HIPPOCAMPAL SPATIAL REPRESENTATIONS

海马空间表示

• 批准号: 3121132
• 负责人: SHERI J. Y. MIZUMORI
• 金额: $ 7.05万
• 依托单位: UNIVERSITY OF UTAH
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-05-01 至 1994-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3121132
• 关键词: age difference; aging; animal old age; behavior test; brain electrical activity; brain mapping; carbachol; central neural pathway /tract; cognition; experimental brain lesion; glutamates; hippocampus; laboratory rat; local anesthetics; microinjections; muscimol; neural information processing; neurophysiology; space perception

Spatial abilities are often observed to decline as a result of normal aging in both humans and rats. In the interest of the future development of appropriate therapeutic treatments, it is necessary to understand the contribution of age-related changes in brain organization. The hippocampus is a particularly interesting structure for study in this regard because it is considered critical for the acquisition of new spatial information, and it appears particularly susceptible to age-associated pathological abnormalities. Thus, the prim,dry focus of this research is to understand the relationship between physiological properties of a senescent hippocampal formation and spatial performance in rats. Since synaptic activation within hippocampus is extensively modulated by different subcortical afferents (some of which are known to undergo significant changes with age), this research will also examine the possibility that age-related changes in subcortical inputs influence the accuracy with which the hippocampus represents spatial aspects if an environment. The specific goals of this proposal is to provide a comprehensive evaluation of the contributions of neural representations of space and movement in the hippocampus to impaired spatial performance by aged rats. This goal will be accomplished in two parts: First discharge of different populations of single hippocampal neurons will be correlated with specific behaviors and spatial cognitive skills of young and old animals. Also, possible age differences in factors such as attention to spatial cues will be considered in terms of age-related changes in choice accuracy and neurophysiological function. Part 2 of this proposal will assess the effects of age on subcortical modulation of hippocampal function by monitoring behavioral and physiological consequences of selective and reversible deafferentation in young and old rats performing a spatial memory task. Seven afferent structures will be examined. Temporary deafferentation will be achieved by microinjection of a local anesthetic (tetracaine) or a GABA agonist (muscimol) into afferent nuclei. Using an injection-recording procedure that was recently developed for this research, the immediate behavioral and physiological consequences of selective deafferentation, as well as recovery back to baseline conditions. will be observed. Afferent activation effects will be tested by local injection of glutamate or carbachol. In summary, these results should provide important insight into possible age-changes in the neural representation of information critical for accurate spatial behaviors.

空间能力通常会因正常衰老而下降 在人类和老鼠中。 为了今后的发展 适当的治疗方法，有必要了解 与年龄相关的大脑组织变化的贡献。 海马体 在这方面是一个特别有趣的研究结构，因为它 被认为对于获取新的空间信息至关重要，并且 它似乎特别容易受到与年龄相关的病理影响 异常。 因此，这项研究的首要重点是了解 衰老生理特性之间的关系 大鼠海马的形成和空间表现。 由于突触 海马体内的激活受到不同因素的广泛调节 皮质下传入神经（其中一些已知会经历显着的 随着年龄的变化），这项研究还将检验以下可能性： 皮层下输入与年龄相关的变化会影响预测的准确性 海马体代表环境的空间方面。 该提案的具体目标是提供全面的 评估空间神经表征的贡献 海马体的运动会损害老年大鼠的空间表现。 这一目标将分两部分完成：首先排放不同的 单个海马神经元的数量将与特定的 年轻和年老动物的行为和空间认知技能。 还， 对空间线索的关注等因素可能存在年龄差异 考虑与年龄相关的选择准确性变化和 神经生理功能。 该提案的第 2 部分将评估 年龄对皮层下海马功能调节的影响 监测选择性和生理后果 年轻和年老大鼠的可逆性传入神经阻滞 记忆任务。 将检查七个传入结构。 暂时的 通过显微注射局部麻醉剂来实现传入阻滞 （丁卡因）或 GABA 激动剂（蝇蕈醇）进入传入核。 使用 最近为此开发的注射记录程序 研究，直接的行为和生理后果 选择性传入神经阻滞，以及恢复到基线条件。 将被观察。 传入激活效果将通过局部测试 注射谷氨酸或卡巴胆碱。 总而言之，这些结果应该 为了解神经系统中可能的年龄变化提供重要的见解 对准确空间行为至关重要的信息表示。