Abstract
It is generally accepted that low-level visual properties such as orientation and color can be processed subliminally to a great extent. However, whether complex information integration can be processed subliminally remains controversial. It is possible that high-order information processing requires stronger subliminal signals that cannot be easily achieved with conventional masking paradigms. For instance, although a thresholding procedure is usually used to obtain the "barely visible" level of signal strength (sub-threshold contrast level), the optimal duration of a subliminal stimulus has rarely been manipulated to achieve optimal signal strength. Here we report a novel form of continuous flash suppression (CFS) that allows longer subliminal presentation: dis-continuous flash suppression (DCFS), in which both the stimulus and the suppressor are presented discontinuously (in a repeated on-and-off manner) to achieve stronger suppression power. In Experiment 1, we found that compared with CFS, given same broken rates, DCFS allowed approximately 50% higher contrast of the stimulus. As for the suppression time, given the same contrast, DCFS allows 50% longer suppression time. In Experiment 2, we further utilized DCFS to examine whether temporal integration of linguistic information occurs while the stimuli were suppressed and remained unconscious. Our results showed that after an invisible 2-word sentence context, the response time of the lexical decision to the following syntactically incongruent word was significantly faster than that to a congruent word. Taken together, we report a novel form of interocular suppression named dis-continuous flash suppression, which allows longer subliminal presentation and may help researchers to lengthen the presentation duration to increase subliminal signals. Furthermore, we show that temporal integration occurs without the stimulus being consciously perceived under DCFS.
Meeting abstract presented at VSS 2018