Xiao D K, Raiguel S, Marcar V, Koenderink J, Orban G A
Laboratorium voor Neuro- en Psychofysiologie, Katholieke Universiteit Leuven, School of Medicine, Belgium.
Proc Natl Acad Sci U S A. 1995 Nov 21;92(24):11303-6. doi: 10.1073/pnas.92.24.11303.
A recurrent theme in the organization of vertebrate visual cortex is that of receptive fields with an associated "silent" opponency component. In the middle temporal area (area MT), a cortical visual area involved in the analysis of retinal motion in primates, this opponency appears in the form of a region outside the classical receptive field (CRF) that in itself gives no response but suppresses responses to motion evoked within the CRF. This antagonistic motion surround has been described as very large and symmetrically arrayed around the CRF. On the basis of this view, the primary function of the surround has long been thought to consist of simple figure-ground segregation based on movement. We have made use of small stimulus patches to map the form and extent of the surround and find evidence that the surround inhibition of many MT cells is in fact confined to restricted regions on one side or on opposite sides of the CRF. Such regions endow MT cells with the ability to make local-to-local motion comparisons, capable of extracting more complex features from the visual environment, and as such, may be better viewed as intrinsic parts of the receptive field, rather than as separate entities responsible for local-to-global comparisons.
脊椎动物视觉皮层组织中一个反复出现的主题是具有相关“沉默”拮抗成分的感受野。在颞中区（MT区），这是一个参与灵长类动物视网膜运动分析的皮层视觉区域，这种拮抗以经典感受野（CRF）之外的一个区域的形式出现，该区域本身不产生反应，但会抑制CRF内诱发的运动反应。这种拮抗性运动周边被描述为非常大且围绕CRF对称排列。基于这种观点，长期以来人们一直认为周边的主要功能是基于运动进行简单的图形-背景分离。我们利用小刺激斑块来绘制周边的形式和范围，并发现证据表明，许多MT细胞的周边抑制实际上局限于CRF一侧或两侧的受限区域。这些区域赋予MT细胞进行局部到局部运动比较的能力，能够从视觉环境中提取更复杂的特征，因此，它们可能更好地被视为感受野的固有部分，而不是负责局部到全局比较的单独实体。
