Abstract
In day-to-day visual search tasks, we may search for instances of multiple types of targets (e.g., searching for specific road signs while also scanning for pedestrians, animals, and traffic cones). In the lab, the “mixed hybrid search task” is a model system developed to study such tasks, where you are looking for general categories of items (e.g., things you don’t want to hit with your car) alongside specific items (e.g., the sign for your exit). Previous hybrid visual search studies have shown that observers are much more likely to miss more general “categorical” targets than specific targets, even though it is quite clear that categorical and specific items are equally likely to be attended in this paradigm. If an item is attended but missed, do observers have any access to the information that may have been accumulating about that target? Twelve participants searched arrays for two specific items (e.g., this shoe and this table) while also searching for unambiguous instances of two categorical target types (e.g., ANY animal and ANY car). In order to look for the existence of sub-threshold information about missed targets, we borrowed methods from the inattentional blindness literature. We asked two, 2AFC questions after every miss error and after 5% of target-absent trials. Question 1: Do you think you missed an item? Question 2: If you did miss something, which of these two items was it? On trials where participants asserted that they had NOT missed an item (“No” to question one), participants correctly selected the right item ~63% of the time against a 50% chance level (p<0.018). Interestingly, this ability to identify the missed target was only seen following missed categorical targets, not missed specific targets. Knowledge about the target’s identity can lurk behind after that target is missed.