Cutting through the MADness: Expectations about what a target is doing impact how likely it is to be found in dynamic visual displays

When searching for things in the world, we seldom encounter the static environment so often afforded by laboratory search tasks. Dynamic events tend to capture attention; however, Kunar and Watson previously found that dynamic search displays (search for vowel targets among moving and blinking letter stimuli) resulted in strikingly high miss rates. A possible explanation for the high miss rates is that the presence of dynamic features resulted in participants becoming sensitive to the likelihood of appearance for each target category and dynamic feature combination (e.g., moving A, blinking A, moving E), even though dynamic features did not define the targets. Overall target prevalence was high in these studies, but the prevalence of each target + dynamic feature combination was low, which may have led to a low-prevalence effect, whereby infrequent targets were disproportionately missed. Searchers may have preferentially searched for (or avoided) certain dynamic features, even though the dynamic features did not differentiate targets from distractors. We investigated whether the frequency with which targets possessed particular dynamic features would affect the likelihood of search misses. We found that targets possessing features which rarely accompanied a “hit” were more often missed than those with dynamic features more strongly associated with target detection. This suggests that searchers are sensitive to the prevalence of non-defining features and use this information to direct their searches.