a Department of Neurology , University of California , San Francisco , CA , USA.
b Memory and Aging Center , University of California , San Francisco , CA , USA.
Clin Neuropsychol. 2018 Apr;32(3):456-467. doi: 10.1080/13854046.2017.1370134. Epub 2017 Aug 31.
Traditional episodic memory tests employ a delayed recall length ranging from 10 to 30 min. The neurobiological process of memory consolidation extends well beyond these time intervals, however, raising the possibility that these tests might not be fully sensitive to the subtle neurocognitive changes found in early disease or age-related decline. We aimed to determine the sensitivity of a 1-week delayed recall paradigm to medial temporal lobe (MTL) structure among neurologically normal older adults.
One hundred and forty functionally intact, older adults (mean age = 75.8) completed a story recall test in which participants learned to 90% criterion. Recall was tested after 30-min and 1-week. Participants also completed a standardized list learning task with a 20-min delay (n = 129) and a structural brain MRI. The MTL, including the parahippocampal gyrus, hippocampus, and entorhinal, was our primary region of interest.
Controlling for age, education, gender and total intracranial volume, the standard 20- and 30-min recalls showed no significant relationship with MTL. In contrast, 1-week recall was uniquely associated with MTL structure (partial r = .24, p = .006), specifically entorhinal (partial r = .27; p = .001) and hippocampal (partial r = .21, p = .02) volumes.
Memory paradigms that utilize 1-week delays are more sensitive than standard paradigms to MTL volumes in neurologically normal older adults. Longer delay periods may improve detection of memory consolidation abilities associated with age-related, and potentially pathological, neurobehavioral change.
传统的情景记忆测试采用的延迟回忆时长为 10 至 30 分钟。然而，记忆巩固的神经生物学过程远远超出了这些时间间隔，这使得这些测试可能无法完全敏感地发现早期疾病或与年龄相关的认知能力下降中细微的神经认知变化。我们旨在确定一周延迟回忆范式对神经认知正常的老年人内侧颞叶（MTL）结构的敏感性。
140 名功能完整的老年人（平均年龄=75.8 岁）完成了一个故事回忆测试，参与者学习至 90%的标准。在 30 分钟和 1 周后进行回忆测试。参与者还完成了一项具有 20 分钟延迟的标准化列表学习任务（n=129）和结构脑 MRI。MTL 包括旁海马回、海马体和内嗅皮层，是我们的主要感兴趣区域。
在控制年龄、教育程度、性别和总颅内体积后，标准的 20 分钟和 30 分钟回忆与 MTL 无显著关系。相比之下，一周后的回忆与 MTL 结构（偏相关 r=0.24，p=0.006），特别是内嗅皮层（偏相关 r=0.27；p=0.001）和海马体（偏相关 r=0.21，p=0.02）体积具有独特的相关性。
在神经认知正常的老年人中，使用一周延迟的记忆范式比标准范式更能敏感地检测到与年龄相关的、潜在病理性神经行为变化相关的记忆巩固能力。更长的延迟期可能会提高对与年龄相关的、潜在病理性神经行为变化相关的记忆巩固能力的检测能力。
