Objects and attributes in divided attention: surface and boundary systems.
A series of experiments investigated concurrent discriminations of surface and nonsurface attributes, including color, brightness, texture, length, location, and motion. In all cases but one, results matched those previously reported: Interference occurred when two discriminations concerned different objects, but not when they concerned the same one. In the two-object case, interference was the same whether discriminations were similar (e.g., two surface discriminations) or different (e.g., one surface, one boundary). Such results support a model of visual attention in which separate visual subsystems are coordinated, converging to work on surface and boundary properties of the same selected object. A partial exception is color: For reasons that are unclear, color escapes two-object interference except from other, concurrent surface discriminations.
Duncan
J
J
MRC Applied Psychology Unit, Cambridge, England. john.duncan@mrc-apu.cam.ac.uk
Nimmo-Smith
I
I
D000328:Adult; D001288:Attention; D003118:Color Perception; D015350:Contrast Sensitivity; D004193:Discrimination Learning; D005260:Female; D005364:Field Dependence-Independence; D006801:Humans; D008297:Male; D009039:Motion Perception; D009949:Orientation; D010364:Pattern Recognition, Visual; D011601:Psychophysics; D012858:Size Perception