Nonconscious perception and information-processing in a visual reaction time task using a backward masking paradigm

本研究探讨了无意识知觉和运动反应的信息处理本质。我们进行了几个实验，使用反应时间（RT）任务（1）与双刺激呈现（即，一个前/启动和以下/目标simuli），以引起元对比或向后掩蔽和（2）使用手指抬起和瞄准运动作为对命令性刺激的反应。在元对比实验中，我们操纵SOA（刺激起始时间）为40 ms（40 ms-SOA），其中前一个刺激的感觉被随后的刺激完全掩盖，或更长的时间（阈值SOA），导致前一个刺激几乎被掩盖。结果表明，RT和意识的前面的刺激被改变以不同的方式彼此为40毫秒和阈值SOA。这表明，运动反应的信息处理可能独立地与信息处理并行发生， ...更多信息 g感知觉。我们还进行了体感后掩蔽实验，操纵前面的刺激的强度，以设置感官敏感性刺激的阈值水平，1.2倍和2阈值。RT和知觉的意识改变彼此独立的刺激强度，表明相同的结果，在元对比实验。在实验中使用手指抬起和瞄准任务，我们操纵的大小，亮度对比度和位置的视觉刺激。通过从瞄准任务中减去手指抬起的RT计算出的RT差异仅作为呈现位点的函数而改变。这表明，运动反应是直接相关的空间，而不是所呈现的刺激的物理性质的看法。总的来说，本研究项目的这些发现表明，运动反应的信息处理不会发生在感知刺激的基础上，并且运动反应和感知意识的产生所依赖的两种信息处理可能会被并行激活。虽然我们在这些实验中测量了EEG，但EEG数据无法有效解释无意识感知和运动反应。这些问题应在今后的研究项目中进一步研究。少

This research project examined the nature of information processing underlying perception without awareness and motor responses. We conducted several experiments using reaction time (RT) tasks (1) with double-stimulus presentations (i.e., a preceding/prime and the following/target simuli) to cause either metacontrast or backward-masking and (2) using finger-lift and aiming movements as responses to imperative stimuli. In the metacontrast experiment we manipulated SOAs (stimulus onset asynchrony) to be either 40ms (40ms-SOA), in which the sensation of a preceding stimulus was completely masked by the following stimulus, or much longer time (threshold-SOA) which resulted in the preceding stimulus being nearly masked. Results showed that RTs and awareness of the preceding stimuli were altered in a different way to each other for the 40ms- and threshold-SOAs. This suggests that information processing for motor responses may independently occur in parallel with information processing causin … More g awareness of perception. We also conducted a somatosensory backward-masking experiment, manipulating the intensity of preceding stimulus so as to set sensory sensitivity to stimuli at either a threshold level, 1.2 times and 2 of the threshold. RTs and the awareness of perception altered independently to each other for the stimulus intensities, indicating the same findings as those in the metacontrast experiment. In the experiment using finger-lift and aiming tasks we manipulated the size, luminance contrast, and location of visual stimuli. Differences in RTs calculated by subtracting RTs for the finger-lift from those for aiming tasks altered as a function of presentation loci alone. This suggests that motor response is directly correlated to the perception of spatial rather than physical nature of presented stimuli. Collectively, these findings of this research project suggest that information processing for motor response does not occur on the basis of the awareness of perceived stimuli and that both types of information processing underlying the production of motor response and awareness of perception may well be activated in parallel. Although we measured EEG throughout these experiments, the EEG data could not result in effective explanations of nonconscious perception and motor responses. These issues should be further examined in the future research projects. Less