Postattentive vision

Much research has examined preattentive vision: visual representation prior to the arrival of attention. Most vision research concerns attended visual stimuli; very little research has considered postattentive vision. What is the visual representation of a previously attended object once attention i s deployed elsewhere? The authors argue that perceptual effects of attentio n vanish once attention is redeployed. Experiments la were visual search st udies. In standard search, participants looked for a target item among dist racter items. On each trial, a new search display was presented. These task s were compared to repeated search tasks in which the search display was no t changed. On successive trials, participants searched the same display for new targets. Results showed that if search was inefficient when participan ts searched a display the first time, it was inefficient when the same, unc hanging display was searched the second, fifth, or 350th time. Experiments 7 and 8 made a similar point with a curve tracing paradigm. The results hav e implications for an understanding of scene perception, change detection, and the relationship of vision to memory.