EFFECTS OF UNCERTAINTY ON BOLD FMRI

本子项目是利用由NIH/NCRR资助的中心赠款提供的资源的众多研究子项目之一。子项目和研究者（PI）可能已经从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。列出的机构是中心的，不一定是研究者的机构。焦虑是一系列复杂的反应，包括高度的觉醒、肌肉和自主神经反应，以及注意力、学习和认知过程对潜在危险暗示的转变。焦虑反应的不同取决于威胁的严重程度、持续时间和复杂性。本研究的目的是利用功能磁共振成像（fMRI）检查无焦虑症的正常个体和广泛性焦虑症（GAD）患者的不确定性引起的焦虑的神经生物学。尽管fMRI研究已经使用经典条件反射范式进行，但在涉及行为后果不确定的任务期间，关于焦虑的数据有限。这项试点调查将使用行为表现测量、自我报告的焦虑和功能磁共振成像来检查偶然性不确定性的影响。特别是，不确定性可以通过改变惩罚相对于强化的概率，以及使用区别性刺激来指示偶然事件的变化来操纵。焦虑和非焦虑受试者之间的差异以及低不确定性和高不确定性条件之间的差异将被检验。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Anxiety is complex set of reactions that include heightened arousal, muscular and autonomic responses, and shifts in attention, learning, and cognitive processing to cues indicating potential danger. Anxiety responses differ depending on the severity of the threat, its duration, and complexity. The aim of the study is to examine the neurobiology of anxiety induced by uncertainty in normal individuals without anxiety disorders and in patients with generalized anxiety disorder (GAD) using fMRI. Although fMRI studies have been conducted using classical conditioning paradigms, there is limited data on anxiety during tasks that involve uncertainty about the consequences for behavior. This pilot investigation will examine the effects of contingency uncertainty using behavioral performance measures, self-reported anxiety, and fMRI. In particular, uncertainty will be manipulated by altering both the probability of punishment relative to reinforcement, as well as the use of discriminative stimuli to signal changes in contingencies. Differences between anxious and non-anxious subjects as well as differences between conditions with low versus high uncertainty will be examined.