Exploring the roles of distinctiveness and performance anticipation in the Attentional Boost Effect.

We tested the validity of two alternative accounts of the Attentional Boost Effect (ABE) - the finding that words associated with to-be-responded targets are recognized better than words associated with to-be-ignored distractors. The hypothesis assumes that, during recognition, participants probe their memories for distinctive information confirming that a word was studied (e.g., "I remember having pressed the spacebar, so I must have studied the word"). This strategy cannot be used in a between-subjects condition in which participants cannot appreciate the differences between target - and distractor-paired words. In agreement, Experiments 1A and 1B found that the ABE was significant in a within-subjects design, whereas it was eliminated in a between-subjects design. On the other hand, the hypothesis assumes that, during the study phase, participants anticipate the need of responding to a subset of target-paired words: this would create a persistent performance anticipation that would prevent them from effectively encoding distractor-paired words. In contrast with this account, we found that, when blocks of five distractor trials were regularly alternated with blocks of five target trials in Experiment 2, recognition accuracy decreased linearly in both conditions. Overall, these results suggest that distinctiveness, but not performance anticipation, might underlie the ABE.