Interdisciplinary Graduate Program in Neuroscience, University of Iowa, Iowa City, IA 52242, United States.
Department of Psychological and Brain Sciences, University of Iowa, Iowa City, IA 52242, United States.
Neurobiol Learn Mem. 2024 Nov;215:107988. doi: 10.1016/j.nlm.2024.107988. Epub 2024 Oct 5.
The basolateral amygdala (BLA) modulates different types of memory consolidation via distinct projections to downstream brain regions in multiple memory systems. Prior studies indicate that the BLA projects to the nucleus accumbens shell (NAshell) and that these regions interact to influence some types of behavior. Moreover, previous pharmacological work suggests the BLA and NAshell interact to influence memory. However, the precise role of the BLA-NAshell pathway has never been directly investigated in the consolidation of different types of memory including cued-response, spatial, or inhibitory avoidance (IA) learning. To address this, male and female Sprague-Dawley rats received optogenetic manipulations of the BLA or BLA-NAshell pathway immediately following training in different learning tasks. An initial experiment found that optogenetically inhibiting the BLA itself immediately after training impaired cued-response retention in a Barnes maze task in males and females, confirming earlier pharmacological work in males alone. Subsequent experiments found that BLA-NAshell pathway inhibition impaired retention of cued-response and IA learning but had no effect on retention of spatial learning. However, the present work did not observe any effects of pathway stimulation immediately after cued-response or IA learning. Together, the present findings suggest the BLA modulates the consolidation of cued-response and IA, but not spatial, memory consolidation via NAshell projections.
外侧杏仁核(BLA)通过向多个记忆系统中的下游脑区投射不同的投射来调节不同类型的记忆巩固。先前的研究表明,BLA 投射到伏隔核壳(NAshell),这些区域相互作用以影响某些类型的行为。此外,先前的药理学研究表明,BLA 和 NAshell 相互作用以影响记忆。然而,BLA-NAshell 通路在不同类型记忆的巩固中的精确作用,包括提示反应、空间或抑制性回避(IA)学习,从未被直接研究过。为了解决这个问题,雄性和雌性 Sprague-Dawley 大鼠在不同的学习任务中接受了 BLA 或 BLA-NAshell 通路的光遗传学操作,这些操作是在训练后立即进行的。一项初步实验发现,在雄性和雌性大鼠的 Barnes 迷宫任务中,在训练后立即用光遗传学抑制 BLA 本身会损害提示反应的保留,这证实了先前在雄性大鼠中进行的药理学研究。随后的实验发现,BLA-NAshell 通路抑制会损害提示反应和 IA 学习的保留,但对空间学习的保留没有影响。然而,目前的工作并没有观察到在提示反应或 IA 学习后立即刺激通路的任何影响。总之,目前的研究结果表明,BLA 通过 NAshell 投射调节提示反应和 IA,但不调节空间记忆的巩固。