Second-order suppression is not proactive: Evidence from the capture-probe paradigm

Natural environments are filled with salient yet task-irrelevant information that constantly competes for attentional resources. Effectively suppressing such distracting information is critical for the attentional control system to minimize interference with ongoing cognitive processes and maintain goal-directed behavior. Using the capture-probe paradigm, this study investigated whether the visual system can suppress distractors defined by local feature discontinuities (second-order suppression) and whether such suppression operates proactively. Experiment 1 found that when the singleton distractor had a fixed color (first-order suppression), probe recall accuracy was significantly impaired at the singleton location at both 0-ms and 200-ms array-to-probe stimulus onset asynchronies (SOAs), indicating proactive suppression. However, when the singleton distractor varied in color across trials-using either three (Experiment 2) or 12 (Experiment 3) possible colors-reliable probe suppression effects emerged only at 200-ms SOA, with no effect at 0-ms SOA. To rule out the confound of target feature enhancement, Experiment 4 employed a multiframe letter probe paradigm in which both targets and distractors varied in color across frames, and the target color in one frame could serve as the distractor color in another. Consistent with Experiments 2 and 3, probe suppression effects were observed only when probes appeared in the final frame but not the first. Together, these findings demonstrate that second-order suppression is possible but does not operate proactively; instead, it requires additional time to develop. Furthermore, this suppression operates independently of target feature enhancement. The results underscore the flexibility and context sensitivity of attentional suppression mechanisms in dynamic environments. (PsycInfo Database Record (c) 2026 APA, all rights reserved).