Abstract
Visual crowding is the reduction of one’s ability to identify or describe a target without fixating on it in the presence of flanking stimuli. The degree of target-flanker separation limits the amount of information that can be acquired from peripheral visual input [Bouma, 1970]. More recent research has shown that presaccadic shifts of spatial attention alone do not attenuate crowding [Morvan and Cavanagh, 2011], although similar presaccadic shifts of attention are known to improve task accuracy with uncrowded targets [Deubel and Schneider, 1996]. Here we tested whether a presaccadic foveal prime of a peripheral crowded target would improve recognition when saccades were directed to the target. In our experiment, two crowded letter arrays were presented gaze-contingently, one of which contained a target letter. On each trial, subjects chose to saccade to one of the two arrays. We found that saccades made to the array that contained the target resulted in improved target recognition when subjects were presented with a brief (50 ms) prime prior to the saccade. The prime only improved accuracy when subjects made a saccade to the array that contained the target. The effect required that the prime contain salient information about the crowded target stimulus, and it required a saccade to be executed. In addition, there was no effect of saccades on target identification without a prime or with an invalid prime. The foveal information available from the valid prime facilitated target identification in the periphery, indicating that presaccadic feature-based attention to a crowded target can be manipulated to diminish crowding.
Meeting abstract presented at VSS 2012