Vestibular influences on the macaque navigation circuit

 描述(申请人提供)：以前对啮齿类动物的研究已经确定了四种主要的细胞类型，包括头部方向(HD)、位置、网格和边界细胞。据报道，在啮齿动物中，HD细胞编码头部指向的方向，与动物的行为或空间位置无关，并已在丘脑前部、海马体、下丘脑和其他海马旁区域被发现。虽然已经从啮齿动物模型中了解到了许多关于HD细胞反应的知识，但它也有局限性。例如，很难确定HD细胞编码的是头部方向还是凝视方向。在……里面 此外，尽管病变研究表明HD细胞的调谐取决于前庭提示，但这些信号的类型和性质仍然不清楚。我们建议检查恒河猴的HD细胞反应，在那里这些问题的答案很容易确定。我们的第一个目标是定位、描述和比较恒河猴丘脑前部和下丘脑复合体中HD细胞的调谐特性。我们的第二个目标是确定这两个区域的HD细胞是否编码头部方向或凝视方向。我们将训练猕猴分离眼睛和头部的位置，并使用Fisher信息分析来确定HD细胞与头部方向或凝视方向调整是否更密切相关。我们假设大多数猕猴HD细胞编码头部方向，尽管有些细胞可能被调节到凝视方向，并且每种细胞类型的相对比例在丘脑前部和下丘脑之间可能不同。我们的第三个目标是描述HD细胞在光和黑暗中被动旋转时的三维、重力相关的特性。该项目代表了一个新的研究领域，通过合作努力，长期目标是了解灵长类空间导航的潜在机制。

 DESCRIPTION (provided by applicant): Previous studies in rodents have identified four major cell types that are involved in navigation functions, including head direction (HD), place, grid, and border cells. In rodents, HD cells are reported to encode the direction the head is pointing independent of the animal's behavior or spatial location and have been identified in the anterior thalamus, hippocampus, subiculum, and other parahippocampal regions. Although much has been learned regarding HD cell responses from the rodent model, it has limitations. For example, it has been difficult to determine if HD cells encode head direction or gaze direction. In addition, although lesion studies have shown that HD cell tuning is dependent upon vestibular cues, the type and properties of these signals remain obscure. We propose to examine HD cell responses in rhesus macaques, where answers to these questions can readily be determined. Our first goal will be to localize, characterize, and compare the tuning properties of macaque HD cells in the anterior thalamus and subiculum complex. Our second goal is to determine if HD cells in these two regions encode head direction or gaze direction. We will train macaques to dissociate eye and head position and use Fisher information analysis to determine whether HD cells are more closely related to head direction or gaze direction tuning. We hypothesize that most macaque HD cells encode head direction, although some might be tuned to gaze direction and the relative proportion of each cell type might differ between the anterior thalamus and subiculum. Our third goal is to characterize the three- dimensional, gravity-dependent properties of HD cells during passive rotations in both the light and darkness. The project represents a new area of research through a collaborative effort, with the long-term goal to understand the mechanisms underlying primate spatial navigation.