Pattern adaptation and cross-orientation interactions in the primary visual cortex
Pattern adaptation and cross-orientation interactions in the primary visual cortex
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DOI：
10.1016/s0028-3908(98)00069-0
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发表时间：
1998-04-01
影响因子：
4.7
通讯作者：
Ferster, D
中科院分区：
文献类型：
--
作者：
Carandini, M;Movshon, JA;Ferster, D
初级视觉皮层（V1）神经元的反应性在有效模式的视觉刺激几秒钟后大幅降低。这种现象被称为模式适应，是大脑皮层特有的，可能是各种感知后效应的基础。虽然适应一个给定的模式减少了V1神经元的反应，所有随后看到的测试模式，这种减少显示了一些特异性，最强的适应和测试模式是相同的。这种特异性可能表明适应影响了由适应刺激共同激活的神经元组之间的相互作用。我们研究了这种可能性，通过研究适应视觉模式的影响，包含一个或两个方向的首选方向为一个细胞，和方向正交，因为在初级视觉皮层的神经元的方向是尖锐的调整，刺激与正交方向兴奋两个很大程度上不同的神经元群体。与猫V1神经元的膜电位的细胞内记录，我们发现，适应的正交方向单独不引起超极化，这是典型的适应的首选方向。与细胞外记录的猕猴V1神经元的放电率，我们发现，响应不减少适应的正交方向单独几乎一样多的适应的首选方向。在猕猴，我们还研究了适应的效果，以格子包含首选和正交方向。我们发现，适应这些刺激可以修改方向之间的相互作用。它增加了一些细胞显示的交叉取向抑制的量，甚至将一些在适应空白刺激时显示交叉取向易化的细胞转变为显示交叉取向抑制的细胞。这一结果表明，模式适应可以影响相互作用的神经元组之间的正交方向调整，无论是通过增加他们的相互抑制或减少他们的相互兴奋。(C)1998爱思唯尔科技有限公司版权所有。
The responsiveness of neurons in the primary visual cortex (V1) is substantially reduced after a few seconds of visual stimulation with an effective pattern. This phenomenon, called pattern adaptation, is uniquely cortical and is the likely substrate of a variety of perceptual after-effects. While adaptation to a given pattern reduces the responses of V1 neurons to all subsequently viewed test patterns, this reduction shows some specificity, being strongest when the adapting and test patterns are identical. This specificity may indicate that adaptation affects the interaction between groups of neurons that are jointly activated by the adapting stimulus. We investigated this possibility by studying the effects of adaptation to visual patterns containing one or both of two orientations-the preferred orientation for a cell, and the orientation orthogonal to it. Because neurons in the primary visual cortex are sharply tuned for orientation, stimulation with orthogonal orientations excites two largely distinct populations of neurons. With intracellular recordings of the membrane potential of cat V1 neurons, we found that adaptation to the orthogonal orientation alone does not evoke the hyperpolarization that is typical of adaptation to the preferred orientation. With extracellular recordings of the firing rate of macaque V1 neurons, we found that the responses were not reduced by adaptation to the orthogonal orientation alone nearly as much as by adaptation to the preferred orientation. In the macaque we also studied the effects of adaptation to plaids containing both the preferred and the orthogonal orientations. We found that adaptation to these stimuli could modify the interactions between orientations. It increased the amount of cross-orientation suppression displayed by some cells, even turning some cells that showed cross-orientation facilitation when adapted to a blank stimulus into cells that show cross-orientation suppression. This result suggests that pattern adaptation can affect the inter-action between the groups of neurons tuned to the orthogonal orientations, either by increasing their mutual inhibition or by decreasing their mutual excitation. (C) 1998 Elsevier Science Ltd. All rights reserved.