How robust is categorial distractor suppression? Assessing the impact of additional categories and increased set size.

Distractor suppression is the process of utilizing top-down information about distractors to improve search performance. Most studies have utilized simple stimuli and concluded that basic visual features are suppressed. However, recent studies have shown that categorical information can be suppressed, albeit with limited categories and display set sizes. In three experiments, we examined whether suppression for categorical distractors remained robust in more realistic search conditions by increasing the number of categories and display set sizes. Across our experiments, we modified previous experiments' paradigms where participants searched for specific t orientations that were embedded in categorical objects. In Experiment 1, we increased the number of categories. In Experiment 2, we only increased the display set size. In Experiment 3, we increased both the number of categories and the display set size. Response times were faster on trials where the cued distractor category appeared, indicating distractor suppression effects in Experiments 1 and 2 but not Experiment 3. Combined, the results suggest that categorical distractor suppression effects likely occur in more realistic contexts, but other more beneficial search strategies may also be employed with increased task complexity.