Huang Changzhi, Jiang Rong, Meng Ming
Key Laboratory of Brain, Cognition and Education Sciences, Ministry of Education, School of Psychology, South China Normal University, Guangzhou, China.
Center for Studies of Psychological Application, Guangdong Key Laboratory of Mental Health and Cognitive Science, School of Psychology, South China Normal University, Guangzhou, China.
J Vis. 2025 Aug 1;25(10):14. doi: 10.1167/jov.25.10.14.
The human visual system prioritizes dynamic stimuli, which attract attention and more readily break suppression to reach perceptual awareness. Here, we investigated whether dynamic changes in contrast-either increasing or decreasing-are equally effective in facilitating the breakthrough of suppressed stimuli during binocular rivalry. In Experiment 1a, we found that contrast increases led to significantly faster breakthroughs into perceptual dominance compared with decreases. Notably, increases accelerated breakthrough relative to the unchanged baseline, whereas decreases delayed it. Experiments 1b and 1c replicated the results of Experiment 1a using, respectively, a briefer contrast change (10 ms instead of 100 ms) and partial breakthrough reports, confirming a robust asymmetry in the processing of suppressed stimuli between increases and decreases. In Experiment 2a, random dots moving in different random directions were presented dichoptically, making interocular conflict imperceptible and unreportable. We found that any change in intensity in such rivalry settings-regardless of increase or decrease-promoted perceptual dominance. By introducing motion stimuli into the Experiment 1 paradigm, Experiment 2b demonstrated that the divergence between Experiments 1 and 2 was not due to low-level stimulus differences. Taken together, our results reveal an asymmetric effect of contrast changes during binocular rivalry. This finding highlights the interplay between subliminal sensory processing of contrast changes and conscious awareness, shedding light on developing theoretical models of binocular rivalry.
人类视觉系统优先处理动态刺激，这类刺激会吸引注意力，并更容易打破抑制以达到感知觉意识。在此，我们研究了对比度的动态变化（增加或减少）在双眼竞争过程中促进被抑制刺激突破方面是否同样有效。在实验1a中，我们发现与对比度降低相比，对比度增加导致进入感知优势的突破明显更快。值得注意的是，相对于不变的基线，增加加速了突破，而降低则延迟了突破。实验1b和1c分别使用更短暂的对比度变化（10毫秒而非100毫秒）和部分突破报告重复了实验1a的结果，证实了在处理被抑制刺激时增加和减少之间存在强烈的不对称性。在实验2a中，以双眼分视的方式呈现朝不同随机方向移动的随机点，使双眼冲突不可察觉且无法报告。我们发现，在这种竞争情境下，强度的任何变化（无论增加还是减少）都会促进感知优势。通过将运动刺激引入实验1范式，实验2b表明实验1和实验2之间的差异并非由于低水平的刺激差异。综合来看，我们的结果揭示了双眼竞争期间对比度变化的不对称效应。这一发现凸显了对比度变化的阈下感觉处理与意识觉知之间的相互作用，为发展双眼竞争的理论模型提供了线索。
