Tikhonov Alexander, Haarmeier Thomas, Thier Peter, Braun Christoph, Lutzenberger Werner
Department of Cognitive Neurology, University of Tübingen, D-72076 Tuebingen, Germany.
Neuroimage. 2004 Feb;21(2):593-600. doi: 10.1016/j.neuroimage.2003.09.045.
We usually perceive a stationary, stable world despite coherent visual motion induced by eye movements. This astonishing example of perceptual invariance results from a comparison of visual information with internal reference signals (nonretinal signals) predicting the visual consequences of an eye movement. The important consequence of this concept is that our subjective percept of visual motion reflects the outcome of this comparison rather than retinal image slip. To localize the cortical networks underlying this comparison, we compared magnetoencephalography (MEG) responses under two conditions of pursuit-induced retinal image motion, which were identical physically but--due to different calibrational states of the nonretinal signal prompted under our experimental conditions--gave rise to different percepts of visual motion. This approach allows us to demonstrate that our perception of self-induced visual motion resides in comparably "late" parts of the cortical hierarchy of motion processing sparing the early stages up to cortical area MT/V5 but including cortex in and around the medial aspect of the parietooccipital cortex as one of its core elements.
尽管眼球运动可诱发连贯的视觉运动，但我们通常感知到的是一个静止、稳定的世界。这种惊人的知觉不变性示例源于将视觉信息与预测眼球运动视觉后果的内部参考信号（非视网膜信号）进行比较。这一概念的重要结果是，我们对视觉运动的主观感知反映的是这种比较的结果，而非视网膜图像的滑动。为了定位这种比较背后的皮层网络，我们比较了在两种追踪诱发视网膜图像运动条件下的脑磁图（MEG）反应，这两种条件在物理上是相同的，但由于我们实验条件下所激发的非视网膜信号的校准状态不同，产生了不同的视觉运动感知。这种方法使我们能够证明，我们对自我诱发视觉运动的感知存在于运动处理皮层层级中相对“较晚”的部分，早期阶段直至皮层区域MT/V5被排除在外，但包括顶枕叶皮层内侧及其周围的皮层作为其核心要素之一。
