Abstract
Prior work has suggested that information about distractors is encoded from incidental fixations during visual search (Hout & Goldinger, 2001; Williams, Henderson & Zack, 2005). This work has shown that there is better memory for the distractor object identities that are more frequently fixated. All this prior work, however, is based on experiments where targets change on each trial. Does this effect replicate when the target remains the same on each trial? In a different context, evidence from event-related potentials has suggested that the role of working memory decreases when a visual target is repeated across trials (Carlisle et al., 2011). One possibility is that recognition memory for incidental fixations is driven by working memory (WM). If this is the case, we should expect dwell time to be less predictive of later recognition for distractors if a target is repeated because a repeated target will engage long-term memory rather than WM. To test whether a repeated target decreases the benefit in memory gained by incidental fixations we compared two experiments. In Experiment One, participants searched for the same target on every trial. In Experiment Two, targets changed on every trial. Consistent with prior work, we found that greater dwell time on distractors led to increased recognition during a surprise memory test. However, contrary to our predictions, increased dwell time lead to improved recognition memory even when the same target repeated 400 times in row. Even more striking, recognition memory was equivalent across both experiments despite far greater dwell time on distractors when participants searched for a new target on each trial. Overall, we find that the nature of the search does not appear to influence the small, but reliable relationship between incidental fixations and later recognition.
Acknowledgement: DOD: W911NF-07-2-0055 BSF: #2015301