Schey Center for Cognitive Neuroimaging, Neurological Institute, Cleveland Clinic, Cleveland, OH 44195, USA.
Curr Alzheimer Res. 2012 May;9(4):436-46. doi: 10.2174/156720512800492477.
Engagement in cognitively stimulating activities (CA) and leisure time physical activity (PA) have been associated with maintaining cognitive performance and reducing the likelihood of cognitive decline in older adults. However, neural mechanisms underlying protective effects of these lifestyle behaviors are largely unknown. In the current study, we investigated the effect of self-reported PA and CA on hippocampal volume and semantic processing activation during a fame discrimination task, as measured by functional magnetic resonance imaging (fMRI). We also examined whether possession of the apolipoprotein E (APOE) ε4 allele could moderate the effect of PA or CA on hippocampal structure or function.
Seventy-eight healthy, cognitively intact older adults underwent baseline neuropsychological assessment, hippocampal volume measurement via manually-traced structural MRI, and task-activated fMRI.
After 18 months, 27 participants declined by one standard deviation or more on follow-up neuropsychological testing. Logistic regression analyses revealed that CA alone or in combination with baseline hippocampal structure or functional activity did not predict the probability of cognitive decline. In contrast, PA interacted with APOE 4 status such that engagement in PA reduced the risk of cognitive decline in APOE 4 carriers only. Furthermore, the benefits of PA appeared to diminish with reduced functional activity or volume in the hippocampus.
Our findings suggest that increased leisure time PA is associated with reduced probability of cognitive decline in persons who are at high risk for AD. The beneficial effects of PA in this group may be related to enhancement of the functional and structural integrity of the hippocampus.
参与认知刺激活动（CA）和休闲时间体育活动（PA）与保持认知表现和降低老年人认知能力下降的可能性有关。然而，这些生活方式行为的保护作用的神经机制在很大程度上是未知的。在目前的研究中，我们通过功能磁共振成像（fMRI）测量，研究了自我报告的 PA 和 CA 对海马体积和语义处理激活的影响，在名人识别任务中。我们还检查了载脂蛋白 E（APOE）ε4 等位基因的存在是否可以调节 PA 或 CA 对海马结构或功能的影响。
78 名健康、认知健全的老年人接受了基线神经心理学评估、通过手动追踪结构 MRI 进行的海马体积测量以及任务激活 fMRI。
18 个月后，27 名参与者在随访神经心理学测试中下降了一个标准差或更多。逻辑回归分析表明，CA 单独或与基线海马结构或功能活动结合使用并不能预测认知下降的概率。相比之下，PA 与 APOE 4 状态相互作用，仅在 APOE 4 携带者中，PA 的参与降低了认知下降的风险。此外，PA 的益处似乎随着海马体功能活动或体积的减少而减少。
我们的研究结果表明，休闲时间 PA 的增加与 AD 高危人群认知下降的可能性降低有关。PA 在该组中的有益作用可能与增强海马体的功能和结构完整性有关。
