Sillito A M, Jones H E
Department of Visual Science, University College London, UK.
J Physiol Paris. 1996;90(3-4):205-9. doi: 10.1016/s0928-4257(97)81424-6.
We examined the influence of stimulus context on the response of cells in primate V1 utilising both concentric and spatially discrete stimuli. The majority of cells (63/71) showed marked patch suppression, including non-oriented cells. This suppression was reduced or lost if there was an orientation discontinuity in the stimulus overlying the receptive field. Cross-oriented stimuli could exert strong facilitatory effects so that a cell's response to an optimally oriented stimulus over its receptive field was increased by the presence of an adjacent cross-oriented stimulus. This increase appeared to involve both disinhibition as well as a direct facilitation. The strength of the cross-orientation effects was such that for some cells it seemed appropriate to define a cross-oriented stimulus configuration as the 'optimal' stimulus. Effects following from orientation context could be strongly influenced by stimulus direction. Subcortical as well as cortical interactions may contribute to these observations. It is suggested that the properties of the network as a whole define the responses of individual cells and that the representation of discontinuities is an important component of network function in V1.
我们利用同心和空间离散刺激，研究了刺激背景对灵长类动物初级视皮层（V1）细胞反应的影响。大多数细胞（63/71）表现出明显的斑块抑制，包括非定向细胞。如果覆盖感受野的刺激中存在方向不连续性，这种抑制会减弱或消失。交叉定向刺激可产生强烈的易化作用，因此，相邻交叉定向刺激的存在会增强细胞对其感受野上最佳定向刺激的反应。这种增强似乎涉及去抑制以及直接易化。交叉定向效应的强度使得对于某些细胞而言，将交叉定向刺激配置定义为“最佳”刺激似乎是合适的。方向背景产生的效应可能会受到刺激方向的强烈影响。皮层下以及皮层间的相互作用可能有助于这些观察结果。有人提出，整个网络的特性决定了单个细胞的反应，并且不连续性的表征是V1中网络功能的重要组成部分。
