Pudas Sara, Persson Jonas, Nilsson Lars-Göran, Nyberg Lars
Department of Psychology, Stockholm University, Stockholm, Sweden; Department of Integrative Medical Biology (Physiology), Umeå University, Umeå, Sweden; Umeå Center for Functional Brain Imaging, Umeå University, Umeå, Sweden.
Department of Psychology, Stockholm University, Stockholm, Sweden; Umeå Center for Functional Brain Imaging, Umeå University, Umeå, Sweden; Aging Research Center, Karolinska Institute and Stockholm University, Stockholm, Sweden.
Neurobiol Aging. 2014 Nov;35(11):2495-2503. doi: 10.1016/j.neurobiolaging.2014.05.022. Epub 2014 May 29.
Cross-sectional neuroimaging studies suggest that hippocampal and prefrontal cortex functions underlie individual differences in memory ability in older individuals, but it is unclear how individual differences in cognitive ability in youth contribute to cognitive and neuroimaging measures in older age. Here, we investigated the relative influences of midlife memory ability and age-related memory change on memory-related BOLD-signal variability at one time point, using a sample from a longitudinal population-based aging study (N = 203, aged 55-80 years). Hierarchical regression analyses showed that midlife memory ability, assessed 15-20 years earlier, explained at least as much variance as memory change in clusters in the left inferior prefrontal cortex and the bilateral hippocampus, during memory encoding. Furthermore, memory change estimates demonstrated higher sensitivity than current memory levels in identifying distinct frontal regions where activity was selectively related to age-related memory change, as opposed to midlife memory. These findings highlight challenges in interpreting individual differences in neurocognitive measures as age-related changes in the absence of longitudinal data and also demonstrate the improved sensitivity of longitudinal measures.
横断面神经影像学研究表明，海马体和前额叶皮层功能是老年人记忆能力个体差异的基础，但尚不清楚年轻时认知能力的个体差异如何影响老年人的认知和神经影像学指标。在此，我们使用一项基于人群的纵向衰老研究样本（N = 203，年龄55 - 80岁），在一个时间点研究中年记忆能力和年龄相关记忆变化对记忆相关BOLD信号变异性的相对影响。分层回归分析表明，15 - 20年前评估的中年记忆能力在记忆编码过程中，解释的方差至少与左侧前额叶下回和双侧海马体簇中的记忆变化一样多。此外，在识别与年龄相关记忆变化而非中年记忆选择性相关的不同额叶区域时，记忆变化估计比当前记忆水平表现出更高的敏感性。这些发现凸显了在缺乏纵向数据的情况下，将神经认知指标中的个体差异解释为年龄相关变化所面临的挑战，同时也证明了纵向测量具有更高的敏感性。
