Excitatory-inhibitory network in the visual cortex: Psychophysical evidence
Excitatory-inhibitory network in the visual cortex: Psychophysical evidence
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DOI：
10.1073/pnas.94.19.10426
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发表时间：
1997-09-16
影响因子：
11.1
通讯作者：
Tsodyks, M
中科院分区：
文献类型：
--
作者：
Adini, Y;Sagi, D;Tsodyks, M
在视觉加工的早期阶段，细胞对具有特定特征的局部刺激做出反应，如方位和空间频率，尽管这些细胞的感受野被认为是局部的和独立的，但最近的生理和心理物理证据表明，细胞参与了一个丰富的局部连接网络，因此，这些局部处理单元可以整合视野中更大部分的信息；他们对刺激的反应模式明显依赖于所呈现的语境，为了探索不同语境条件下人类视觉皮质的横向相互作用模式，我们使用了一种新的链式横向掩蔽检测范式，在该范式中，人类观察者在不同长度的高对比度Gabor信号链存在的情况下执行检测任务，结果表明检测阈值与侧翼数量之间存在非单调关系。远程侧翼填充其他侧翼对目标检测有较强的影响，表明探测阈值是由大脑皮层中大量神经元群体的动态变化引起的，兴奋和抑制之间存在主要的相互作用。我们认为初级视皮层的模型是一个由兴奋和抑制细胞群体组成的网络，既有短距离的相互作用，也有远程的相互作用，在一系列参数范围内，该模型表现出与实验结果相似的行为，实验和建模结果表明，远程连接在视觉知觉中起着重要的作用，可能中介了语境的影响。
At early stages in visual processing cells respond to local stimuli with specific features such as orientation and spatial frequency, Although the receptive fields of these cells have been thought to be local and independent, recent physiological and psychophysical evidence has accumulated, indicating that the cells participate in a rich network of local connections, Thus, these local processing units can integrate information over much larger parts of the visual field; the pattern of their response to a stimulus apparently depends on the context presented, To explore the pattern of lateral interactions in human visual cortex under different context conditions we used a novel chain lateral masking detection paradigm, in which human observers performed a detection task in the presence of different length chains of high-contrast-flanked Gabor signals, The results indicated a nonmonotonic relation of the detection threshold with the number of flankers. Remote flankers had a stronger effect on target detection when the space between them was filled with other flankers, indicating that the detection threshold is caused by dynamics of large neuronal populations in the neocortex, with a major interplay between excitation and inhibition, We considered a model of the primary visual cortex as a network consisting of excitatory and inhibitory cell populations, with both short-and long-range interactions, The model exhibited a behavior similar to the experimental results throughout a range of parameters, Experimental and modeling results indicated that long-range connections play an important role in visual perception, possibly mediating the effects of context.