Theories of attention can be separated into those that select by location, and those that select by location-invariant representation. Experiments demonstrating stronger interference or facilitation from distractors grouped by nonspatial features with the target than ungrouped distractors have been considered as evidence for the selection of location-invariant representations. However, few studies have measured spatial attention directly at the locations of the grouped or ungrouped objects. In these experiments subjects responded to spatial probes (dots) while also identifying a cued target letter among distractors. Probe responses were faster for distractor locations with the target color than for those with the nontarget color, implying that target-color locations receive more attention. This pattern of spatial attention may explain why target-color distractors interfere more with target identification than nontarget-color distractors. These results suggest that although attention can be directed by nonspatial properties such as grouping by color or organization of the scene into objects, selection may ultimately be based on location.
Bibliographical noteFunding Information:
Thanks to Amy Coombs for help in testing subjects, and to Narcisse Bichot, Randolph Blake, Carolyn Cave, Keith Clayton, Nancy Kanwisher, Joe Lappin, Alan Peters, Adam Reeves, Lynn Robertson, Jeff Schall, and Shui-I Shih for helpful suggestions. This work was supported in part by NEI grant EY 08126 to the Vanderbilt Vision Research Center, and by the Brain Science and Engineering Research Program sponsored by the Korean Ministry of Science and Technology to the first author. These data were presented at the Annual Meeting of The Association for Research in Vision and Ophthalmology (ARVO), 1996, , April, Fort Lauderdale, FL.
All Science Journal Classification (ASJC) codes
- Sensory Systems