Perry Brook A L, Mitchell Anna S
Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom.
Front Mol Neurosci. 2019 Jul 3;12:167. doi: 10.3389/fnmol.2019.00167. eCollection 2019.
Our memories are essential in our daily lives. The frontal and cingulate cortices, hippocampal system and medial temporal lobes are key brain regions. In addition, severe amnesia also occurs after damage or dysfunction to the anterior thalamic nuclei; this subcortical thalamic hub is interconnected to these key cortical memory structures. Behavioral, anatomical, and physiological evidence across mammalian species has shown that interactions between the anterior thalamic nuclei, cortex and hippocampal formation are vital for spatial memory processing. Furthermore, the adjacent laterodorsal thalamic nucleus (LD), interconnected to the retrosplenial cortex (RSC) and visual system, also contributes to spatial memory in mammals. However, how these thalamic nuclei contribute to memory still remains largely unknown. Fortunately, our understanding of the importance of the thalamus in cognitive processes is being redefined, as widespread evidence challenges the established view of the thalamus as a passive relay of sensory and subcortical information to the cortex. In this review article, we examine whether the anterior thalamic nuclei and the adjacent LD are suitable candidates for "higher-order" thalamic nuclei, as defined by the Sherman and Guillery model. Rather than simply relaying information to cortex, "higher-order" thalamic nuclei have a prominent role in cognition, as they can regulate how areas of the cortex interact with one another. These considerations along with a review of the latest research will be used to suggest future studies that will clarify the contributions that the anterior and LD have in supporting cortical functions during cognitive processes.
我们的记忆在日常生活中至关重要。额叶和扣带回皮质、海马系统以及内侧颞叶是关键的脑区。此外，丘脑前核受损或功能障碍后也会出现严重失忆；这个皮质下丘脑枢纽与这些关键的皮质记忆结构相互连接。跨哺乳动物物种的行为、解剖学和生理学证据表明，丘脑前核、皮质和海马结构之间的相互作用对于空间记忆处理至关重要。此外，与压后皮质（RSC）和视觉系统相互连接的相邻背外侧丘脑核（LD）也对哺乳动物的空间记忆有贡献。然而，这些丘脑核如何对记忆产生影响在很大程度上仍然未知。幸运的是，随着广泛的证据挑战了丘脑作为感觉和皮质下信息向皮质的被动中继站这一既定观点，我们对丘脑在认知过程中的重要性的理解正在被重新定义。在这篇综述文章中，我们根据谢尔曼和吉利里模型，研究丘脑前核和相邻的LD是否适合作为“高阶”丘脑核的候选者。“高阶”丘脑核并非简单地将信息中继到皮质，而是在认知中发挥着重要作用，因为它们可以调节皮质区域之间的相互作用方式。这些考量以及对最新研究的综述将用于建议未来的研究，以阐明丘脑前核和LD在认知过程中对支持皮质功能所做的贡献。
