中文摘要：

在缺省模式网络(DMN ) 放松状态的年龄相关的变化可以提供新线索给一些 neuropsychiatric 混乱的正常大脑以及早诊断和治疗的发展中的机制。到信号最近提起了增加注意的功能的磁性的回声成像(fMRI ) 的 multifractal 理论的应用程序。我们试图探索位于休息状态下面的 multifractal 特征从 DMN 提取的功能的磁性的回声成像(rs-fMRI ) 系列，和二个问题主要被讨论：(1 ) 是否在那里存在在 rs-fMRI 的 multifractals 系列；(2 ) 借助于 multifractal 特征在不同年龄或性之间区分是否是可能的。结果在 DMN 在 rs-fMRI 系列表明了 multifractals 的存在。另外，年轻题目之间的细微差别和中年或老的题目能是成功地由 \ 检测了(\Delta_{\text { 作为 }}\alpha \) ，我们建议了的一项修改措施。而且，从年轻题目的 rs-fMRI 系列拥有更小的平均规模索引和更弱的长期的关联，这被揭示，当那些从中年或老的在场的人增加平均规模索引和更强壮的长期的关联时。而没有重要统计差别在男、女的组之间被发现了。因此，我们的结果在某个大脑区域的 fMRI 系列加亮 multifractal 分析的潜在的实用性，并且在 DMN 提供重要卓见进健康老化。

英文摘要：

Age-related changes of resting state in default mode network （DMN） may provide new clues to the developing mechanism of normal brain as well as early diagnosis and therapy of some neuropsychiatric disorders. The application of multifractal theory to functional magnetic resonance imaging （fMRI） signals has recently raised increasing attention. We aim to explore the multifractal characteristics underlying the resting state functional magnetic resonance imaging （rs-fMRI） series extracted from DMN, and two issues are mainly discussed： （1） whether there exist multifractals in rs-fMRI series; （2） whether it is possible to distinguish between the different ages or genders by means of multifractal characteristics. Results demon- strated the existence of multifractals in rs-fMRI series in DMN. In addition, slight differences between young subjects and middle-aged or elderly subjects can be successfully detected by △asα, a modified measure we proposed. Furthermore, it is revealed that the rs-fMRI series from young subjects possess smaller averaged scale index and weaker long range correlation, while those from middle-aged or elderly people present increasing averaged scale index andstronger long range correlation. Whereas no significant statistical differences has been found between male and female group. Our results, therefore, highlight the potential useful- ness of multifractal analysis in fMRI series of a certain brain region, and provide important insights into healthy aging in DMN.