Purchase this article with an account.
Jan W. Brascamp, Tomas H. J. Knapen, Ryota Kanai, Raymond van Ee, Albert V. van den Berg; Flash suppression and flash facilitation in binocular rivalry. Journal of Vision 2007;7(12):12. doi: 10.1167/7.12.12.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
We show that previewing one half image of a binocular rivalry pair can cause it to gain initial dominance when the other half is added, a novel phenomenon we term flash facilitation. This is the converse of a known effect called flash suppression, where the previewed image becomes suppressed upon rivalrous presentation. The exact effect of previewing an image depends on both the duration and the contrast of the prior stimulus. Brief, low-contrast prior stimuli facilitate, whereas long, high-contrast ones suppress. These effects have both an eye-based component and a pattern-based component. Our results suggest that, instead of reflecting two unrelated mechanisms, both facilitation and suppression are manifestations of a single process that occurs progressively during presentation of the prior stimulus. The distinction between the two phenomena would then lie in the extent to which the process has developed during prior stimulation. This view is consistent with a neural model previously proposed to account for perceptual stabilization of ambiguous stimuli, suggesting a relation between perceptual stabilization and the present phenomena.
Time course of a trial in the main condition. Subjects consecutively viewed one half of a dichoptic orthogonal grating stimulus (prior stimulus), a blank interval, and both stimulus halves together (test). They then reported which of the two rivaling orientations was perceptually dominant during the test, revealing effects of the prior stimulus. We systematically varied the durations of the prior stimulus and the blank, as shown, as well as the contrast of the prior stimulus. In additional conditions, we varied the nature of the prior stimulus to specifically address eye-based and pattern-based effects and to investigate the importance of the spatial correspondence between prior stimulus and test stimulus. We also varied the luminance of the background to investigate if the relative luminance of the stimulus with respect to its surround affects the observed effects.
This PDF is available to Subscribers Only