Department of Psychology, University of Toronto, 100 St. George Street, Toronto, ON M5S 3G3, Canada.
Neuron. 2011 Dec 22;72(6):931-7. doi: 10.1016/j.neuron.2011.10.014.
The hippocampus is known to support recollection memory, but the relation between its structure and recollection in healthy adults has not been established. Here we show that the hippocampus (including subiculum, DG, and CA1-CA4), when separated into posterior and anterior segments, can reliably predict recollection in healthy young adults. Better memory was associated with larger posterior and smaller anterior segments, as evaluated relative to the uncal apex. Overall hippocampal volume, however, did not predict memory. This pattern was confirmed in four separate data sets from different studies and laboratories. The relationship between the posterior hippocampus and memory was mediated by the structure's functional connectivity with a neocortical network identified during a postencoding resting-state scan. The relationship was also weakest in an experiment involving no appreciable study-test interval. These findings suggest that enhanced posterior-hippocampal postencoding processes may account for the memory benefit associated with larger posterior hippocampi.
海马体被认为支持回忆记忆，但它的结构与健康成年人的回忆之间的关系尚未确定。在这里，我们表明，当将海马体（包括下托、DG 和 CA1-CA4）分为后段和前段时，可以可靠地预测健康年轻成年人的回忆。与相对尖顶的关系相比，更好的记忆与更大的后段和更小的前段相关。然而，总的海马体体积并不能预测记忆。这种模式在来自不同研究和实验室的四个独立数据集得到了证实。后海马体与记忆之间的关系是由其与在编码后静息状态扫描中识别出的新皮层网络的功能连接介导的。在后一个实验中，由于没有明显的学习-测试间隔，这种关系也最弱。这些发现表明，增强的后海马体后编码过程可能解释了与较大的后海马体相关的记忆益处。
