Very short-term visual memory for size and shape

Abstract

Very short-term visual memory is often studied using partial report of alphanumeric characters to measure cue-delay effects. Although such cue-delay effects have been extensively studied, few studies have considered noncharacter stimuli, and those few were mixed in their conclusions. Here, three experiments pursued the cue-delay effect for discrimination judgments of noncharacter stimuli, such as the length of a line or the shape of a rectangle. In the line-length experiment, four lines were presented, with an auditory cue indicating one of the lines, and then a single line was presented. The observers discriminated between the length of the cued line in the first display and the length of the single line in the second display. The cues were presented either before or after the four-line stimulus. A cue-delay effect was found for these stimuli. Lengthdifference thresholds nearly doubled for cues presented 500 msec after the first display, compared with cues presented 500 msec before. A further experiment revealed a similar cue-delay effect for shape discrimination of rectangles. One reason this effect may not have been reported reliably is that it is largely evident for precues, and most previous studies used primarily postcues. In summary, the cue-delay effect is general to noncharacter stimuli. © 1988 Psychonomic Society, Inc.