Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania.
Department of Psychology, Carnegie Mellon University, Pittsburgh, Pennsylvania.
Hippocampus. 2018 Mar;28(3):239-247. doi: 10.1002/hipo.22827. Epub 2018 Jan 27.
Consistent associations have been found between higher cardiorespiratory fitness (CRF) and indices of enhanced brain health and function, including behavioral measures of cognition as well as neuroimaging indicators such as regional brain volume. Several studies have reported that higher CRF levels are associated with a larger hippocampus, yet associations between volume and memory or functional connectivity metrics remain poorly understood. Using a multi-modal framework, we hierarchically examine the association between CRF and hippocampal volume and resting state functional connectivity (rsFC) in younger adults, as well as their relationship between with memory function. We conducted theoretically-driven analyses with seeds in the anterior and posterior hippocampus, as well as control seeds in the caudate nucleus. We tested whether (1) hippocampal connectivity with prefrontal cortical regions was associated with CRF in an adult sample much younger than traditionally tested, (2) associations between CRF and rsFC remain significant after adjusting for volume, and (3) volume and rsFC are related to memory. We found that higher CRF levels were associated with larger anterior hippocampal volume and more positive rsFC of the anterior hippocampus to several regions including the prefrontal cortex. rsFC also accounted for significant variance in CRF, above and beyond volume. CRF can thus be independently linked to increased anterior hippocampal volume, as well as stronger hippocampal rsFC in a population much younger than those typically tested, suggesitng it is critical to maintainig multiple aspects of brain health.
一直以来，较高的心肺适能（cardiorespiratory fitness，CRF）与增强的大脑健康和功能指数之间存在关联，包括认知行为测量以及区域脑容量等神经影像学指标。有几项研究报告称，较高的 CRF 水平与更大的海马体有关，但体积与记忆或功能连接度指标之间的关联仍知之甚少。本研究采用多模态框架，在年轻成年人中分层检查 CRF 与海马体体积和静息状态功能连接（resting state functional connectivity，rsFC）之间的关联，以及它们与记忆功能之间的关系。我们在前海马体和后海马体以及尾状核中使用理论驱动的种子进行了分析。我们检验了以下几点：（1）在比传统测试年轻得多的成年样本中，海马体与前额皮质区域的连接是否与 CRF 相关；（2）在调整体积后，CRF 与 rsFC 之间的关联是否仍然显著；（3）体积和 rsFC 与记忆相关。结果发现，较高的 CRF 水平与较大的前海马体体积和前海马体与包括前额皮质在内的多个区域的更积极的 rsFC 相关。rsFC 还解释了 CRF 中的显著方差，超过了体积的解释。因此，CRF 可以独立地与前海马体体积增加以及海马体 rsFC 增强相关联，这在比传统测试年轻得多的人群中表明，维持大脑健康的多个方面至关重要。
