Is evidence for late selection due to automatic or attentional processing of stimulus identities?

The space of an object: Object attention alters the spatial gradient in the surround.

“…Thus, our account predicts that any effect of OBA, including the center of mass effects demonstrated in these experiments, should be subject to the broader constraints of the experimental context. Previous research has demonstrated that probability manipulations are capable of modulating spatial and object-based attentional effects (Fournier & Shorter, 2001; Shomstein & Yantis, 2002, 2004). If the far-object target were much more probable than the near-object target, the RT advantage of the near-object target should be eliminated.…”

Competition between color salience and perceptual load during visual selection can be biased by top-down set

“…Theeuwes, Kramer, and Belopolsky (2004) examined this issue by randomly mixing or blocking high-and lowload displays using a paradigm in which perceptual load was manipulated via the perceptual similarity of the target and nontargets (Lavie & Cox, 1997; note that Theeuwes et al used I C as their measure of distractor interference). Theeuwes et al found that distractor interference was modulated by intertrial contingencies that arose from the random mixture of high-and low-load displays, in that observers were more likely to attend to the irrelevant distractor in the high-load condition when the preceding trial was low in perceptual load than when it was high in perceptual load (see also Fournier & Shorter, 2001, for other evidence that distractor interference may be modulated by knowledge-of-target-probabilities under conditions of high perceptual load). This finding in turn suggested that the effects of perceptual load may be modulated by the attention-allocation set of the observer.…”