Sun C, Chen X, Huang L, Shou T
Vision Research Laboratory and Liren Laboratory, Center for Brain Science Research, School of Life Sciences, Fudan University, Shanghai 200433, China.
Neuroscience. 2004;125(2):495-505. doi: 10.1016/j.neuroscience.2004.01.036.
The spatial properties of the extraclassical receptive fields (ECRF) of neurons responding to a stimulus restricted to it and its interaction with the classical receptive field (CRF) in visual information processing were investigated in 74 relay cells in the dorsal lateral geniculate nucleus (LGNd) of anesthetized cats. The results demonstrate that the ECRF of most relay cells in the LGNd responded preferentially to a grating stimulus of low spatial frequency through a mechanism of spatial summation. These biased cells showed a significant orientation bias which was relatively smaller than that of the CRF. The preferred orientations of the ECRF were not correlated with those of the CRF in most relay cells. The orientation biased ECRFs and CRFs interacted with each other in a non-linear way, resulting in a great diversity of response properties. Overall, the CRF played a more significant role than the ECRF in determining a cell's orientation bias and preferred orientation. The ECRF mostly showed a modulatory role mainly in suppressing and/or in partially facilitating the neural response to stimulation in the CRF although in some cases, the ECRF did determine a cell's responsiveness and orientation sensitivity. These results suggest that the ECRF might contribute to the ability of the LGNd neurons to detect some complex features such as texture segmentation and provide a subcortical contribution to the integrative field of visual cortical cells through receiving inputs from retinal ganglion cells with similar orientation biased extended surrounds [Neuroscience 98 (2000) 207].
在麻醉猫的背外侧膝状核（LGNd）中的74个中继细胞中，研究了对限于其自身的刺激作出反应的神经元的超经典感受野（ECRF）的空间特性，以及它在视觉信息处理中与经典感受野（CRF）的相互作用。结果表明，LGNd中大多数中继细胞的ECRF通过空间总和机制优先对低空间频率的光栅刺激作出反应。这些有偏向性的细胞表现出明显的方向偏向性，且相对小于CRF的方向偏向性。在大多数中继细胞中，ECRF的偏好方向与CRF的偏好方向不相关。具有方向偏向性的ECRF和CRF以非线性方式相互作用，导致反应特性的多样性。总体而言，在确定细胞的方向偏向性和偏好方向方面，CRF比ECRF发挥了更重要的作用。ECRF大多主要发挥调节作用，主要是抑制和/或部分促进对CRF中刺激的神经反应，尽管在某些情况下，ECRF确实决定了细胞的反应性和方向敏感性。这些结果表明，ECRF可能有助于LGNd神经元检测某些复杂特征（如纹理分割）的能力，并通过接收来自具有类似方向偏向性扩展周边的视网膜神经节细胞的输入，为视觉皮层细胞的整合场提供皮层下贡献[《神经科学》98（2000）207] 。
