Department of Fundamental Neuroscience, University of Geneva, Geneva, Switzerland.
Hum Brain Mapp. 2011 Sep;32(9):1432-42. doi: 10.1002/hbm.21117. Epub 2010 Aug 5.
We investigated perceptual reversals for intermittently presented stimuli during binocular rivalry and physical alternation while the ongoing EEG was recorded from 64 channels. EEG topographies immediately preceding stimulus-onset were analyzed and two topographies doubly dissociated perceptual reversals from non-reversals. The estimated intracranial generators associated with these topographies were stronger in right inferior parietal cortex and weaker bilaterally in the ventral stream before perceptual reversals. No such differences were found for physical alternation of the same stimuli. These results replicate and extend findings from a previous study with the Necker cube and suggest common neural mechanisms associated with perceptual reversals during binocular rivalry and ambiguous figure perception. For both types of multi-stable stimuli, the dorsal stream is more active preceding perceptual reversals. Activity in the ventral stream, however, differed for binocular rivalry compared to ambiguous figures. The results from the two studies suggest a causal role for the right inferior parietal cortex in generating perceptual reversals regardless of the type of multi-stable stimulus, while activity in the ventral stream appears to depend on the particular type of stimulus.
我们在双眼竞争和物理交替期间间歇性呈现刺激时，记录了来自 64 个通道的脑电图，并研究了知觉反转。在刺激开始前，分析了脑电图地形图，并通过两种地形图将知觉反转与非反转区分开来。在知觉反转之前，与这些地形图相关的估计颅内发生器在右下顶叶皮层更强，而在腹侧流中双侧较弱。对于相同刺激的物理交替，没有发现这种差异。这些结果复制并扩展了之前使用内克尔立方体的研究结果，并表明与双眼竞争和模棱两可图形感知期间的知觉反转相关的共同神经机制。对于这两种类型的多稳态刺激，在知觉反转之前，背侧流的活动更活跃。然而，与双眼竞争相比，腹侧流的活动在模棱两可的图形中有所不同。这两项研究的结果表明，无论多稳态刺激的类型如何，右顶下叶皮层在产生知觉反转方面都起着因果作用，而腹侧流的活动似乎取决于特定的刺激类型。
