Retrosplenial Cortex Interactions with Entorhinal Cortex and the Visual Anchoring of Spatial Representations

压后皮质与内嗅皮质的相互作用以及空间表征的视觉锚定

• 批准号: 9767295
• 负责人: Andrew S. Alexander
• 金额: $ 6.16万
• 依托单位: BOSTON UNIVERSITY (CHARLES RIVER CAMPUS)
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-30 至 2021-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9767295
• 关键词: Affect; Alzheimer' s Disease; Anatomy; Animals; Atrophic; Behavior; Behavioral Paradigm; Biological Assay; Cells; Cognition; Computer Simulation; Cues; Data; Data Analyses; Disease; Distal; Electrophysiology (science); Environment; Episodic memory; Exhibits; Fire - disasters; Functional disorder; Halorhodopsins; Hippocampus (Brain); Human; Impairment; Individual; Joints; Learning; Location; Maintenance; Maps; Medial; Memory; Methods; Modeling; Motor; Neurons; Opsin; Outcome; Pathology; Pattern; Periodicity; Positioning Attribute; Presynaptic Terminals; Rattus; Research; Rewards; Role; Rotation; Route; Sensory; Signal Transduction; Structure; System; Techniques; Testing; Time; Visual; Visual Cortex; Work; entorhinal cortex; experience; experimental study; in vivo; memory process; neurophysiology; novel; optogenetics; predictive modeling; presynaptic; response; theories; two-dimensional; visual information; visual processing; visual stimulus; way finding

The hippocampus (HPC), medial entorhinal cortex (MEC), and retrosplenial cortex (RSC) are strongly implicated in memory, and atrophy of all three structures serves as an early indicator of Alzheimer's disease. In parallel to memory processes, these structures are important for spatial cognition and neurons within these regions exhibit spatially-specific firing. HPC place cells fire when an animal occupies an explicit location in the environment relative to distal visual landmarks. MEC neurons encode multiple forms of spatial information, including grid fields, wherein a single neuron is active at multiple, equidistant locations that span the entire environment and form a periodic grid. Critically, dysfunction of MEC spatial patterning disrupts sequential encoding in the HPC which is thought to underlie episodic memory. Robust MEC spatially-related firing is known to require visual information which is likely routed to the region via RSC. RSC forms a strong excitatory projection into the region, and like MEC, firing of RSC neurons can be rhythmic and exhibit spatial periodicity. Further, individual RSC neurons encode sensory, motor, and spatial variables that are known to modulate MEC activation. Although it is known that RSC is part of the visual processing network, little is known as to how RSC spatial representations are influenced by the arrangement of distal visual cues or how visually-related RSC activation in turn influences MEC activation. Given the functional and anatomical relationship between RSC and MEC, it is pertinent to explore their connectivity and joint neurophysiological dynamics at this time. This proposal seeks to further our understanding of systems interactions between MEC and RSC in spatial encoding. The proposed experiments will assay the influence of visual information in RSC and MEC spatial representations through the implementation of visual cue manipulations that expand or compress the relative angle between visual landmarks while rats perform a visually-guided navigation paradigm. Additionally, the proposed experiments will utilize optogenetics to specifically inhibit RSC projections into MEC to test hypotheses that RSC input is required for MEC visual sensitivity. Data collected in these experiments will be utilized to test computational modeling predictions about distortions to position estimation and MEC spatial representations following shifts to the known locations of familiar distal cues.

海马（HPC）、内侧内嗅皮质（MEC）和压后皮质（RSC）强烈地被激活。 这三种结构的萎缩是阿尔茨海默病的早期指标。在 与记忆过程平行，这些结构对空间认知和这些结构中的神经元很重要。 区域表现出空间特异性激发。当动物在大脑中占据一个明确的位置时，HPC位置细胞就会被激活。 相对于远端视觉标志的环境。MEC神经元编码多种形式的空间信息， 包括网格场，其中单个神经元在跨越整个 形成一个周期性的网格。重要的是， MEC空间模式的功能障碍破坏了 这被认为是情景记忆的基础。 已知鲁棒MEC空间相关的激发需要视觉信息，该视觉信息可能经由 RSC。RSC形成进入该区域的强兴奋性投射，并且像MEC一样，RSC神经元的放电可以被激活。 有节奏，并表现出空间周期性。此外，单个RSC神经元编码感觉、运动和空间神经元。 已知调节MEC激活的变量。虽然众所周知，RSC是视觉的一部分， 处理网络，很少有人知道如何RSC空间表示的影响，安排 远端视觉线索或视觉相关的RSC激活如何反过来影响MEC激活。鉴于 RSC和MEC之间的功能和解剖关系，探索它们的连接是相关的， 此时的神经生理学。 该建议旨在进一步了解MEC和RSC在空间上的系统相互作用 编码.本实验将分析视觉信息在RSC和MEC空间上的影响 通过实现视觉提示操作来扩展或压缩相对表示， 视觉地标之间的角度，而大鼠执行视觉引导导航范例。另夕h 拟议的实验将利用光遗传学来特异性地抑制RSC向MEC的投射，以测试 假设RSC输入是MEC视觉灵敏度所需的。在这些实验中收集的数据将 用于测试有关位置估计和MEC空间失真的计算建模预测 表示后转移到熟悉的远端线索的已知位置。