Shimin Fu

This study examined potential visual search advantages in individuals with autism spectrum disorder (ASD) and explored the roles of distractor grouping and perceptual load by comparing their performance with that of typically developing (TD) controls. Participants were required to search for large or small targets under two levels of perceptual load, with distractors being either large or small. The results showed the following: (1) Search speed in the ASD group was slower than that of the TD group. (2) The effect of distractor grouping was stronger in the Target–Nontarget (T-N) size-inconsistent condition than in the consistent condition. Both groups showed a T-N size-consistency effect—response speeds in the T-N size-inconsistent condition were faster, indicating that distractor grouping improves search efficiency. (3) Under high load, the TD group exhibited a stronger T-N size-consistency effect than the ASD group, whereas no significant difference was observed under low load. This suggests that distractor grouping in the ASD group is less effective than in TD participants under high load. (4) Under the T-N size-inconsistent condition, participants with ASD detected small targets faster under low load, whereas TD participants detected large targets faster under high load. This indicates that distractor grouping facilitates visual search in ASD under low load. Both groups focus more on targets under high load. In conclusion, although ASD shows no search advantage, improving distractor grouping can speed up target search. Nevertheless, under high load, distractor grouping in individuals with ASD is weaker than in TD individuals, consistent with the weak central coherence theory. Additionally, ASD displays size asymmetry that is influenced by load, with distractor grouping aiding target detection in low load and reducing distractor processing under high load.

Attention is inherently drawn to distractors with salient physical features, yet it can also be proactively suppressed through top-down control, preventing attentional capture. However, this proactive suppression mechanism can fail under certain conditions. To explore the boundaries of proactive suppression, four experiments were conducted in the present study using the additional singleton paradigm, examining both top-down control and bottom-up factors. In Experiment 1, the singleton-search and feature-search modes were manipulated within subjects. The results revealed a singleton-presence cost in the singleton-search mode but no singleton-presence benefit in the feature-search mode, suggesting that proactive suppression becomes ineffective when search modes are inconsistent. Experiment 2 introduced trial-by-trial variation in targets and singleton distractors, demonstrating that proactive suppression remained effective, indicating its flexibility and rapid deployment. In Experiments 3 and 4, varying levels of singleton distractor salience were examined. The results revealed that proactive suppression was effective for highly salient distractors but failed for low-salience or dynamic distractors. This suggests that proactive suppression requires a certain level of salience and does not extend to dynamic distractors. In conclusion, this study validated the robustness of the proactive suppression mechanism while identifying the conditions under which it fails, shedding light on its operational boundaries. (PsycInfo Database Record (c) 2025 APA, all rights reserved).

The object‐based attention (OBA) effect has been consistently observed across various objects using the double‐rectangle paradigm, but its relevance to faces has sparked controversy. To address this issue, we used the event‐related potentials (ERP) technique to examine the temporal dynamics of object processing and its impact on the OBA effect. Behavioral data revealed the presence of the OBA effect for non‐face mosaic objects but not for faces. After correcting for attentional horizontal‐vertical symmetry, we identified two ERP components associated with the OBA mechanisms: corrected N1 and Late Positive Deflection (LPD). The corrected N1 exhibited a larger amplitude in within‐object compared to between‐object conditions, regardless of whether faces or non‐face objects were presented. In contrast, the corrected LPD showed a larger amplitude in between‐object relative to within‐object conditions, exclusively for non‐face objects. These findings suggest that the corrected N1 and LPD reflect different stages of the OBA mechanism. The early object‐based N1 component may reflect the processing of coarse perceptual entities, without detailed object information. In contrast, the later object‐based LPD component suggests a more integrated processing of objects with detailed information, where two faces are perceived as a unified whole due to their inherent social connections. This distinction between early and late mechanisms of OBA provides new insights into how attention selected two faces as either integrated or separate operational units.

Change perception refers to the sensitivity in perceiving changes, yet its modulation by objects has been less studied. To address this question, the gap-c