Polonsky A, Blake R, Braun J, Heeger D J
Department of Psychology, Jordan Hall, Building 420, Stanford University, Stanford, California 94303, USA.
Nat Neurosci. 2000 Nov;3(11):1153-9. doi: 10.1038/80676.
During binocular rivalry, two incompatible monocular images compete for perceptual dominance, with one pattern temporarily suppressed from conscious awareness. We measured fMRI signals in early visual cortex while subjects viewed rival dichoptic images of two different contrasts; the contrast difference served as a 'tag' for the neuronal representations of the two monocular images. Activity in primary visual cortex (V1) increased when subjects perceived the higher contrast pattern and decreased when subjects perceived the lower contrast pattern. These fluctuations in V1 activity during rivalry were about 55% as large as those evoked by alternately presenting the two monocular images without rivalry. The rivalry-related fluctuations in V1 activity were roughly equal to those observed in other visual areas (V2, V3, V3a and V4v). These results challenge the view that the neuronal mechanisms responsible for binocular rivalry occur primarily in later visual areas.
在双眼竞争期间，两个不相容的单眼图像争夺感知主导权，其中一种模式会暂时从意识中被抑制。当受试者观看具有两种不同对比度的竞争双眼图像时，我们测量了早期视觉皮层中的功能磁共振成像（fMRI）信号；对比度差异作为两种单眼图像神经元表征的“标签”。当受试者感知到较高对比度模式时，初级视觉皮层（V1）的活动增加，而当受试者感知到较低对比度模式时，活动减少。在竞争期间V1活动的这些波动大约是在无竞争情况下交替呈现两种单眼图像所诱发波动的55%。V1活动中与竞争相关的波动大致与在其他视觉区域（V2、V3、V3a和V4v）中观察到的波动相等。这些结果挑战了认为负责双眼竞争的神经元机制主要发生在后期视觉区域的观点。
