Maillet David, Rajah M Natasha
Department of Neuroscience, McGill University, Montreal, QC H3A 2T5, Canada.
Douglas Mental Health University Institute and Department of Psychiatry, McGill University, Montreal, QC H4H 1R3, Canada.
Neurosci Biobehav Rev. 2014 Sep;45:246-57. doi: 10.1016/j.neubiorev.2014.06.006. Epub 2014 Jun 26.
Healthy aging is associated with declines in episodic memory. This reduction is thought to be due in part to age-related differences in encoding-related processes. In the current study, we performed an activation likelihood estimation meta-analysis of functional magnetic resonance imaging (fMRI) studies assessing age-related differences in the neural correlates of episodic encoding. Only studies using the subsequent memory paradigm were included. We found age-related under-recruitment of occipital and fusiform cortex, but over-recruitment in a set of regions including bilateral middle/superior frontal gyri, anterior medial frontal gyrus, precuneus and left inferior parietal lobe. We demonstrate that all of the regions consistently over-recruited by older adults during successful encoding exhibit either direct overlap, or occur in close vicinity to regions consistently involved in unsuccessful encoding in young adults. We discuss the possibility that this overall pattern of age-related differences represents an age-related shift in focus: away from perceptual details, and toward evaluative and personal thoughts and feelings during memory tasks. We discuss whether these age-related differences in brain activation benefit performance in older adults, and additional considerations.
健康衰老与情景记忆衰退相关。这种衰退部分被认为是由于与编码相关过程中与年龄相关的差异所致。在当前研究中，我们对功能磁共振成像（fMRI）研究进行了激活可能性估计元分析，这些研究评估了情景编码神经关联中与年龄相关的差异。仅纳入了使用后续记忆范式的研究。我们发现枕叶和梭状回与年龄相关的招募不足，但在包括双侧中/额上回、额内侧前回、楔前叶和左侧顶下叶在内的一组区域存在招募过度。我们证明，在成功编码过程中老年人始终过度招募的所有区域，要么直接重叠，要么紧邻年轻人中始终参与不成功编码的区域。我们讨论了这种与年龄相关差异的总体模式代表着一种与年龄相关的关注点转移的可能性：在记忆任务中，从感知细节转向评价性及个人的想法和感受。我们讨论了这些与年龄相关的大脑激活差异是否对老年人的表现有益，以及其他需要考虑的因素。
