Continuous flash suppression (CFS)
A visual-psychophysics technique for rendering a stimulus invisible for a sustained period, used to study what the brain processes outside of awareness. A rapidly changing high-contrast pattern (“Mondrians”) is flashed to the dominant eye; a target presented to the other eye is suppressed from consciousness by the interocular competition. Because the suppression lasts seconds — much longer than binocular rivalry or backward masking — CFS is the workhorse for asking whether invisible stimuli are still processed, and how fast different stimuli “break through.”
Breaking CFS (b-CFS) uses the time to emergence as the dependent measure: a stimulus that reaches awareness faster is treated as having privileged access. Emotional faces, one’s own name, and semantically congruent images all break suppression faster than their controls.
In this wiki
- Salomon et al. (2016) used b-CFS to show that a visual target flashed synchronously with the viewer’s own heartbeat takes longer to break suppression than an asynchronous one — interoceptive timing suppressing exteroceptive awareness. Crucially, they also ran a full-suppression fMRI version (the target never becomes visible) to localize the effect in the anterior insula independent of time-to-emergence, and a classic non-suppression CFS control (target blended into both eyes) to rule out a response/detection bias.
Caveats the wiki cares about
The breaking-CFS measure is contested: a “faster breakthrough” can be a difference in low-level detectability or in post-perceptual decision rather than in genuine unconscious processing (Stein et al. 2011; Yang et al. 2014). Studies that lean on it are stronger when — as in Salomon et al. — they pair it with a full-suppression measure and a converging paradigm that does not use time-to-emergence (there, visual-crowding).