de Chastelaine Marianne, Mattson Julia T, Wang Tracy H, Donley Brian E, Rugg Michael D
Center for Vital Longevity and School of Behavioral and Brain Sciences, The University of Texas at Dallas, Dallas, TX 75235, USA.
UT Southwestern Medical Center, Dallas, TX 75390, USA.
Neuroimage. 2017 Aug 1;156:340-351. doi: 10.1016/j.neuroimage.2017.05.039. Epub 2017 May 19.
The impact of age on the neural correlates of familiarity-driven recognition memory has received relatively little attention. Here, the relationships between age, the neural correlates of familiarity, and memory performance were investigated using an associative recognition test in young, middle-aged and older participants. Test items comprised studied, rearranged (items studied on different trials) and new word pairs. fMRI 'familiarity effects' were operationalized as greater activity for studied test pairs incorrectly identified as 'rearranged' than for correctly rejected new pairs. The reverse contrast was employed to identify 'novelty' effects. Estimates of familiarity strength were slightly but significantly lower for the older relative to the younger group. With the exception of one region in dorsal medial prefrontal cortex, fMRI familiarity effects (which were identified in medial and lateral parietal cortex, dorsal medial and left lateral prefrontal cortex, and bilateral caudate among other regions) did not differ significantly with age. Age-invariant 'novelty effects' were identified in the anterior hippocampus and the perirhinal cortex. When entered into the same regression model, familiarity and novelty effects independently predicted familiarity strength across participants, suggesting that the two classes of memory effect reflect functionally distinct mnemonic processes. It is concluded that the neural correlates of familiarity-based memory judgments, and their relationship with familiarity strength, are largely stable across much of the healthy adult lifespan.
年龄对基于熟悉度的识别记忆的神经关联的影响相对较少受到关注。在此，通过对年轻、中年和老年参与者进行联想识别测试，研究了年龄、熟悉度的神经关联与记忆表现之间的关系。测试项目包括已学习的、重新排列的（在不同试验中学习的项目）和新的单词对。功能磁共振成像（fMRI）的“熟悉度效应”定义为，被错误识别为“重新排列”的已学习测试对的活动比正确排除的新对的活动更强。采用相反的对比来识别“新颖性”效应。与年轻组相比，老年组的熟悉度强度估计值略低但具有显著差异。除了背内侧前额叶皮层的一个区域外，fMRI的熟悉度效应（在内侧和外侧顶叶皮层、背内侧和左侧外侧前额叶皮层以及双侧尾状核等区域被识别）在年龄上没有显著差异。在海马前部和鼻周皮层中发现了与年龄无关的“新颖性效应”。当纳入同一个回归模型时，熟悉度和新颖性效应独立预测了参与者的熟悉度强度，这表明这两类记忆效应反映了功能上不同的记忆过程。得出的结论是，基于熟悉度的记忆判断的神经关联及其与熟悉度强度的关系在健康成年人的大部分生命周期中基本稳定。
