Abstract
Previous research has demonstrated that individuals are capable of remembering some identity information about task irrelevant distractors during visual search, although performance is not at ceiling even when the distractor was fixated just before the memory test. Memory for distractors may be improved in hybrid search because, individuals look at distractors longer when the target memory set size is large. Additionally, memory for distractors may be improved when they are semantically related to the target because items that are semantically related to target may also be processed more. Participants in Experiment 1 encoded 1 or 32 target items for 3s each, followed by a search task. On a subset of trials, search ceased after the 4th, 5th, or 6th fixation and was replaced with a two-alternative forced choice (2AFC) test for the identity of distractors that had been previously fixated during the previous search array. In Experiment 2 participants encoded either 6 target items from distinct categories or 30 items with 5 items from 6 categories (i.e., 5 dogs, 5 bikes, etc.) and the search arrays could include distractors that were from the same or different categories as the target items. Eye movement data in Experiment 1 revealed evidence for more processing of distractors (i.e., longer dwell time, more revisits) with a higher target memory set size but explicit memory for distractors did not differ between target memory set sizes. In Experiment 2, there was evidence for more processing of distractors with a higher target memory set size and for semantically related arrays. However, explicit memory for distractors was best when target memory set size was high and the arrays were semantically distinct. Overall these results suggest that hybrid search can improve memory for distractors if the distractors and targets are not semantically related.