CAUDATE AND HIPPOCAMPAL CONTRIBUTION TO SPATIAL LEARNING

描述(改编自申请人的摘要)：相对较新 基底节患者行为缺陷的再评估 功能障碍已显示出显著的认知障碍。 这些结果特别令人惊讶，因为在一段时间里，基本的 神经节被认为是运动控制系统的延伸。 以试图确定基本的认知结果 神经节(尤其是纹状体)受损，动物研究人员关注 基底节在大鼠学习记忆中的作用 猴子。啮齿动物损伤文献表明， 尾状刺激反应或以自我为中心的学习形式(分离它 来自啮齿动物海马体进行的基于情境的学习)，而 灵长类电生理证据支持尾状核在脑内的双重作用 既有刺激反应学习，也有上下文依赖学习。在这里，我们展示了一种 响应学习之间的明显差异的潜在解决方案 以及对尾状核的语境解释。我们建议， 尾部提供了一个响应参考系统来帮助定义 被认为适合当前上下文的未来操作 不管要学习的具体任务是不是刺激反应 本质上或涉及更灵活的上下文相关处理 学习。在空间学习中，我们认为，虽然海马区的感觉 语境系统对动物组织感官很重要 不同方式的信息，尾状响应参照系统允许 动物快速重新定义响应选项以满足环境需求 变化，后者可以在许多类型的 行为。区分严格反应理论和反应 尾状核参考理论，尾状核单个的行为相关 以老鼠为特征的单位活动执行空间上下文任务， 自我中心反应任务，或径向迷宫上的随机强迫选择任务 或者是T形迷宫。将记录海马区细胞活动 与尾状核活动同时进行，以便直接分析 这两种结构对不同形式的学习的相对贡献。 多巴胺调节学习诱导单位改变的可能性 尾状核将通过观察多巴胺神经毒素的影响进行测试 单位行为相关。这样，我们不仅解决了什么是独一无二的 尾状核在不同的学习形式中有不同的作用，也有怎样的尾状核 可能有助于形成更大的神经回路，使有机体 最终在感官解释方面具有最大的灵活性 响应选项。

DESCRIPTION (Adapted from applicant's abstract): Relatively recent re-evaluations of the behavioral deficits of patients with basal ganglia dysfunction have revealed significant and striking cognitive impairments. These results were particularly surprising because for some time, the basal ganglia have been thought of as an extension of the motor control system. In an attempt to determine the precise cognitive consequence of basal ganglia (in particular striatum) compromise, animal researchers have focused on the contribution of the basal ganglia to learning and memory in rat and monkey. The rodent lesion literature suggests a selective role for the caudate stimulus-response or egocentric forms of learning (dissociating it from the context-based learning performed by rodent hippocampus), while the primate electrophysiological evidence supports a dual role for caudate in both stimulus-response and context-dependent learning. Here we present a potential resolution to the apparent discrepancy between response learning and contextual interpretations of the caudate nucleus. We propose that the caudate provides a response reference system to help define the goals of future actions that are deemed appropriate for the current context regardless of whether the specific task to be learned is stimulus-response in nature or involves the more flexible processing of context-dependent learning. In spatial learning, we argue that while the hippocampal sensory context system is important to allow the animal to organize sensory information in different ways, the caudate response referent system allows animals to quickly redefine response options as environmental demands change, the latter of which can play fundamental roles in many types of behavior. To distinguish between a strictly response theory and a response reference theory of caudate, the behavioral correlates of caudate single unit activity characterized as rats perform either a spatial context task, an egocentric response task, or a random forced choice task on a radial maze or a T-maze. Hippocampal place cell activity will be recorded simultaneously with the caudate activity to allow for direct analysis of the relative contributions of the two structures to different forms of learning. The possibility that dopamine regulates the learning-induced unit changes in caudate will be tested by looking at the effects of a dopamine neurotoxin unit-behavioral correlates. In this way, we not only address what unique role caudate has in different forms of learning, but also how the caudate may contribute to a larger neural circuit that allows organisms to ultimately have maximal flexibility in terms of sensory interpretations and response options.