中文摘要：

大脑老化会影响脑区之间的功能连接（FC）,近几年有研究表明脑区之间的功能连接是随着时间变化的,而这种动态的变化能反映更多的生理病理信息。因此,本研究基于静息态功能磁共振成像（fMRI）,采用滑动窗技术构建了32名老年受试者和36名年轻受试者的动态功能连接网络。利用小波包分析研究了波动能量差异对频段的依赖性,并与年龄进行线性回归分析。本文研究结果发现,老年组的功能连接波动能量在低频段高于青年组,而在高频段低于青年组。结果表明,老年人网络间的动态功能连接存在慢波化现象,这可能与老年人大脑的功能衰退有关。通过本文研究结果,可为脑老化的研究提供一种新的思路,同时也可促进对动态功能连接的理解。

英文摘要：

Brain aging can affect the strength of functional connectivity between brain regions. In recent years, studies have shown that functional connectivity is fluctuant over time, and can reflect more physiological and pathological information. Therefore, in the study resting state functional magnetic resonance imaging （fMRI） data of 32 elderly subjects and 36 younger subjects were selected, and the sliding window technique was used to estimate dynamic functional connectivity network. Then, the dependency of fluctuating energy difference on frequency band was studied using wavelet packet analysis, conducting the linear regression with age at the same time. Results showed that the fluctuating energy in older group was significantly higher than that in the young group in low frequency, and it was significantly lower than that in the young people in high frequency. These results suggested that the dynamic functional connectivity between networks in the elderly exist slow wave phenomenon, which may be related to the decreased reaction rate of the elderly. This article provides new ideas and methods for the research about brain aging, and promotes a theoretical basis for further understanding of the physiological significance of brain dynamic functional connectivity.