中華心理學刊
民95 ， 48 卷， 4 期， 369-386

Ming-Chou Ho（Chung Shan Medical University）；Paul Atchley（University of Kansas）

Abstract

Object-based attention theory proposes that attention can be directed to the content (e.g., objects) of a scene regardless of spatial restrictions. The current experiments examined if the spatial extent of objectbased 
attentional representations are also modulated by task. In three experiments, the presence of costs to switch attention between objects was found to be modulated by task difficulty, preview time for the objects, and the cue-to-target SOA. In general, simpler tasks and more time (object preview or cue-to-target SOA) allow for
object switching costs at more distant locations on an object. The attentional resources available at task time appear to limit the distance along an object at which object-based effects occur. 

Keywords: object-based attention, task type, object preview time