ANATOMY OF THE PRIMATE VISUAL SYSTEM

为了更好地理解视觉关联皮层在 感知和记忆，我们一直在研究功能 猕猴大脑皮层的组成部分， 通过使用神经解剖追踪它们的相互联系 技术结合电生理记录， 神经活动 我们的研究结果表明， 独立的视觉区域位于初级视觉皮层之外，或者 纹状皮层（VI），在信息处理流。 这些区域被组织成两个不同的皮质 每个通路具有V1作为其初始输入的源。 一、 一个枕颞通路，使视觉识别， 对象，而另一个，枕顶通路，介导 对物体之间空间关系的理解， 以及对物体运动的视觉引导， 空间 沿着枕颞通路的视觉区（V1， V2、V3、V4和下颞叶的TEO和TE区 皮质）似乎主要是作为一个系列层次结构， 每个区域处理颜色和形状信息。 通过 相反，沿枕顶径路的沿着区域（V1，MT， 和MT在顶叶皮层的投射区）处理 刺激运动的方向。 因为这其中的一个主要组成部分 通路在上级颞沟内向前延伸， 视觉空间功能的神经机制可能是 比以前想象的更广泛。 建立联系 枕颞和枕顶两条通路， 运动系统，我们一直在探索 视觉关联皮层到纹状体。 到目前为止，我们发现 TE、TEO和V4都投射到尾状核的尾部 核和腹侧壳核，这种排列与 从枕颞径路投射到 边缘系统，它只产生于TE。 的存在 直接投射到纹状体，而不是边缘系统 V4和TEO可能解释了TE猴的能力 损害获得视觉习惯，但不是视觉记忆。

To better understand the role of visual association cortex in perception and memory, we have been examining the functional areas that comprise this cortex in the macaque and exploring their interconnections by the use of neuroanatomical tracing techniques in combination with electrophysiological recording of neural activity. Our results indicate that a multiplicity of separate visual areas lie beyond the primary visual cortex, or striate cortex (Vl), in the stream of information processing. These areas are organized into two divergent corticocortical pathways, each having Vl as the source of its initial input. One, an occipitotemporal pathway, enables the visual recognition of objects, while the other, an occipitoparietal pathway, mediates the appreciation of the spatial relationships among objects as well as the visual guidance of movements toward objects in space. The visual areas along the occipitotemporal pathway (Vl, V2, V3, V4, and areas TEO and TE of the inferior temporal cortex) appear to be organized primarily as a serial hierarchy, in which each area processes both color and form information. By contrast, the areas along the occipitoparietal pathway (Vl, MT, and MT's projection zones in parietal cortex) process the direction of stimulus motion. Because a major component of this pathway extends anteriorly within the superior temporal sulcus, the neural mechanisms underlying visuospatial function may be more extensive than previously thought. To establish the links of both the occipitotemporal and occipitoparietal pathways with the motor system, we have been exploring the projections of visual association cortex to the striatum. So far, we have found that TE, TEO and V4 all project to the tail of the caudate nucleus and ventral putamen, an arrangement that contrasts with the pattern of projections from the occipitotemporal pathway to the limbic system, which arise from TE only. The presence of direct projections to the striatum but not to the limbic system from V4 and TEO may explain the ability of monkeys with TE lesions to acquire visual habits but not visual memories.