Parallel, independent attentional control settings for colors and shapes.

Attentional capture can be contingent on attentional control settings (ACSs), such that peripheral cues influence processing for a subsequent target only when they share a critical feature with the target. Our previous demonstration that two ACSs from within the same feature category can be maintained simultaneously allows us to investigate the processing stage at which such ACSs are implemented. We compared the relative efficacy of ACSs from two different feature categories (shape and color) that are associated with different levels within the visual processing hierarchy. Participants were instructed to respond to one of two colors at one location and one of two shapes at another location, while ignoring the nontarget color and shape. We observed that spatial capture was modulated by whether the cues fit an ACS, with slightly greater contingent capture effects for ACSs defined by color than by shape. Thus, two ACSs from different feature sets (color and shape) can be maintained in parallel, although effectiveness of the control set varied with the type of feature.