The interaction of internal and external attention.

The internal/external framework of attention characterizes attention focused to perceptual stimuli and internal representations as highly similar processes. While much research on external attention examines how attention may be broadened or narrowed (attentional zoom lens), it is unclear if internal attention functions in a similar way. In the present study, we manipulate both internal and external attentions to be either broad or narrow. Participants first encoded either a broad or narrow working memory array containing three differently colored items. This array was maintained as they performed an Eriksen flanker task that was either distributed broadly or narrowly, followed by a memory test for a random memory item. We found that regardless of whether the flanker fell inside or outside of the internal breadth of attention, flanker congruency effects did not change. The exception to this was when internal breadth was manipulated with retrocuing, which resulted in greater congruency effects when flankers aligned with the span of internal breadth rather than falling outside of it. Overall, this study shows that internal breadth information is unlikely to alter processing of external distractors until some of the information is cued internally after encoding, suggesting limitations in the internal/external attention framework.

Typicality modulates the visual awareness of objects.

In the present study, we assessed whether typicality can influence the visual awareness of objects. Participants tracked moving images of objects and counted how often members of one category bounced off the edges of the display. On the last trial, an unexpected object moved across the display. In our first two experiments, this object could belong to the same category as the tracked or untracked objects. While participants were more likely to notice atypical members of the untracked category, this pattern of results reversed when participants tracked atypical objects. In our last two experiments, the unexpected object could belong to the same category as the tracked objects or a new category of objects. In this case, participants were more likely to notice typical members of both the tracked category and the new category. Together, these findings suggest that typicality can modulate the visual awareness of objects.

Typicality modulates attentional capture by object categories.

What we pay attention to in the visual environment is often driven by what we know about the world. For example, a number of studies have found that observers can adopt attentional sets for a particular semantic category. However, some objects are more typical members of a category than others. While previous evidence suggests that an object's typicality can influence the guidance of attention in visual search, it is unclear whether typicality can also influence the capture of attention. To test whether this is the case, participants were given a category of objects at the beginning of each trial. Then, a rapid serial visual presentation (RSVP) stream was presented at fixation, and participants had to indicate whether an object of the given category was present or absent from the stream. Importantly, a single flanker image also appeared above or below the central stream just before the target. This flanker could belong either to the same category as the target or a different category, and could be a typical or atypical exemplar of that category. Participants were less accurate at detecting the target when the flanker belonged to the same category as the target. Moreover, participants were even less accurate when the flanker was a typical exemplar of this category. Similar findings were observed when targets consisted of typical and atypical exemplars. Together, these findings indicate that the extent of attentional capture toward a distractor depends on whether the distractor matches the category and typicality of one's attentional set.