Sporns O, Tononi G, Edelman G M
Neurosciences Institute, New York, NY 10021.
Proc Natl Acad Sci U S A. 1991 Jan 1;88(1):129-33. doi: 10.1073/pnas.88.1.129.
The segmentation of visual scenes is a fundamental process of early vision, but the underlying neural mechanisms are still largely unknown. Theoretical considerations as well as neurophysiological findings point to the importance in such processes of temporal correlations in neuronal activity. In a previous model, we showed that reentrant signaling among rhythmically active neuronal groups can correlate responses along spatially extended contours. We now have modified and extended this model to address the problems of perceptual grouping and figure-ground segregation in vision. A novel feature is that the efficacy of the connections is allowed to change on a fast time scale. This results in active reentrant connections that amplify the correlations among neuronal groups. The responses of the model are able to link the elements corresponding to a coherent figure and to segregate them from the background or from another figure in a way that is consistent with the so-called Gestalt laws.
视觉场景的分割是早期视觉的一个基本过程，但其潜在的神经机制在很大程度上仍然未知。理论思考以及神经生理学研究结果都表明，神经元活动中的时间相关性在这些过程中具有重要意义。在之前的一个模型中，我们表明有节奏地活跃的神经元群体之间的折返信号可以使沿空间扩展轮廓的反应相关联。我们现在对这个模型进行了修改和扩展，以解决视觉中的感知分组和图形-背景分离问题。一个新的特点是，连接的效能被允许在快速时间尺度上发生变化。这导致了活跃的折返连接，增强了神经元群体之间的相关性。该模型的反应能够将与连贯图形相对应的元素联系起来，并以与所谓的格式塔定律相一致的方式将它们与背景或另一个图形区分开来。
