SPATIAL SELECTION VIA FEATURE-DRIVEN INHIBITION OF DISTRACTOR LOCATIONS

The allocation of spatial attention was measured with detection probes at different locations. Response times were faster for probes at the location of the target digit, which subjects reported, than at the loc ations of distracter digits, which they ignored. Probes at blank locat ions between stimuli produced fast responses, indicating that selectio n was accomplished by inhibiting distracter locations but not other ar eas. Unlike earlier studies using location cuing with simpler stimuli, these experiments showed no attentional differences across horizontal or vertical midlines. Attention varied Little with distance from the target, although blank locations far from the target were somewhat les s attended than were those near the target, and attention was only sli ghtly affected by expectations for stimulus location. This task demons trates a form of feature-driven spatial attention, in which locations with objects lacking target features are inhibited.