Abstract
A critical function of attention is to direct focus to salient stimuli in the environment. The "saliency" of a stimulus is sometimes defined by basic physical attributes (e.g., high contrast visual feature), but attentional biases may also be driven by more complex sets of features and characteristics. Such highly salient stimuli can capture and potentially hold attention, leading to distraction. The mechanisms by which highly salient, yet irrelevant, stimuli lead to distraction, however, are not well understood. Here, we investigated how a particularly strong type of distractor - images of human faces expressing fear - involuntarily bias attention. Across three experiments using a novel continuous performance task and behavioral measures of accuracy and reaction time, we find that increased distraction is not associated with an enhanced attraction to faces, but instead reflects an extended hold of attention on faces. Specifically, the initial onset of a distractor impaired target performance regardless of the identity of that distractor (i.e., picture of a face or picture of a place). In contrast, an extended period of distraction was observed only when the distractor was a face. Whereas previous work has highlighted the human tendency to preferentially attend to faces, the current results refine the mechanism by which this unique bias may occur: an extended dwelling of attention on faces. Critically, however, the holding of attention by faces was not dependent on the emotional expression on the face, occurring for neutral faces as well as for fearful faces. Furthermore, whereas the initial capture of attention to the sudden onset of a distractor occurred regardless of context (i.e., consistent distractor type vs. mixed distractor type), the presence of an extended holding of attention was dependent on the ongoing distractor context, providing further evidence to dissociate reflexive capture and attentional hold.
Meeting abstract presented at VSS 2013