Prefrontal neuronal ensembles link prior knowledge with novel actions during flexible action selection

• Published in: Cell reports (Cambridge) Vol. 42; no. 12; p. 113492
• Main Authors: Jarovi, Justin, Pilkiw, Maryna, Takehara-Nishiuchi, Kaori
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 26-12-2023; Elsevier
• Subjects: Animals; cell assembly; CP: Neuroscience; Cues; decision-making; ensemble recording; hippocampus; Hippocampus - physiology; inference; medial prefrontal cortex; Neurons - physiology; Prefrontal Cortex - physiology; Rats; relational memory; replay; ripples; Wakefulness; cell assembly; ripples; medial prefrontal cortex; inference; hippocampus; decision-making; CP: Neuroscience; ensemble recording; replay; rats; relational memory
• ISSN: 2211-1247; 2211-1247
• DOI: 10.1016/j.celrep.2023.113492

We make decisions based on currently perceivable information or an internal model of the environment. The medial prefrontal cortex (mPFC) and its interaction with the hippocampus have been implicated in the latter, model-based decision-making; however, the underlying computational properties remain incompletely understood. We have examined mPFC spiking and hippocampal oscillatory activity while rats flexibly select new actions using a known associative structure of environmental cues and outcomes. During action selection, the mPFC reinstates representations of the associative structure. These awake reactivation events are accompanied by synchronous firings among neurons coding the associative structure and those coding actions. Moreover, their functional coupling is strengthened upon the reactivation events leading to adaptive actions. In contrast, only cue-coding neurons improve functional coupling during hippocampal sharp wave ripples. Thus, the lack of direct experience disconnects the mPFC from the hippocampus to independently form self-organized neuronal ensemble dynamics linking prior knowledge with novel actions.
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•Rats use previously learned rules to select new adaptive actions without direct experience•During the action selection, prefrontal neurons reactivate representations of the rules•Rule reactivation leads to multi-neuron coactivity linking the rules and selected actions•The strength of the coactivity is not modulated by hippocampal sharp wave ripples
Prior knowledge allows for choosing a new action based on its inferred consequence. Jarovi et al. have developed a behavioral task to model this process in rats and show that neurons in the medial prefrontal cortex transiently couple spiking activity with one another to link prior knowledge with new actions.