Abstract
In the increasing consideration of biological relevance to perception, stimuli such as spiders, angry faces, and even animate objects categorically (humans and nonhuman animals) have proven robustly capable of capturing visual attention. We examined how increased attention to one such category, animate objects, may also augment their representation in visual awareness. We proposed that such an enhanced representation could be experienced as having a subjectively prolonged duration (exceeding its physical duration), termed subjective time dilation. We predicted that the duration of briefly-displayed people and animals (both previously shown to be prioritized for visual attention) will more often than inanimate objects appear greater than their veridical duration. We tested this prediction with the ‘oddball’ paradigm: the duration of an attention-capturing stimulus in an image series often appears longer than the other stimuli, even when displayed for less time than the other images all shown for the ‘standard’ duration. One item from one natural category (people, animals, flowers, or vehicles) was presented amongst urban and rural landscapes and ranged in duration from half to slightly longer than the standard duration. Participants simply identified which item in each stream of images was displayed for a ‘longer’ amount of time than the others. Animate objects were identified as the ‘longer’ images in the sequences far more frequently than chance –and significantly more frequently than the inanimate targets – even when presented for 50% of the standard duration. Additional experiments ruled out that the subjectively prolonged duration of animate objects resulted from differences in lower-level visual characteristics or dissimilarities from the distractor images. Brief glimpses of biologically relevant objects may thus be more persistently represented in visual awareness than other types of objects. These studies additionally demonstrate how subjective time dilation and duration estimation can be employed as a novel and implicit metric of attentional capture.
Meeting abstract presented at VSS 2012