Yao Zhijun, Liao Mei, Hu Tao, Zhang Zhe, Zhao Yu, Zheng Fang, Gutknecht Jürg, Majoe Dennis, Hu Bin, Li Lingjiang
Key Laboratory of Wearable Computing of Gansu Province, Lanzhou University, Lanzhou, China.
Mental Health Institute, The Second Xiangya Hospital of Central South University, Changsha, China.
Front Hum Neurosci. 2017 Oct 13;11:492. doi: 10.3389/fnhum.2017.00492. eCollection 2017.
Generalized anxiety disorder (GAD) is one of common anxiety disorders in adolescents. Although adolescents with GAD are thought to be at high risk for other mental diseases, the disease-specific alterations have not been adequately explored. Recent studies have revealed the abnormal functional connectivity (FC) in adolescents with GAD. Most previous researches have investigated the static FC which ignores the fluctuations of FC over time and focused on the structures of "fear circuit". To figure out the alterations of dynamic FC caused by GAD and the possibilities of dynamic FC as biomarkers, we propose an effective approach to identify adolescent GAD using temporal features derived from dynamic FC. In our study, the instantaneous synchronization of pairwise signals was estimated as dynamic FC. The Hurst exponent (H) and variance, indicating regularity and variable degree of a time series respectively, were calculated as temporal features of dynamic FC. By leave-one-out cross-validation (LOOCV), a relatively high accuracy of 88.46% could be achieved when H and variance of dynamic FC were combined as features. In addition, we identified the disease-related regions, including regions belonging to default mode (DM) and cerebellar networks. The results suggest that temporal features of dynamic FC could achieve a clinically acceptable diagnostic power and serve as biomarkers of adolescent GAD. Furthermore, our work could be helpful in understanding the pathophysiological mechanism of adolescent GAD.
广泛性焦虑症（GAD）是青少年常见的焦虑症之一。尽管患有GAD的青少年被认为有患其他精神疾病的高风险，但针对该疾病的特异性改变尚未得到充分研究。最近的研究揭示了患有GAD的青少年存在异常的功能连接（FC）。此前大多数研究都调查了静态FC，这种方法忽略了FC随时间的波动，并且聚焦于“恐惧回路”的结构。为了弄清楚GAD导致的动态FC改变以及动态FC作为生物标志物的可能性，我们提出了一种利用从动态FC中提取的时间特征来识别青少年GAD的有效方法。在我们的研究中，将成对信号的瞬时同步估计为动态FC。分别作为动态FC时间特征计算的赫斯特指数（H）和方差，分别表示时间序列的规律性和可变程度。通过留一法交叉验证（LOOCV），当将动态FC的H和方差作为特征结合使用时，可以达到相对较高的88.46%的准确率。此外，我们确定了与疾病相关的区域，包括属于默认模式（DM）和小脑网络的区域。结果表明，动态FC的时间特征可以达到临床上可接受的诊断能力，并作为青少年GAD的生物标志物。此外，我们的工作可能有助于理解青少年GAD的病理生理机制。
