Department of Neuroscience, Georgetown University Medical Center, Washington, D.C., USA.
Department of Neurology, Georgetown University Medical Center, Washington, D.C., USA.
J Magn Reson Imaging. 2018 Mar;47(3):682-691. doi: 10.1002/jmri.25816. Epub 2017 Jul 12.
To detect local cholinergic changes in human medial temporal lobe during configural working memory performance.
Proton magnetic resonance spectroscopy ( H-MRS) measurements were acquired at 3T from a 2 × 2 × 3 cm voxel in right medial temporal lobe from 36 subjects during performance of a configural visual working memory task (cWMT). In order to compensate for expected task-based blood oxygenation level-dependent (BOLD) T * effects, resonance signal changes of unbound choline-containing metabolites (Cho) were referenced to an internal standard of creatine + phosphocreatine metabolites (Cre) and compared between four task blocks: rest, memorization, active memory maintenance, and recognition. An unannounced memory retention test was conducted in 21 subjects. Quality assurance analyses examined task-based Cho and Cre individually as well as referenced to resonance signal from N-acetylaspartate (NAA).
Increases from a resting baseline in the Cho/Cre ratio were observed during 60-second blocks of active memory maintenance across the group (P = 0.0042). Behavioral accuracy during task performance correlated with memory retention (r = 0.48, P = 0.027). Quality assurance measures showed task-based changes in Cre resonance signal both individually (P = 0.00099) and when utilized as a noncholinergic internal reference (NAA/Cre, P = 0.00079).
Increases in human medial temporal lobe H-MRS Cho/Cre ratio occur during the maintenance of configural working memory information. However, interpretation of these results as driven by cholinergic activity cannot be assumed, as NAA, a noncholinergic metabolite, shows similar results when utilizing Cre as a reference. Caution is advised when considering Cre as an internal standard for task-based H-MRS measurements.
2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2018;47:682-691.
在人类内侧颞叶进行组态工作记忆表现时，检测局部胆碱能变化。
在 3T 磁共振扫描仪上，对 36 名被试右侧内侧颞叶的一个 2×2×3cm 体素进行质子磁共振波谱（ H-MRS）测量，在执行组态视觉工作记忆任务（ cWMT）期间。为了补偿预期的基于任务的血氧水平依赖（ BOLD ） T *效应，未结合的胆碱含代谢物（ Cho ）的共振信号变化参考内部标准肌酸+磷酸肌酸代谢物（ Cre ），并在四个任务块之间进行比较：休息、记忆、主动记忆维持和识别。在 21 名被试中进行了一项未经宣布的记忆保留测试。质量保证分析分别检查了基于任务的 Cho 和 Cre ，以及参考 N-乙酰天冬氨酸（ NAA ）的共振信号。
在整个组中，在 60 秒的主动记忆维持期间，与静息基线相比， Cho/Cre 比值增加（ P = 0.0042 ）。任务表现的行为准确性与记忆保留相关（ r = 0.48 ， P = 0.027 ）。质量保证措施表明，无论是单独使用（ P = 0.00099 ）还是作为非胆碱能内部参考（ NAA/Cre ， P = 0.00079 ）， Cre 共振信号都会发生基于任务的变化。
在配置工作记忆信息的维持过程中，人类内侧颞叶 H-MRS Cho/Cre 比值增加。然而，不能假设这些结果是由胆碱能活动驱动的，因为当使用 Cre 作为参考时，非胆碱能代谢物 NAA 也会产生类似的结果。在考虑 Cre 作为基于任务的 H-MRS 测量的内部标准时，应谨慎。
2 技术功效：阶段 1 J. Magn. Reson. Imaging 2018 ； 47 ： 682-691.
