Change perception refers to the sensitivity in perceiving changes, yet its modulation by objects has been less studied. To address this question, the gap-contingent technique was employed in the double-rectangle paradigm, with two rectangles briefly inserted between the pre-changed and post-changed stimuli. The changed items could either occur in the same rectangle (within condition) or across two rectangles (between condition). In Experiment 1, participants showed faster response times (RTs) when changes occurred within the same object compared to when changes occurred across different objects, indicating an object-based attention (OBA) effect. In the following experiments, factors such as the number of changes (Experiment 2), RT limit (Experiment 3), task difficulty (Experiment 4), and task relevance of the objects (Experiment 5) were considered, and the OBA effect was consistently observed across experiments. Additionally, the drift–diffusion model revealed faster information accumulation when changes occurred within the same object, providing further evidence for the object-based enhancement of change perception. In conclusion, the present study suggested that changes occurring within the same object are perceived better, highlighting the role of object-based attention in enhancing perceptual sensitivity.
