Object-based attention shifts are driven by target location, not object placement

Abstract

ABSTRACTObject-based attention (OBA) enhances processing within an attended object. We previously showed that OBA shifts crossing the visual field meridians were faster horizontally than vertically: a Shift Direction Anisotropy (SDA). Here we aimed to determine whether the SDA depends upon meridian crossings of object boundaries, target locations, or both. Participants viewed an “L”-shaped object and responded to a target at either cued or non-cued locations offset horizontally or vertically. Meridian crossings or non-crossings of object boundaries and target locations were manipulated across five experiments (Experiments 1–3B). In Experiment 4, the object was removed to confirm that object-based (not space-based) attentional resources drive observation of the SDA. In sum, the SDA emerged only when target locations necessitated shifts that crossed the meridians, regardless of object placement, demonstrating that the SDA is driven by target location relative to the meridians and that OBA processes prioritize specific target locations within an object.