Abstract
Attention can be allocated to relevant objects based on a particular feature value or location. Recent work suggests a cued feature can also be used to direct attention away from irrelevant objects. Using a twelve-item circular search array (two colors), Arita et al. (2012) found a negative cue (distractor color) facilitated search relative to a neutral cue (color not present), but was not as efficient as a positive cue (target color). This suggests observers used the negative cue to bias search away from known irrelevant objects. Object color and hemifield position, however, were correlated – left hemifield contained items of one color, right hemifield contained items of another color. Observers could have used this correlation to convert negative cue feature into relevant location. It would be advantageous to identify which hemifield contained the cued irrelevant color, then shift attention to the opposite. If object color and hemifield position were not correlated, search in the negative cue condition might not be as efficient. We used the same search task as Arita et al. (2012), but made two changes: search arrays were segregated (left hemifield contained six red objects, right hemifield contained six blue objects) or mixed (each hemifield contained three red and three blue objects), and the cue indicated the relevant feature (red) or location (left arrow). When observers were presented with a negative location cue (irrelevant hemifield), response times were as fast as with a positive location cue (relevant hemifield). However, when observers were presented with a negative color cue, response times were as slow as with a neutral cue, even when the colors were segregated by hemifield. These results suggest that, when object color and location are not correlated, observers cannot easily use color information to employ a "template for rejection" and bias search away from known irrelevant objects.
Meeting abstract presented at VSS 2014