Anatomical organization of temporally correlated neural calcium activity in the hippocampal CA1 region

• Published in: iScience Vol. 26; no. 5; p. 106703
• Main Authors: Chen, Lujia, Lin, Xiaoxiao, Ye, Qiao, Nenadic, Zoran, Holmes, Todd C., Nitz, Douglas A., Xu, Xiangmin
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 19.05.2023; Elsevier
• Subjects: Cellular neuroscience; Molecular neuroscience; Neuroscience; Molecular neuroscience; Cellular neuroscience; Neuroscience
• ISSN: 2589-0042; 2589-0042
• DOI: 10.1016/j.isci.2023.106703

Hippocampal CA1 neuronal ensembles generate sequential patterns of firing activity that contribute to episodic memory formation and spatial cognition. Here we used in vivo calcium imaging to record neural ensemble activities in mouse hippocampal CA1 and identified CA1 excitatory neuron sub-populations whose members are active across the same second-long period of time. We identified groups of hippocampal neurons sharing temporally correlated neural calcium activity during behavioral exploration and found that they also organized as clusters in anatomical space. Such clusters vary in membership and activity dynamics with respect to movement in different environments, but also appear during immobility in the dark suggesting an internal dynamic. The strong covariance between dynamics and anatomical location within the CA1 sub-region reveals a previously unrecognized form of topographic representation in hippocampus that may guide generation of hippocampal sequences across time and therefore organize the content of episodic memory. [Display omitted] •Temporally correlated CA1 pyramidal cells are organized into anatomical clusters•Ensemble activities of intra-cluster cells cover different regions of environment•Anatomical clusters reorganize during obvious environment change•Anatomical clusters continue to exist during immobility in a dark environment Neuroscience; Molecular neuroscience; Cellular neuroscience