The interaction of target size and background pattern on perceived velocity during visual tracking

Abstract

The effect of target size and background contour on the perceived velocity of a visually tracked target was determined using a psychophysical comparison procedure. For targets viewed against a uniform field, an increase in target size produced a modest underestimation of target velocity. For small test targets, a background of contours moving in the same direction as target motion also produced an underestimation of target velocity. A background of contours moving in the direction opposite to that of target motion produced a small, but consistent, overestimation of target velocity. As target size increased, the underestimation effect seen with striped backgrounds moving in the same direction was not enhanced. The overestimation effect seen with a striped background moving in the opposite direction was nulled by an increase in target size. © 1988 Psychonomic Society, Inc.