Spatial attention improves performance in spatial resolution tasks1Parts of this study were presented at the Annual Meeting of the Association for Research in Vision and Ophthalmology (May 1997) and at the Annual Meeting of the Psychonomics Society (November 1997) and published in Abstract format (Yeshurun and Carrasco, 1997and Carrasco and Yeshurun, 1997, respectively).1

This study used peripheral precueing to explore the effect of covert transient attention on performance in spatial resolution tasks. Experiments 1 (Landolt-square) and 2 (‘broken-line’) measured gap resolution and Experiment 3 measured vernier resolution. In all three tasks the target was presented alone in a large number of possible locations, ranging from 1.5–6° of eccentricity in the vertical or horizontal axes. The precue indicated the target location but did not convey information regarding the correct response. Performance decreased as the gap size or the vernier offset size decreased and as target eccentricity increased. Precueing improved performance in terms of RT and accuracy in all three tasks; the eccentricity effect decreased in the cued trials of the gap resolution tasks. These findings support the idea that the performance improvement at attended locations results, to some extent, from an enhanced spatial resolution at the cued location, and not just from distractor exclusion, diminished uncertainty, or decisional factors. © 1998 Elsevier Science Ltd. All rights reserved.