Influences of Object Properties to Attentional Guidance

Recent studies suggest that target-to-object relationship (whether the target appears to be a part of the object or is perceived as placed on top of an object) is the primary factor that determines whether attentional guidance is influenced by object representations (Chen & Cave, 2006; Richard, Lee, & Vecera, 2008; Hollingworth, Maxcey-Richard, and Vecera, 2012). Others, however, suggest that object-based selection is largely driven by spatial uncertainty of target location (Shomstein & Yantis, 2002; Drummond & Shomstein, 2010). Here, we re-evaluate the contribution of spatial uncertainty to object-based attentional guidance as well as examine the interaction between spatial uncertainty and target-to-object relationship. In a series of five experiments, object-based effects were measured as a function of whether the target location was known in advance (certainty manipulation) and whether the targets were perceived to be as concavities of the object (bites), floating on top of the object (floaties), or part of an object (parts). We observed object-based effects only when target location was uncertain, independent of whether the targets were interpreted as being part of the object (bites), or simply placed on top of the object (floaties). There was an exception, however, with parts failing to elicit object-based effects. These results re-instate the importance of location uncertainty in object-based attentional guidance, and suggest that object representations, placed within the boundaries of an attended object, benefit perceptually regardless of whether they are perceived to be an integral part-of or on-top-of the object. Meeting abstract presented at VSS 2013