Visual Areas in Posterior Parietal Cortex

本研究的目的是研究新大陆猕猴后顶叶皮层第5区的组织结构。从历史上看，5区在很大程度上被认为是一个躯体感觉区，但最近的数据证实，它是一个双峰视觉和躯体感觉区，具有视觉引导前肢到达的专门功能。靠近后顶骨 视觉区域如7a、LtP和VIP已经用单个和多单元记录技术进行了探索，但是区域5的总范围和内部组织还没有开发，并且关于其与上述到达行为有关的连接知之甚少。提提猴皮质区的组织结构与猕猴相似，但由于后顶叶区域的脑沟数量相对较少，因此更容易接近。在这项研究中， 电生理学记录将用于指导将神经解剖学示踪剂放置到Titi猴的5区中，以检查5区与大脑的其他视觉和运动区的解剖学连接。多单位电生理学也将用于检查5区内的视觉和体感反应。组织化学方法也将用于确定5区的内部解剖组织，并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组合是一种新颖而强大的方法。

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.