Hales Jena B, Schlesiger Magdalene I, Leutgeb Jill K, Squire Larry R, Leutgeb Stefan, Clark Robert E
Department of Psychiatry, School of Medicine, University of California, San Diego, La Jolla, CA 92093, USA.
Neurobiology Section and Center for Neural Circuits and Behavior, Division of Biological Sciences, University of California, San Diego, La Jolla, CA 92093, USA.
Cell Rep. 2014 Nov 6;9(3):893-901. doi: 10.1016/j.celrep.2014.10.009. Epub 2014 Oct 30.
The entorhinal cortex provides the primary cortical projections to the hippocampus, a brain structure critical for memory. However, it remains unclear how the precise firing patterns of medial entorhinal cortex (MEC) cells influence hippocampal physiology and hippocampus-dependent behavior. We found that complete bilateral lesions of the MEC resulted in a lower proportion of active hippocampal cells. The remaining active cells had place fields, but with decreased spatial precision and decreased long-term spatial stability. In addition, MEC rats were as impaired in the water maze as hippocampus rats, while rats with combined MEC and hippocampal lesions had an even greater deficit. However, MEC rats were not impaired on other hippocampus-dependent tasks, including those in which an object location or context was remembered. Thus, the MEC is not necessary for all types of spatial coding or for all types of hippocampus-dependent memory, but it is necessary for the normal acquisition of place memory.
内嗅皮质向海马体提供主要的皮质投射，海马体是对记忆至关重要的脑结构。然而，内侧内嗅皮质（MEC）细胞的精确放电模式如何影响海马体生理学和依赖海马体的行为仍不清楚。我们发现，MEC的完全双侧损伤导致活跃海马体细胞的比例降低。其余活跃细胞具有位置野，但空间精度降低且长期空间稳定性下降。此外，MEC损伤的大鼠在水迷宫中的表现与海马体损伤的大鼠一样受损，而MEC和海马体联合损伤的大鼠有更严重的缺陷。然而，MEC损伤的大鼠在其他依赖海马体的任务中并未受损，包括那些涉及记忆物体位置或情境的任务。因此，MEC对于所有类型的空间编码或所有类型的依赖海马体的记忆并非必需，但对于位置记忆的正常获取是必需的。
