FMRI INVESTIGATIONS OF PFC-MTL INTERACTIONS IN HUMANS

项目总结(见说明)： 项目2将功能磁共振成像(FMRI)与功能和有效的连接方法相结合，以检查在需要上下文相关学习和提取的任务中，人类前额叶(PFC)和内侧颞叶(MTL)区域之间的相互作用。我们将在与任务密切相关的基于上下文的联想和基于上下文的推理任务中使用fMRI范式 用于选择性PFC或MTL病变的患者(项目1)、猴子(项目3)和啮齿动物(项目4和5)。由于人类和非人类灵长类神经解剖学之间的同源性为我们提出的人类实验提供了一个框架，我们将人类神经成像任务与项目3中的任务紧密匹配。第一个目标是使用功能磁共振结合功能和有效的连接性分析方法来检查基于上下文的联想记忆任务的学习和提取阶段MTL和PFC区域之间相互作用的差异。第二个目标将检查基于上下文的推理任务中MTL和PFC区域之间的相互作用。第三个目标将是 使用关系加载任务检查MTL和PFC交互。我们将检查血液氧合水平(BOLD)活动的模式，以及与试验中不同行为时期(样本、延迟、选择)相关的功能和有效连接。除了使用标准的单变量fMRI方法进行数据分析外，还将使用附加的功能和有效的连通性方法来 研究PFC和MTL区域之间的功能相互作用。通过比较啮齿动物、猴子和人类在相关任务中的结果，这些实验使我们能够检查PFC-MTL相互作用和跨物种的功能同源性。实验结果将指导计算技术的发展。 整合这些跨物种调查结果的模型(项目6)，以及有效的连通性分析和建模将与分析核心一起进行。

PROJECT SUMMARY (See instructions): Project 2 will combine functional magnetic resonance imaging (fMRI) with functional and effective connectivity methods to examine the interactions between regions of the prefrontal cortex (PFC) and medial temporal lobe (MTL) in humans during tasks requiring context-dependent learning and retrieval. We will use fMRI paradigms in context-based associative and context-based inference tasks closely related to tasks used in patients with selective PFC or MTL lesions (Project 1), in monkeys (Project 3), and in rodents (Projects 4 and 5). Since the homology between the human and non-human primate neuroanatomy provides a framework for our proposed human experiments, we have closely matched the human neuroimaging tasks to the tasks in Project 3. The first aim is to use fMRI in combination with functional and effective connectivity analysis methods to examine differences in interactions between the MTL and PFC regions during the learning and retrieval phases of a context-based associative memory task. The second aim will examine interactions between the MTL and PFC regions during a context-based inference task. The third aim will examine MTL and PFC interactions using a relational-load task. We will examine patterns of blood oxygenation level (BOLD) activity and functional and effective connectivity associated with different behavioral periods within trials (sample, delay, choice). In addition to using standard univariate fMRI methods for data analysis, addifional functional and effective connectivity methods will be employed to examine functional interactions between PFC and MTL regions. By comparing results in related tasks across rodents, monkeys, and humans, these experiments allow us to examine PFC-MTL interactions and functional homologies across species. The experimental results will guide the development of computational models that integrate these findings across species (Project 6), and the effective connectivity analysis and modeling will be done in conjunction with the Analysis Core.