Effects of implicit learning and explicit knowledge on the spatial suppression of irrelevant distractors

摘要

Previous research in our lab has revealed that ignoring spatial locations that are likely to contain irrelevant, distracting information can be possible with subtle implicit learning manipulations (Leber, Gwinn & O'Toole, 2013, VSS). In that work, observers were unable to avoid interference by irrelevant distractors whose location was predicted by informative explicit spatial precues. However, when implicit spatial precues were introduced, the observers now demonstrated suppression of the irrelevant distractors, despite reporting no awareness of the implicit cues. In the present work, we asked the following: how does explicit knowledge interact with implicit learning in the suppression of irrelevant distractors? Will explicit knowledge prevent the implicit suppression of irrelevant information? To investigate this question, we modified our procedure using explicit dual arrow precues, which were presented simultaneously. In Experiment 1, a long arrow cued the most likely location of the target while a short arrow cued the most likely location of the distractor, both with 70% validity. Also, the same arrow that explicitly predicted the target location also implicitly predicted the distractor location with 70% validity. We found a robust target validity effect, demonstrating that observers used the long arrow to enhance the predicted target location. Critically, we also found a distractor validity effect, suggesting that implicit learning could occur in the presence of explicit cues. A second experiment confirmed that the suppression was selectively driven by the implicit cue; here, explicit dual cues were again used but now the implicit distractor cue was removed. Results again showed a robust target validity effect, but critically, the distractor validity effect did not emerge. Thus, while spatial suppression tends to occur only in the presence of implicit cues, simultaneous explicit cues a?? which are typically ignored a?? do not seem to interfere with or counteract the implicit learning effect.