An emergent neural coactivity code for dynamic memory

Journal article

Neural correlates of external variables provide potential internal codes that guide an animal’s behavior. Notably, first-order features of neural activity, such as single-neuron firing rates, have been implicated in encoding information. However, the extent to which higher-order features, such as multineuron coactivity, play primary roles in encoding information or secondary roles in supporting single-neuron codes remains unclear. Here, we show that millisecond-timescale coactivity among hippocampal CA1 neurons discriminates distinct, short-lived behavioral contingencies. This contingency discrimination was unrelated to the tuning of individual neurons, but was instead an emergent property of their coactivity. Contingency-discriminating patterns were reactivated offline after learning, and their reinstatement predicted trial-by-trial memory performance. Moreover, optogenetic suppression of inputs from the upstream CA3 region during learning impaired coactivity-based contingency information in the CA1 and subsequent dynamic memory retrieval. These findings identify millisecond-timescale coactivity as a primary feature of neural firing that encodes behaviorally relevant variables and supports memory retrieval.

Authors: El-Gaby, M; Reeve, H; Lopes Dos Santos, V; Campo-Urriza, N; Perestenko, P

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Springer Nature
• Journal: Nature Neuroscience
• Volume: 24
• Issue: 5
• Pages: 694-704
• Publication date: 2021-03-29
• Acceptance date: 2021-02-18
• DOI: 10.1038/s41593-021-00820-w
• EISSN: 1546-1726
• ISSN: 1097-6256
• Language: English
• Keywords: FFR