Memory/Executive Systems in Prefrontal & Temporal Cortex

描述(申请人提供)：这项建议旨在评估前额叶皮质和两个内侧颞叶区域(海马结构和鼻皮质)在灵长类动物的从属记忆和执行功能中的存在和关系的性质。在恒河猴身上，我们将使用交叉损伤/分裂脑技术将内侧颞叶的这两个区域与前额叶皮质分离和断开，以评估这两个大脑区域在执行记忆和执行功能时是否存在功能交互作用。为了评估功能性相互作用的存在和性质，有必要首先评估双侧病变对这三个区域的具体影响。因此，在这项研究的第一阶段，将对双侧大脑背侧前额叶皮质(BFF)、海马体结构(BHH)或鼻皮质(BRR)受损的猴子进行认知测试。在该测试中，任务内和任务之间的执行功能和助记需求将发生系统的变化。在第二阶段(“断开”)，使用与第一阶段相同的测试电池，一个实验组(CfHS组)将接受单侧前额叶背侧皮质损伤和对侧海马结构损伤以及前脑连合的横断。这种损伤将使对侧大脑半球完整的海马体结构和前额叶皮质断开连接。第二个实验组(CFRS)将制备相同的单侧前额叶背侧皮质损伤，但对侧鼻孔皮质损伤并横断前脑连合。这一损伤将使完整的前额叶皮质与对侧大脑半球完整的海马旁皮质断开连接。为了评估这两种“断线”的效果，我们将把它们的表现与三个对照组进行比较。第一组为手术对照组(OC)，同时作为第一阶段双侧病变的对照。第二组(IFHS)将有单侧海马结构损害，同侧背外侧前额叶损害，以及前脑连合横断。这将产生与CfHS组相同的脑损伤，控制总的脑损伤，但将使同一侧的海马体结构和前额叶皮质完好无损并“相连”。第三组(IFRS)将有单侧鼻骨皮质损害，以及单侧前额叶背外侧皮质损害和前脑连合横断。这将产生与CFRS组相同程度的脑损伤，但一侧的鼻部和前额叶皮质完好无损，并被连接在一起。

DESCRIPTION (provided by applicant): This proposal is designed to assess the presence and nature of the relationship between the prefrontal cortex and two medial temporal lobe areas (hippocampal formation and rhinal cortices) in subserving memory and executive function in the primate. In the rhesus monkey, we will use a crossed lesion / split brain technique to isolate and disconnect these two regions of the medial temporal lobe from the prefrontal cortex in order to assess whether there exists a functional interaction between these two brain regions in the performance of memory and executive functions. In order to assess the presence and nature of a functional interaction, it will be necessary to first assess the specific effect of bilateral lesions on each of these three regions. Hence, in the first phase of the study, a cognitive test battery," in which executive function" and "mnemonic" demands within and across tasks will be systematically varied, will be administered to monkeys with bilateral lesions of either the dorsal prefrontal cortex (BFF), the hippocampal formation (BHH), or the rhinal cortices (BRR). In the second phase ("disconnections"), using the same test battery as in the first phase, one experimental group (Group CFHS) will receive a unilateral lesion of the dorsal prefrontal cortex and a contralateral lesion of the hippocampal formation together with a transection of the forebrain commissures. This lesion will disconnect the intact hippocampal formation and prefrontal cortex of the opposite hemispheres. The second experimental group (CFRS) will be prepared with the same unilateral lesion of the dorsal prefrontal cortex but a contralateral lesion of the rhinal cortices with transection of the forebrain commissures. This lesion will disconnect the intact prefrontal cortex from the intact parahippocampal cortices of the opposite hemispheres. In order to assess the effect of these two "disconnections", we will compare their performance to three control groups. The first will be an operated control group (OC) that will also serve as controls for the bilateral lesions in the first phase. The second group (IFHS) will have a unilateral hippocampal formation lesion, an ipsilateral dorsolateral prefrontal lesion, and a transection of the forebrain commissures. This will produce brain damage identical to that in group CFHS, controlling for the total brain damage, but will leave the hippocampal formation and prefrontal cortex on the same side intact and "connected". The third group (IFRS) will have a unilateral lesion of the rhinal cortices along with a unilateral lesion of the dorsolateral prefrontal cortex and transection of the forebrain commissures. This will produce the same degree of brain damage to that in group CFRS, but leave the rhinal and prefrontal cortices on one side intact and "connected".