Department of Vision and Cognition, Netherlands Institute for Neuroscience, Meibergdreef 47, 1105 BA Amsterdam, Netherlands.
Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA.
Science. 2018 May 4;360(6388):537-542. doi: 10.1126/science.aar7186. Epub 2018 Mar 22.
Why are some visual stimuli consciously detected, whereas others remain subliminal? We investigated the fate of weak visual stimuli in the visual and frontal cortex of awake monkeys trained to report stimulus presence. Reported stimuli were associated with strong sustained activity in the frontal cortex, and frontal activity was weaker and quickly decayed for unreported stimuli. Information about weak stimuli could be lost at successive stages en route from the visual to the frontal cortex, and these propagation failures were confirmed through microstimulation of area V1. Fluctuations in response bias and sensitivity during perception of identical stimuli were traced back to prestimulus brain-state markers. A model in which stimuli become consciously reportable when they elicit a nonlinear ignition process in higher cortical areas explained our results.
为什么有些视觉刺激是有意识检测到的，而有些则是潜意识的？我们研究了在接受报告刺激存在训练的清醒猴子的视觉和额叶皮层中，弱视觉刺激的命运。报告的刺激与额叶皮层中的强持续活动有关，而未报告的刺激的额叶活动较弱且迅速衰减。关于弱刺激的信息可能会在从视觉到额叶皮层的连续阶段丢失，并且通过对 V1 区的微刺激证实了这些传播失败。在感知相同刺激时，反应偏差和敏感性的波动可以追溯到刺激前的大脑状态标记。当刺激在更高的皮层区域引发非线性点火过程时，刺激就会变得可以有意识地报告，该模型解释了我们的结果。
