Distractor suppression driven by statistical regularities of target could occur only for larger search arrays.

A number of studies have suggested that biasing the probability by which distractors appear at locations in visual space may lead to attentional suppression of high-probability distractor locations. It effectively reduces capture by a distractor but also impairs target selection at this location. Recently, there is still debate on whether the distractor processing could be affected by the statistical regularities of the target location. In the current study, through four experiments, we manipulated search array size (the number of the elements on the display - four, six, ten, 12). In each experiment, we manipulated spatial regularities of the target including one low-probability target location and other high-probability target locations. We found that statistical regularities of the target location could affect the distractor processing, but this occurred only for larger search array sizes (e.g., ten and 12 elements). Our new finding provided the evidence for whether statistical regularities regarding the target could affect distractor processing. We concluded that search array size was a potential and critical factor for determining whether distractor suppression could be driven by statistical regularities of target location.