Rodrigue Karen M, Raz Naftali
Institute of Gerontology and Department of Psychology, Wayne State University, Detroit, Michigan 48202, USA.
J Neurosci. 2004 Jan 28;24(4):956-63. doi: 10.1523/JNEUROSCI.4166-03.2004.
Lesions in the hippocampus (HC), the entorhinal cortex (EC), and the prefrontal cortex (PFC) are associated with impairment of episodic memory; reduced HC volume is linked to memory declines in dementia; and decline in EC volume predicts progression from mild cognitive impairment to dementia. However, in healthy adults, the relationship between memory and regional volumes is unclear, and no data are available on the relationship of longitudinal regional shrinkage to memory performance in a cognitively intact population. The objective of this study was to examine whether shrinkage of the EC, HC, and PFC over a 5 year period can predict declarative memory performance in healthy adults. The volumes of three brain regions were measured on magnetic resonance images that were acquired twice, 5 years apart. Multiple measures of episodic memory were administered at follow-up. Results indicated that the volume of HC and PFC (but not EC) correlated with age at baseline and follow-up. However, after age differences in memory were taken into account, none of the regional volumes was associated with memory performance at follow-up. In contrast, greater annual rate of shrinkage in EC (but not HC or PFC) predicted poorer memory performance. Thus, in a healthy and educated population, even mild age-related shrinkage of the EC may be a sensitive predictor of memory decline.
海马体（HC）、内嗅皮质（EC）和前额叶皮质（PFC）的病变与情景记忆受损有关；海马体体积减小与痴呆症患者的记忆衰退有关；内嗅皮质体积减小预示着从轻度认知障碍向痴呆症的进展。然而，在健康成年人中，记忆与区域体积之间的关系尚不清楚，而且在认知功能正常的人群中，关于纵向区域萎缩与记忆表现之间的关系尚无数据。本研究的目的是检验在5年时间里，内嗅皮质、海马体和前额叶皮质的萎缩是否能够预测健康成年人的陈述性记忆表现。在相隔5年采集的两次磁共振图像上测量了三个脑区的体积。在随访时进行了多项情景记忆测量。结果表明，海马体和前额叶皮质（而非内嗅皮质）的体积与基线和随访时的年龄相关。然而，在考虑了记忆方面的年龄差异后，没有一个区域体积与随访时的记忆表现相关。相比之下，内嗅皮质（而非海马体或前额叶皮质）每年更大的萎缩率预示着更差的记忆表现。因此，在健康且受过教育的人群中，即使是内嗅皮质与年龄相关的轻度萎缩也可能是记忆衰退的一个敏感预测指标。
