Abstract
Visual attention can be deployed across space or time, potentially altering the appearance or probability of perceiving stimuli. Carrasco, Ling, & Read (2004) showed that spatial attention increased the perceived contrast of Gabor patches, whereas Asplund et al. (2014) showed that temporal attention affected only the probability of perceiving a color or face target in the attentional blink. Here we adopted Carrasco et al.'s psychophysical approach and stimuli to test whether temporal attention--altered either with cues or the attentional blink--could also have graded effects on conscious perception. After replicating the spatial attention findings, we used rapid serial visual presentation (RSVP) streams of Gabor patches to explore the effects of temporal attention. On each trial, participants reported how many obliquely angled, target Gabor patches were present (0, 1, or 2), and, when two were reported, which patch had the higher contrast. In a temporal cueing experiment, four-dot cues presented 120 ms before one of the targets increased its perceived contrast. In an attentional blink experiment, however, lag (3 or 8) affected only the number of perceived Gabors, not their relative perceived contrasts. These findings support the idea that different forms of attention can affect perception in a graded fashion, particularly at earlier stages of visual processing. By contrast, the attentional blink represents a limitation at central stages of visual cognition, where conscious perception emerges in an all-or-none fashion.
Meeting abstract presented at VSS 2017