A ROLE FOR THE CORPUS-CALLOSUM IN VISUAL AREA V4 OF THE MACAQUE
A ROLE FOR THE CORPUS-CALLOSUM IN VISUAL AREA V4 OF THE MACAQUE
复制标题
DOI：
10.1017/s095252380000328x
复制
发表时间：
1993-01-01
影响因子：
1.9
通讯作者：
MISHKIN, M
中科院分区：
文献类型：
--
作者：
DESIMONE, R;MORAN, J;MISHKIN, M
经典定义的V4细胞的感受野几乎完全局限于对侧视野。然而，这些感受野通常被大的、沉默的抑制区域包围，并且刺激周围区域可以导致对感受野内同时呈现的刺激的反应的完全抑制。我们研究了抑制性环绕物是否可能跨越中线延伸到同侧视野，如果是这样，环绕物是否依赖于胼胝体，胼胝体在V4中具有广泛的分布。我们发现，在V4的中央视野表示中测试的一半以上的细胞的周围交叉进入同侧视野，其中一些延伸到至少16度的垂直子午线。这种来自同侧场的抑制大部分是由胼胝体介导的，因为胼胝体的部分显著地降低了周围的强度和范围。然而，仍然存在一些残余抑制，并没有通过增加前连合病变进一步减少。因为残余的同侧抑制的大小和程度与V4记录对侧视束切片后发现的相似，我们得出结论，它是视网膜起源的。使用相同的技术在V4中，我们还映射了同侧范围的周围在中央凹表示的V1在一个完整的猴子。结果与连合或对侧束切片后V4中的结果非常相似。研究结果表明，V4是一个中心网站的长距离相互作用内和跨两个视觉半野。与以前的工作，结果是一致的概念，即大的抑制周围的V4神经元有助于颜色恒常性和图形-背景分离的神经机制。
The classically defined receptive fields of V4 cells are confined almost entirely to the contralateral visual field. However, these receptive fields are often surrounded by large, silent suppressive regions, and stimulating the surrounds can cause a complete suppression of response to a simultaneously presented stimulus within the receptive field. We investigated whether the suppressive surrounds might extend across the midline into the ipsilateral visual field and, if so, whether the surrounds were dependent on the corpus callosum, which has a widespread distribution in V4. We found that the surrounds of more than half of the cells tested in the central visual field representation of V4 crossed into the ipsilateral visual field, with some extending up to at least 16 deg from the vertical meridian. Much of this suppression from the ipsilateral field was mediated by the corpus callosum, as section of the callosum dramatically reduced both the strength and extent of the surrounds. There remained, however, some residual suppression that was not further reduced by addition of an anterior commissure lesion. Because the residual ipsilateral suppression was similar in magnitude and extent to that found following section of the optic tract contralateral to the V4 recording, we concluded that it was retinal in origin. Using the same techniques employed in V4, we also mapped the ipsilateral extent of surrounds in the foveal representation of V1 in an intact monkey. Results were very similar to those in V4 following commissural or contralateral tract sections. The findings suggest that V4 is a central site for long-range interactions both within and across the two visual hemifields. Taken with previous work, the results are consistent with the notion that the large suppressive surrounds of V4 neurons contribute to the neural mechanisms of color constancy and figure-ground separation.