°), a difference that can be attributed to the fact that horizontal information is more informative about the identify of face images. Our results indicate that the orientation bandwidth requirement is largely similar between the normal foveal and peripheral vision.