Abstract
In peripheral vision, it is harder to identify a target letter when it is flanked by other nearby letters. This crowding effect occurs when the flankers fall within a well-defined interference zone extending around the target to about 1/3 to 1/2 of the target’s eccentricity (the critical spacing). Here we extended a study of Geiger and Lettvin (1986) and found that crowding can be reduced by a single item presented far outside the critical spacing, either at the fovea or in the opposite visual field, when the remote item matches the crowded target. Observers were presented with an array of three horizontally arranged items, letters and numbers, with the target at the center. Stimuli were presented randomly to the left or right of fixation. Additionally, a single number or letter was presented either at fixation or at the mirror location opposite to the crowding stimulus. Observers indicated whether the target was a number or a letter. To ensure the allocation of attention to both positions, observers also indicated whether the remote item was the same as the crowded target, though the single item was not a reliable cue to the crowded target identity. Nonetheless, performance in the crowding task was improved when the single item was the same as the target compared to when they were different, indicating that target repetitions far from the target can reduce crowding. We suggest that this result is due to long-range grouping processes that precede crowding.
Meeting abstract presented at VSS 2012