Memory reorganization in the ACC and thalamus

在上个世纪，记忆一直是许多研究的焦点，但仍有许多未被理解。科学家发现，随着时间的推移，记忆会通过一个被称为巩固的过程而稳定下来。有人提出存在两种类型的合并。第一种类型是细胞巩固，发生在几分钟到几小时内，被认为涉及神经细胞之间连接的重新布线。第二种类型，系统巩固，涉及在更长的时间框架内在大脑结构的整体水平上的额外变化。因此，最初依赖于被称为海马体的大脑结构的记忆随着时间的推移会依赖于其他结构。一个多世纪以来，科学家们认为巩固的记忆是永久稳定的，这意味着记忆在两个层次上只巩固一次。然而，最近的研究结果表明，巩固的记忆在被记住时可能会回到不稳定的状态。在这种状态下，存储器可以被改变、擦除或通过一个称为再巩固的过程重新稳定。当记忆不再依赖海马体时，这种现象也会发生在系统层面（系统再巩固）。细胞和系统再巩固的这些发现因此挑战了巩固的标准观点。最近，许多研究表明，被称为内侧前额叶皮层（mPFC）的特定区域，如前扣带皮层（ACC），调节远程记忆的检索。此外，层间丘脑核（ILN），一组位于另一个被称为丘脑的大脑结构中的核，最近也被证明与系统巩固有关。然而，ACC和ILN在细胞和系统再巩固中的作用尚未被研究。因此，该提案将结合行为和分子研究来测试ACC和ILN是否经历细胞和系统的再巩固。这将提供对这些过程的更好理解，以及这些大脑结构如何在常规基础上一起工作的知识。

Memory has been the focus of a lot of research in the last century, but much is still not understood. Scientists have found that memories are stabilized over time through a process called consolidation. Two types of consolidation have been proposed to exist. The first type, cellular consolidation, occurs over minutes to hours and is thought to involve rewiring the connections between nerve cells. The second type, systems consolidation, involves additional changes at the global level of brain structures over a much longer time frame. As such, memories that are initially dependent on a brain structure called the hippocampus become dependent on other structures over time. For over a century, scientists believed that consolidated memories were permanently stabilized, implying that memories were consolidated at both levels only once. However, recent findings have shown that a consolidated memory can return to an unstable state when it when it is remembered. In this state, the memory can be altered, erased or restabilized through a process called reconsolidation. This phenomenon can also take place at the systems level (systems reconsolidation), when a memory no longer depends on the hippocampus. These findings of cellular and systems reconsolidation have thus challenged the standard view of consolidation. Recently, a number of studies have shown that specific regions in what is called the medial prefrontal cortex (mPFC), such as the anterior cingulate cortex (ACC), mediate retrieval of remote memories. Furthermore, the intralaminar thalamic nuclei (ILN), a group of nuclei in another brain structure called the thalamus, have also recently been shown to be involved in systems consolidation. However, the roles of the ACC and the ILN in cellular and systems reconsolidation have not yet been investigated. This proposal will therefore combine behavioral and molecular studies to test whether the ACC and ILN undergo cellular and systems reconsolidation. This would provide a better understanding of these processes, as well as knowledge on how these brain structures function together on a regular basis.