The aim of this study was to determine if flash suppression for contour rivalry consisted of two subsequent stages that might be influenced by the observer's perceptual experience. Participant exposure to primes involved either simultaneous delivery of a grating among orthogonal gratings to both eyes (binocular priming) or to one eye alone (monocular priming) for I s. Interstimulus intervals (ISIS) of 0-2000 ms followed the prime, with rival target gratings then simultaneously presented to both eyes for 10-200 ms. When a stimulus-offset asynchrony (SOFFA) of <50 ms was used, the dominant percept to binocular priming was a fusion of the targets. The transfer of the monocular priming suppression to the other eye was found to be difficult. For a SOFFA >50 ms, observers dominantly perceived the unprimed target. With this selective effect, interocular transfer was noted for the monocular priming. When brief targets (10 ms) were employed, two temporal stages with less individuality were detected. When longer targets (200 ins) were used during the monocular priming, the experienced observers were better at preserving the visibility as compared to the naive observers.

Key words: flash suppression, orientation, priming, binocular rivalry