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bioRxiv · 10.1101/2023.12.27.573462

Ventral Pallidum and Amygdala Cooperate to Restrain Reward Approach from Overriding Defensive Behaviors

Hernandez-Jaramillo, A.·Illescas-Huerta, E.·Sotres-Bayon, F.
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Abstract

Foraging decisions involve assessing potential risks and prioritizing food sources, which can be challenging when confronted with changing and conflicting circumstances. A crucial aspect of this decision-making process is the ability to actively suppress defensive reactions to threats (fear) and focus on achieving specific goals. The ventral pallidum (VP) and basolateral amygdala (BLA) are two brain regions that play key roles in regulating behavior motivated by either rewards or threats. However, it is unclear whether these regions are necessary in decision-making processes involving competing motivational drives during conflict. Our aim was to investigate the requirements of the VP and BLA for foraging choices in conflicts involving fear suppression. Here, we used a novel foraging task and pharmacological techniques to inactivate either the VP or BLA, or to disconnect these brain regions before conducting a conflict test. Our findings showed that BLA is necessary for making calculated risky choices during conflicts, whereas VP is necessary for invigorating the drive to obtain food, regardless of the presence of conflict. Importantly, our research revealed that the connection between VP and BLA is critical in limiting risk behaviors when searching for food that requires effort in conflict situations. This study provides a new perspective on the collaborative function of VP and BLA in driving behavior, aimed at achieving goals in the face of danger.

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Hernandez-Jaramillo, A., Illescas-Huerta, E., Sotres-Bayon, F.. 2023-12-28. Ventral Pallidum and Amygdala Cooperate to Restrain Reward Approach from Overriding Defensive Behaviors. https://doi.org/10.1101/2023.12.27.573462

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