Laboratory of Systems Neuroscience, Department of Physiology, University of Bern, Bern, Switzerland.
Sci Adv. 2023 Jun 2;9(22):eadg4881. doi: 10.1126/sciadv.adg4881. Epub 2023 May 31.
Extinction memory retrieval is influenced by spatial contextual information that determines responding to conditioned stimuli (CS). However, it is poorly understood whether contextual representations are imbued with emotional values to support memory selection. Here, we performed activity-dependent engram tagging and in vivo single-unit electrophysiological recordings from the ventral hippocampus (vH) while optogenetically manipulating basolateral amygdala (BLA) inputs during the formation of cued fear extinction memory. During fear extinction when CS acquire safety properties, we found that CS-related activity in the vH reactivated during sleep consolidation and was strengthened upon memory retrieval. Moreover, fear extinction memory was facilitated when the extinction context exhibited precise coding of its affective zones. Last, these activity patterns along with the retrieval of the fear extinction memory were dependent on glutamatergic transmission from the BLA during extinction learning. Thus, fear extinction memory relies on the formation of contextual and stimulus safety representations in the vH instructed by the BLA.
灭绝记忆检索受到空间上下文信息的影响，这些信息决定了对条件刺激 (CS) 的反应。然而，对于上下文表示是否具有情感价值以支持记忆选择，人们知之甚少。在这里，我们在条件性恐惧消退记忆形成过程中，通过光遗传方法对伏隔核 (vH) 中的基底外侧杏仁核 (BLA) 输入进行操作，并进行了依赖于活动的记忆标签标记和体内单细胞电生理记录。当 CS 获得安全属性时，在恐惧消退期间，我们发现 vH 中的 CS 相关活动在睡眠巩固期间重新激活，并在记忆检索时得到增强。此外，当消退环境精确编码其情感区域时，恐惧消退记忆会得到促进。最后，这些活动模式以及恐惧消退记忆的检索依赖于消退学习期间 BLA 中的谷氨酸能传递。因此，恐惧消退记忆依赖于 BLA 指导的 vH 中上下文和刺激安全表示的形成。
