Visual Search and Dual Tasks Reveal Two Distinct Attentional Resources
- Creators
- VanRullen, Rufin
- Reddy, Lavanya
- Koch, Christof
Abstract
Most theories of visual processing assume that a target will "pop out" from an array of distractors ("parallel" visual search, e.g., color or orientation discrimination) if targets and distractors can be discriminated without attention. When the discrimination requires attention (e.g., rotated L vs. T or red-green vs. green-red bisected disks), "serial" examination is needed in visual search. Attentional requirements are also frequently assessed by measuring interference from a concurrently performed attentionally demanding task. It is commonly believed that attention acts equivalently in dual-task and visual search paradigms, based on the implicit assumption that visual attentional requirements can be defined along a single dimension. Here we show that there is no such equivalence: We report on targets that do not trigger pop-out, even though they can be discriminated from distractors with attention occupied elsewhere (natural scenes, color-orientation conjunctions); conversely, we show that certain targets that pop out among distractors need undivided attention to be effectively discriminated from distractors when presented in isolation (rotated L vs. +, depth-rotated cubes). In other words, visual search and dual-task performance reveal attentional resources along two independent dimensions. We suggest an interpretation of these results in terms of neuronal selectivities and receptive field size effects.
Additional Information
© 2004 Massachusetts Institute of Technology. Posted Online March 13, 2006. This research was supported by grants from the NSF sponsored Engineering research Center at Caltech, the National Institutes of Health, the Keck Foundation, and the McDonnell Foundation. The authors thank FeiFei Li and Pietro Perona for helpful discussions, and Francis Crick, Anne Treisman, Achim Braun, and Leila Reddy for critical comments on the manuscript.Attached Files
Published - 474.pdf
Files
Name | Size | Download all |
---|---|---|
md5:008f3748ddff1d3e372a916dc9a97391
|
364.6 kB | Preview Download |
Additional details
- Eprint ID
- 40536
- Resolver ID
- CaltechAUTHORS:20130816-103234995
- Center for Neuromorphic Systems Engineering, Caltech
- NIH
- W. M. Keck Foundation
- James S. McDonnell Foundation
- Created
-
2008-01-12Created from EPrint's datestamp field
- Updated
-
2023-04-26Created from EPrint's last_modified field
- Caltech groups
- Koch Laboratory (KLAB)