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bioRxiv · 10.1101/2023.10.10.561506

Threat-dependent scaling of prelimbic dynamics to enhance fear representation

Casanova, J. P.·Pouget, C.·Treiber, N.·Agarwal, I.·Brimble, M. A.·Vetere, G.
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Abstract

Promptly identifying threatening stimuli is crucial for survival. Freezing is a natural behavior displayed by rodents towards potential or actual threats. While it is known that the prelimbic cortex (PL) is involved in both risk evaluation and in fear and anxiety-like behavior expression, here we explored whether PL neuronal activity can dynamically represent different internal states of the same behavioral output. We found that freezing can always be decoded from PL activity at a population level. However, the sudden presentation of a fearful stimulus quickly reshaped PL to a new neuronal activity state, an effect not observed in other cortical or subcortical regions. This shift changed PL freezing representation and is necessary for fear memory expression. Our data reveal the unique role of PL in detecting threats and internally adjusting to distinguish between different freezing-related states. IN BRIEFThrough a comparative analysis across brain regions and risk situations, we demonstrate the distinctive role of the Prelimbic Cortex (PL) in fear-related behavior representation: the PL promptly detects threat stimuli and adjusts its neuronal configuration accordingly, resulting in a change in freezing representation, which is necessary for memory-associated fear expression. HIGHLIGHTS- PL population activity represents fear-related behavior (i.e., freezing) - Same behavioral outcome (freezing) can be represented as different PL neuronal states - Other brain regions do not show changes in dynamics to represent freezing - PL dynamics following threats are necessary for proper fear memory expression

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Casanova, J. P., Pouget, C., Treiber, N., Agarwal, I., Brimble, M. A., Vetere, G.. 2023-10-10. Threat-dependent scaling of prelimbic dynamics to enhance fear representation. https://doi.org/10.1101/2023.10.10.561506

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