Dynamics of neuronal sensitivity in visual cortex and local feature discrimination
Dynamics of neuronal sensitivity in visual cortex and local feature discrimination
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DOI：
10.1038/nn900
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发表时间：
2002-09-01
影响因子：
25
通讯作者：
Sur, M
中科院分区：
文献类型：
--
作者：
Dragoi, V;Sharma, J;Sur, M
自然场景的一个引人注目的方面是，图像特征（如线方向）在相邻的空间位置上具有很强的相关性，但在遥远的位置上则不相关。因此，在观看场景期间，眼睛运动通常伴随着图像的取向结构的变化。这种行为如何影响视觉皮层神经元对局部特征的辨别和编码？在这里，我们研究了短暂暴露于定向图像模式在猴子和人类引起的感知变化的方向，然后使用反向相关来研究神经元的敏感性在初级视觉皮层（V1）的行为猴子的动态变化。而短暂的适应定向光栅削弱识别附近的方向，通过扩大方向选择性和改变个别V1神经元的首选方向，它实际上增强了识别正交方向锐化神经元的选择性。因此，连续暴露于不同空间结构的图像块增强了区分局部特征的能力和V1神经元对这些特征的编码。
A striking aspect of natural scenes is that image features such as line orientation are strongly correlated at neighboring spatial locations but not at distant locations. Thus, during the viewing of a scene, eye movements are often accompanied by a change in the orientation structure of the image. How does this behavior influence the discrimination of local features and their encoding by visual cortical neurons? Here we examined the perceived changes in orientation induced by brief exposure to oriented image patterns in monkeys and humans, and then used reverse correlation to investigate dynamic changes in neuronal sensitivity in the primary visual cortex (V1) of behaving monkeys. Whereas brief adaptation to an oriented grating impaired identification of nearby orientations by broadening orientation selectivity and changing the preferred orientation of individual V1 neurons, it actually enhanced the identification of orthogonal orientations by sharpening neuronal selectivity. Hence, successive exposure to image patches of dissimilar spatial structure enhances both the ability to discriminate local features and the encoding of these features by V1 neurons.