Lateral interactions in visual cortex.
Lateral interactions in visual cortex.
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DOI：
10.1101/sqb.1990.055.01.063
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发表时间：
1990
期刊：
影响因子：
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通讯作者：
C. D. Gilbert;Daniel Y. Ts'o;Torsten Wiesel
中科院分区：
文献类型：
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作者：
C. D. Gilbert;Daniel Y. Ts'o;Torsten Wiesel
这些研究中提出的关于初级视觉皮质处理机制的研究结果与最初的观点不同。我们不认为感受场的范围是有限的，而是图像成分的整合过程发生在沿着视觉通路的很晚的阶段，我们已经证明了整合过程是一个渐进的过程，从初级视觉皮质开始(或者甚至更早)，并在一系列聚合和发散的级联连接中建立起来。显然，单元格的过滤特性是动态的，并且可以根据提供特性的上下文进行修改，而不是认为单元格的过滤特性是固定的。最后，我们发现，在婴儿期结束的关键时期之后，大脑皮质的功能结构是固定的，而不是具有固定的功能结构的皮质，而是扰乱系统可以导致长期的地形重组。背景相互作用的其他例子已经在运动子模式中展示，其中细胞的方向选择性被周围的运动的存在所调制(Allman等人。1985年；Tanaka et al.1986年；Gulyas等人。1987；Orban et al.1987)。在颜色领域，V4视区细胞的颜色恒定现象(Zeki 1983)也需要视觉空间的横向相互作用，比较来自视野不同部分表面的光的波长分布。这些研究中提出的影响，就像我们自己在定向领域的工作一样，是调节的。去除躯体感觉输入后皮质地形图的长期变化(Merzenich等人)。1984,1988)或视网膜损伤表明，通过适当的操作，侧向相互作用可以增强到激活突触后细胞的程度。虽然视网膜损伤明显代表感觉输入的异常中断，但它们仍可能代表在正常情况下发生的神经网络的长期重组，例如记忆所需的神经网络。
The findings presented in these studies have brought out different ideas concerning the mechanisms of processing in primary visual cortex than were held at the outset. Rather than thinking of receptive fields as being restricted in their extent, with the process of integration of the components of an image occurring at a much later stage along the visual pathway, we have shown that the integrative process is a progressive one, beginning in the primary visual cortex (or perhaps even earlier) and building up in a cascading series of converging and diverging connections. Rather than thinking of the filter characteristics of a cell as being fixed, it is apparent that they are dynamic and can be modified by the context in which features are presented. Finally, rather than a cortex with a functional architecture that is fixed after a critical period ending in infancy, we find that perturbing the system can lead to long-term topographical reorganization. Other examples of contextual interactions have been demonstrated in the submodalities of motion, where a cell's directional selectivity is modulated by the presence of movement in the surround (Allman et al. 1985; Tanaka et al. 1986; Gulyas et al. 1987; Orban et al. 1987). In the domain of color, the phenomenon of color constancy, reported for cells in visual area V4 (Zeki 1983), also requires lateral interactions in visual space, comparing the wavelength distribution of light coming from surfaces in different parts of the visual field. The influences presented in these studies, as in our own work in the domain of orientation, are modulatory. The long-term changes in cortical topography following removal of somatosensory input (Merzenich et al. 1984, 1988) or by retinal lesions suggest that with the appropriate manipulations the lateral interactions can be enhanced to the point of activating the postsynaptic cells. Although retinal lesions clearly represent an abnormal disruption of sensory input, they may nevertheless be representative of long-term reorganizations of neural networks occurring under normal circumstances, such as those required for memory.