Handling fully irrelevant vs. potentially relevant distractors as a function of perceptual load
Manini, G., Garre-Frutos, F., Botta, F., Martín-Arévalo, E., & Lupiáñez, J.
PsyArXivPreprint
Abstract
In a previous study, we investigated how task performance is affected by fully irrelevant distractors (sharing neither features nor location with the target) vs. potentially relevant distractors (sharing features and location with it), as a function of perceptual load. We observed a systematic dissociation: the effect of potentially relevant distractors increased under high-load, whereas the effect of fully irrelevant distractors remained unchanged. However, it is unclear whether this dissociation reflected a difference between distractor types or instead resulted from two methodological factors. The present study addressed this question by testing whether the double dissociation persists even when key experimental design aspects are controlled. Namely, (i) the effectiveness of the perceptual load manipulation, and (ii) the comparability between distractor effects. In Experiment 1, we replicated the perceptual load pattern and observed the double dissociation. The effect of fully irrelevant distractors decreased under high-load, whereas that of potentially relevant distractors increased. Three subsequent experiments systematically manipulated task parameters that differ between the original perceptual load task and our previous work, to assess their contribution to an effective load manipulation. Despite these variations, the double dissociation remained robust. In a final experiment, we further improved the comparability between the effects of each distractor type by using a common baseline measure, confirming that perceptual load modulates the effects of fully irrelevant vs. potentially relevant distractors in different ways. These findings suggest that distractor processing depends critically on its task relevance, while also highlighting the need to investigate the boundary conditions of perceptual load effects.