Aghjayan Sarah L, Polk Sarah E, Ripperger Hayley S, Huang Haiqing, Wan Lu, Kamarck Thomas, Marsland Anna L, Kang Chaeryon, Voss Michelle W, Sutton Bradley P, Oberlin Lauren E, Burns Jeffrey M, Vidoni Eric D, McAuley Edward, Hillman Charles H, Kramer Arthur F, Erickson Kirk I
Department of Psychology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
Center for Lifespan Psychology, Max Planck Institute for Human Development, Berlin, Germany.
Hippocampus. 2025 Mar;35(2):e70010. doi: 10.1002/hipo.70010.
Different tasks of episodic memory (EM) are only moderately correlated with each other. Furthermore, various EM tasks exhibit disproportional relationships with the hippocampus. This study examined the covariance structure of EM tasks and assessed whether this structure relates differently to hippocampal volume (HV) in a sample of 648 cognitively unimpaired older adults (mean age = 69.88). A confirmatory factor analysis (CFA) and linear regression models were used to test the associations between the observed factors of EM and HV. A model with three first-order subfactors (immediate verbal recall, delayed verbal recall, and visuospatial) derived from a second-order EM domain factor satisfied model fit (χ p value ≥ 0.05, CFI > 0.90, RMSEA < 0.08, SRMR < 0.08). Total, left, and right HV explained a similar amount of variance in all EM subfactors. CA1, CA3, subiculum, and entorhinal cortex volume were associated with all subfactors, while CA2 and dentate gyrus volume were not associated with EM. These results suggest that EM tasks are measuring the same construct, but different complex processes contribute to EM. Furthermore, HV accounted for a small portion of the variance in EM, suggesting that HV might not be a useful marker of EM in cognitively unimpaired older adults. Finally, this study provides evidence that various hippocampal subfield volumes may not be purely associated with any one aspect of EM processing.
情景记忆（EM）的不同任务之间仅具有中等程度的相关性。此外，各种EM任务与海马体呈现出不成比例的关系。本研究考察了EM任务的协方差结构，并评估了在648名认知未受损的老年人（平均年龄 = 69.88岁）样本中，这种结构与海马体体积（HV）的关系是否不同。采用验证性因素分析（CFA）和线性回归模型来检验EM的观测因素与HV之间的关联。一个从二阶EM领域因素派生的具有三个一阶子因素（即时言语回忆、延迟言语回忆和视觉空间）的模型满足模型拟合度（χ² p值≥0.05，CFI > 0.90，RMSEA < 0.08，SRMR < 0.08）。总的、左侧和右侧的HV在所有EM子因素中解释的方差量相似。CA1、CA3、海马下托和内嗅皮质体积与所有子因素相关，而CA2和齿状回体积与EM无关。这些结果表明，EM任务测量的是相同的结构，但不同的复杂过程对EM有贡献。此外，HV在EM方差中占比很小，这表明在认知未受损的老年人中，HV可能不是EM的一个有用标志物。最后，本研究提供了证据表明，各种海马亚区体积可能并非纯粹与EM处理的任何一个方面相关。
