Brain function and structure in bipolar euthymia

描述（由申请人提供）：本提案的目的是评估诊断为I型双相情感障碍（躁狂发作史）且目前心境良好的患者的大脑结构和功能异常。患者和健康志愿者将接受结构和功能磁共振成像。功能性成像将在执行神经心理学任务时进行，该任务已知会激活腹侧前额叶皮层和杏仁核，这是情绪调节系统的已知组成部分。先进的基于表面的处理算法将用于高分辨率结构图像，以测量额叶皮层和其他大脑区域的灰质厚度。然后将使用相关分析来评估沿皮质每一点的皮质厚度和fMR信号强度之间的关系。由于腹侧额叶皮质区直接向杏仁核发送抑制投射，因此腹侧前额叶皮质变薄与杏仁核反应水平之间的关系也将被研究。这些研究首次尝试表征双相情感障碍患者额叶皮质的厚度，以及该区域的结构异常如何影响额边缘情绪调节回路的功能。实验结果将有助于提高我们对双相情感障碍病理生理学的理解，并识别使个体易患极端情绪的表现型大脑异常。未来的研究将检查这些大脑异常的出现和进展以及药物和治疗的相关影响，这将对患者的预后产生深远的影响。

DESCRIPTION (provided by applicant): The goal of this proposal is to assess abnormalities in brain structure and function in patients diagnosed with type I bipolar disorder (history of manic episode) who are currently euthymic. Patients and healthy volunteers will undergo structural and functional magnetic resonance imaging. Functional imaging will take place during the performance of a neuropsychological task known to activate ventral prefrontal cortex and amygdala, known components of the emotion regulatory system. Advanced surface based processing algorithms will be used on high resolution structural images to measure gray matter thickness in frontal cortex and other brain regions. A correlation analysis will then be used to assess, at every point along the cortex, the relationship between cortical thickness and fMR signal intensity. Because ventral frontal regions of cortex send direct inhibitory projections to the amygdala, the relationship between ventral prefrontal cortical thinning and the response level of the amygdala will also be examined. These studies represent the first attempt at characterizing the thickness of the frontal cortex in bipolar disorder and how structural abnormalities in this region impact functioning of fronto-limbic mood regulatory circuits. Results from the proposed experiments will help to advance our understanding of the pathophysiology of bipolar disorder and identify phenotypic brain abnormalities that predispose an individual to extreme liabilities in mood. Future studies that examine the emergence and progression of these brain abnormalities and the associated impact of medications and treatments will serve to have profound prognostic consequences for patients.