A calm eye is associated with the passive advantage in visual search

Visual search can be more efficient when one views a display passively, allowing the target to pop into view, than when one actively directs attention around a display in a deliberate effort to locate a target (Smilek et al., 2006). However, little is known about why these different cognitive strategies lead to differences in performance. One possibility is that patterns of eye movements also differ with strategy, such that eye movements associated with the passive strategy allow search items to be registered in a more efficient way. Alternatively, the advantage of a passive strategy may accrue from processes that occur only after the search items have been registered, in which case one would not expect any differences in eye movements between the two strategies. In the experiments reported here, we monitored participants' gaze while they performed visual search tasks of varying difficulty after having been instructed to use either an active or a passive strategy. The passive strategy led to greater search efficiency (speed and accuracy) at all difficulty levels, which suggests that cognitive strategy may have even more influence on search performance than previously observed (Smilek et al., 2006). Furthermore, eye movement data showed that this passive advantage is correlated with fewer saccades per second and longer fixation durations. More detailed analyses examined differences in fixation location in the two conditions, and individual differences in eye movements independent of strategy. These findings are consistent with the hypothesis that the passive advantage in visual search is associated with a calmer eye.