ITR: High-Resolution Cortical Imaging of Brain Electrical Activity

过去的十年被称为“大脑的十年”，在过去的十年里，观察和测量人类大脑活动的能力出现了爆炸性的增长。功能磁共振成像(FMRI)技术能够对大脑结构进行精确的解剖定位，这些结构在某些心理过程中被激活。虽然fMRI具有很高的空间分辨率，但时间分辨率只有一秒左右。相比之下，电生理(脑电型)记录可以从头皮获得，并测量同步激活的神经元群的电活动(事件相关电位(ERP)提供毫秒级的时间分辨率，但空间分辨率有限。人们已经做出了巨大的努力来定位大脑中的电源生成器，这些电源生成器是由特定的感觉、运动或认知事件引起的ERP组件的基础。这种方法被称为电生理神经成像，试图通过去卷积体积传导过程，从头皮上获得的电生理记录中成像脑内神经源的分布。这一建议的重点是通过数学组合MRI和EEG数据来实现脑成像的高空间和时间分辨率。该方法涉及将从一种成像模式导出的约束放置在另一种模式的可能的逆解上。一旦算法被开发出来，这种方法将被应用于对大脑结构进行更精细的定位，这些结构涉及检测和响应认知任务中的错误。多模式脑成像技术将在研究健康受试者的执行控制系统和选定的精神分裂症患者组的执行功能障碍方面进行适用性和性能评估。

0218736HeThe past decade, dubbed the "Decade of the Brain", has witnessed explosive growth in the ability to observe and measure brain activity in human subjects. The technique of functional magnetic resonance imaging (fMRI) has enabled precise anatomical localization of brain structures that are activated during certain psychological processes. Though fMRI has high spatial resolution, temporal resolution is on the order of a second. In contrast, electrophysiological (EEG type) recordings, which can be obtained from the scalp and measure the electrical activity of ensembles of neurons activated synchronously (event-related potentials (ERP) provide millisecond level temporal resolution but limited spatial resolution. Tremendous efforts have been made to localize electrical source generators within the brain that underlie ERP components evoked by specific sensory, motor, or cognitive events. The approach, called electrophysiological neuroimaing, attempts to image the neural source distribution within the brain from electophysiological recordings obtained over the scalp by deconvolving the volume conduction process. The focus of this proposal is to achieve high spatial and temporal resolution in brain imaging by mathematically combining MRI and EEG data. The method involves placing constraints derived from one imaging modality on possible inverse solutions of the other modality. Once the algorithms are developed, the method will be applied to obtaining finer localization of brain structures involved in detecting and responding to an error in a cognitive task. The multimodal brain imaging technique will be assessed for applicability and performance in studying executive control systems in healthy subjects and disturbance of executive functions in selected groups of patients with schizophrenia.