Barcoding of episodic memories in the hippocampus of a food-caching bird

The hippocampus is critical for episodic memory. Although hippocampal activity represents place and other behaviorally relevant variables, it is unclear how it encodes numerous memories of specific events in life. To study episodic coding, we leveraged the specialized behavior of chickadees – food-caching birds that form memories at well-defined moments in time whenever they cache food for subsequent retrieval. Our recordings during caching revealed very sparse, transient barcode-like patterns of firing across hippocampal neurons. Each “barcode” uniquely represented a caching event and transiently reactivated during the retrieval of that specific cache. Barcodes co-occurred with the conventional activity of place cells, but were uncorrelated even for nearby cache locations that had similar place codes. We propose that animals recall episodic memories by reactivating hippocampal barcodes. Similarly to computer hash codes, these patterns assign unique identifiers to different events and c..., Raw electrophysiological, calcium imaging, and behavioral video recordings during food caching behavior in chickadee hippocampus were collected and pre-processed as described in the associated manuscript. , , # Barcoding of episodic memories in the hippocampus of a food-caching bird [https://doi.org/10.5061/dryad.7h44j101z](https://doi.org/10.5061/dryad.7h44j101z) This repository contains all data used in the accompanying paper. This includes behavioral tracking and annotation of food caching behavior, electrophysiology, and calcium imaging data. Further details on the experiments, data and methods are available in the paper, published in Cell (April 11, 2024) and available as a free pre-print at: [https://www.biorxiv.org/content/10.1101/2023.05.27.542597v2](https://www.biorxiv.org/content/10.1101/2023.05.27.542597v2) ## Description of the data and file structure Electrophysiology experiments in the grid arena are in `Grid Caching Data` with documentation in a README.m file (provided outside of the zipped archive), and imaging experiments in the circular arena are in `Circular Arena Data` with documentation in a Word doc ('Calcium imaging documentation' - also outside the zipped archive)...海马体对于情景记忆（episodic memory）至关重要。尽管海马体活动编码了位置及其他与行为相关的变量，但目前尚不清楚其如何编码生活中大量特定事件的记忆。为研究情景编码机制，我们利用了山雀的特殊行为——这类储食鸟类会在储食以备后续取回的明确时间节点形成记忆。我们在储食过程中开展的记录显示，海马神经元群体的放电呈现出高度稀疏、类似条形码的瞬时模式。每一个“条形码”都唯一表征了一次储食事件，并在取回该特定储藏品时瞬时重新激活。这类条形码与位置细胞的常规活动同步出现，但即便对于位置编码相似的邻近储食位点，其条形码也互不相关。我们提出，动物通过重新激活海马体条形码来回忆情景记忆。这一机制与计算机哈希码（hash code）类似，这些模式为不同事件和储食行为分配唯一标识符…… 本数据集采集并预处理了山雀海马体在储食行为过程中的原始电生理、钙成像以及行为视频记录，具体流程详见相关论文。 # 储食鸟类海马体的情景记忆条形码编码 https://doi.org/10.5061/dryad.7h44j101z 本仓库包含伴随论文所用的全部数据，涵盖储食行为的行为追踪与标注、电生理数据以及钙成像数据。关于实验、数据与方法的更多细节可参阅发表于《细胞》（Cell，2024年4月11日）的论文，亦可在预印本平台免费获取：https://www.biorxiv.org/content/10.1101/2023.05.27.542597v2 ## 数据与文件结构说明 网格箱储食实验的数据位于`Grid Caching Data`文件夹，相关说明文档存于README.m文件（位于压缩包外部）；圆形箱钙成像实验的数据位于`Circular Arena Data`文件夹，相关说明文档为Word文档《Calcium imaging documentation》（同样位于压缩包外部）。