Attentional guidance in singleton search: An examination of top-down, bottom-up, and intertrial factors

Abstract

While it is clear that the goals of an observer change behaviour, their role in the guidance of visual attention has been much debated. In particular, there has been controversy over whether top-down knowledge can influence attentional guidance in search for a singleton item that is already salient by a bottom-up account (Theeuwes, Reimann, & Mortier, 2006). One suggestion is that passive intertrial priming accounts for what has been called top-down guidance (e.g., Maljkovic & Nakayama, 1994). In the present study, participants responded to the shape of a singleton target among homogenous distractors in a trial-by-trial cueing design. We examined the influence of target expectancy, trial history, and target salience (which was manipulated by changing the number of distractors). Top-down influence resulted in fast RTs that were independent of display size, even on trials that received no priming. Our findings show there is a role for top-down guidance, even in singleton search. The designation of intertrial priming as a bottom-up factor, rather than an implicit top-down factor (Wolfe, Butcher, Lee, & Hyle, 2003), is also discussed.

Acknowledgements

This work was supported by an NIH training grant EY07143 to CJL. Thanks go to Chip Folk, Andrew Leber, Amy Shelton, and Steve Yantis, as well as Brian Goolsby, Chris Olivers, Jeremy Wolfe, and an anonymous reviewer for helpful comments on the manuscript.

Notes

¹The cues indicated the dimension of the upcoming target singleton, but this was always associated with a particular feature (e.g., a “shape” cue always indicated the target would be a green diamond among the green circle distractors). Because of this, it is not entirely clear whether this should be thought of as feature or dimensional cueing.

²In contrast, the results of Bravo and Nakayama (1992) did suggest that even with large display sizes (over 20 items), there was faster performance in the target-known condition. However, since they used consistent versus inconsistent blocks to manipulate target knowledge, it is unclear whether this remaining benefit is attributable to priming differences.

³Pinto, Olivers, and Theeuwes (2005) found that distractor interference was reduced on repeat trials, a seemingly contradictory result. However, this discrepancy may be due to their design, in which the distractor and no distractor conditions were blocked, rather than intertrial effects (see Lamy et al., 2006, p. 929 for a more detailed discussion).