Visual Areas in Posterior Parietal Cortex

本研究的目的是研究新大陆猕猴顶叶后皮质第5区的组织结构。在历史上，第5区主要被认为是一个体感区域，但最近的数据证实，它是一个双峰视觉和体感区域，具有用前肢进行视觉引导到达的特殊功能。邻近后顶叶 已经用单单位和多单位记录技术探索了7a、LTP和VIP等视觉区域，但还没有开发出区域5的总范围和内部组织，并且对其与上述到达行为的联系知之甚少。Titi猕猴皮质区域的组织结构与猕猴相似，但由于顶后区域的脑沟数量相对较少，因此更容易接近。在本研究中，多单元 电生理记录将被用来指导将神经解剖学示踪剂放置到Titi猴子的5区，以检查5区与大脑其他视觉和运动区的解剖联系。多单位电生理学还将用于检查5区内的视觉和躯体感觉反应。组织化学方法还将用于确定5区的内部解剖组织，并将与连接和生理数据进行比较。这种多单位电生理学与连接和组织化学方法在同一动物中的结合是一种新颖而有效的方法。

The goal of this study is to examine the organization of area 5 of in the posterior parietal cortex of New World titi monkeys. Historically, area 5 has been largely regarded as a somatosensory area, but recent data confirms that it is a bimodal visual and somatosensory area, with specialized functions for visually guided reaching with the forelimb. Nearby posterior parietal visual areas such as 7a, LtP and VIP have been explored with single and multiunit recording techniques, but the total extent and internal organization of area 5 has not been developed, and little is known about its connections pertaining to the reaching behavior described above. The titi monkey cortical fields are organized similarly to the macaque, but are more easily accessible due to the relatively fewer number of sulci in the posterior parietal region. In this study, multiunit electrophysiological recordings will be used to guide the placement of neuroanatomical tracers into area 5 of the titi monkey to examine the anatomical connections of area 5 with other visual and motor areas of the brain. Multiunit electrophysiology will also be used to examine the visual and somatosensory responses within area 5. Histochemical methods will also be used to determine the internal anatomical organization of area 5, and will be compared with the connectional and physiological data. This combination of multiunit electrophysiology with connectional and histochemical methods in the same animals is a novel and powerful approach.