The effect of expectation on visual consciousness: based on signal detection theory

The experimental material was sinusoidal Gabor patch with a Michelson contrast ratio of 0.03 and a vertical tilt of 45° to the left or right. Blank stimulus was no target. The experimental materials were made from online-gabor-patch-generator. The background brightness of all these types of stimuli was 22cd/m2. The experiment used a 3 (expectation: high/no/low) single-factor experimental design. Expectations were manipulated by the probabilistic information presented by the stimulus, where high expectations were the probability of the stimulus occurring at 75%, no expectations were the probability of the stimulus occurring at 50%, and low expectations were the probability of the stimulus occurring at 25%. Before each block of the experiment, participants were told what proportion of stimuli were present. Experimental stimuli were presented in E-Prime 2.0 software. The resolution of the screen wes 1024x768 pixels, and the screen refresh rate wes 60Hz (1 refresh cycle wes about 17ms). The participants were about 80cm away from the screen. The masking paradigm was used to detect the experimental task first, and then to judge the level of consciousness.