Scene processing precedes object processing: Evidence from EEG decoding

In the real world, objects are perceived within the context of a background scene, rather than in isolation. When an object is presented within a scene, which is processed first—the object or the scene? What roles do edge and surface information play in the neural representation of objects and scenes? To address these questions, we combined EEG and multivariate pattern analysis (MVPA) methods in a one-back task. Participants viewed images of objects embedded in scenes, presented as color photographs, grayscale images, or line drawing. Decoding resulting revealed that scenes were processed earlier than objects across all three image versions. Additionally, edge information alone was sufficient for the neural representation of objects, while surface information was primarily involved in the neural representation of scenes. These findings provide neural evidence supporting the “scene-first” hypothesis and highlight the distinct roles of edge and surface information in dynamic processing of objects and scenes.