When faced with changing contingencies, animals can use memory to flexibly guide actions, engaging both frontal and temporal lobe brain structures. Damage to the hippocampus (HPC) impairs episodic memory, and damage to the prefrontal cortex (PFC) impairs cognitive flexibility, but the circuit mechanisms by which these areas support flexible memory processing remain unclear. The present study investigated these mechanisms by temporarily inactivating the medial PFC (mPFC), the dorsal HPC (dHPC), and the ventral HPC (vHPC), individually and in combination, as rats learned spatial discriminations and reversals in a plus maze. Bilateral inactivation of either the dHPC or vHPC profoundly impaired spatial learning and memory, whereas bilateral mPFC inactivation primarily impaired reversal versus discrimination learning. Inactivation of unilateral mPFC together with the contralateral dHPC or vHPC impaired spatial discrimination and reversal learning, whereas ipsilateral inactivation did not. Flexible spatial learning thus depends on both the dHPC and vHPC and their functional interactions with the mPFC.

中文翻译：

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灵活的空间学习需要背侧和腹侧海马体及其与前额皮质的功能相互作用。


当面对不断变化的突发事件时，动物可以利用记忆灵活地指导行动，调动额叶和颞叶的大脑结构。海马体 (HPC) 损伤会损害情景记忆，前额皮质 (PFC) 损伤会损害认知灵活性，但这些区域支持灵活记忆处理的回路机制仍不清楚。本研究通过暂时使内侧 PFC (mPFC)、背侧 HPC (dHPC) 和腹侧 HPC (vHPC) 单独或组合失活来研究这些机制，因为大鼠在正号迷宫中学习空间辨别和逆转。 dHPC 或 vHPC 的双侧失活严重损害了空间学习和记忆，而双侧 mPFC 失活主要损害逆转学习和辨别学习。单侧 mPFC 与对侧 dHPC 或 vHPC 失活会损害空间辨别和逆转学习，而同侧失活则不会。因此，灵活的空间学习取决于 dHPC 和 vHPC 及其与 mPFC 的功能相互作用。