Brain Structure Predictors of Substance Use in Adolescence

描述（由申请人提供）：神经影像学研究已经确定了整个青春期和成年早期正在进行的神经组织发育。髓鞘和白质（WM）完整性的增加以及灰质（GM）皮质厚度的减少（例如，修剪）被认为可以加强突触连接，并允许大脑区域之间的有效交流。青少年参与药物使用行为的风险增加，而有问题的药物使用通常在这个发育时期开始达到顶峰。在青少年人群中，WM微结构完整性和GM皮质厚度之间的关系才刚刚开始被探索，横断面研究显示药物滥用与宏观结构和微结构神经组织状态之间的关系。研究表明，青少年冒险行为有很大的神经生物学成分，然而，冒险行为的生物学基础之间的联系还没有明确定义。WM完整性指数和GM皮质厚度指数结合使用可能有助于我们理解两种常用的结构成像测量的预测有效性，特别是它们在预测未来青少年物质使用方面的效用。因此，本研究将利用弥散张量成像（DTI）和结构磁共振成像（sMRI）来研究WM完整性和GM皮质厚度对现实世界风险行为（如吸毒和酗酒）的影响，测量间隔为36个月的16-18岁青少年基线。如果WM完整性和GM皮质厚度作为物质使用行为的预测因素存在经验支持，这些措施可以用来帮助识别有物质使用障碍风险的青少年。

DESCRIPTION (provided by applicant): Neuroimaging studies have identified ongoing neural tissue development throughout adolescence and early adulthood. Increases in myelination and white matter (WM) integrity along with decreases in gray matter (GM) cortical thickness (e.g., pruning) are thought to strengthen synaptic connections and allow for efficient communication between brain regions. Adolescents are at increased risk for engaging in substance use behaviors, and problematic use often begins to peak during this developmental time period. The relationship between WM microstructural integrity and GM cortical thickness is only beginning to be explored in adolescent populations, with cross sectional studies showing relationships between substance misuse and both macrostructural and microstructural neural tissue status. Research has shown a large neurobiological component to risk taking behaviors during adolescence, however the link between the biological underpinnings of risky behaviors has not been clearly defined. It is possible that indices of WM integrity and GM cortical thickness used in conjunction will help us understand the predictive validity of two commonly used structural imaging measurements, particularly their utility in predicting future adolescent substance use. Therefore, this study will utilize diffusion tensor imaging (DTI) and structural magnetic resonance imaging (sMRI) to examine the influence of WM integrity and GM cortical thickness on real world risk taking behaviors such as drug and alcohol use, measured over a 36-month interval in adolescents ages 16-18 at baseline. If empirical support exists for WM integrity and GM cortical thickness as predictors of substance use behaviors, these measures may be used to help identify teens at risk for substance use disorders.