ITR: High-Resolution Cortical Imaging of Brain Electrical Activity

0218736He过去的十年被称为“大脑的十年”，见证了观察和测量人类受试者大脑活动能力的爆炸性增长。 功能性磁共振成像（fMRI）技术已经能够对在某些心理过程中激活的大脑结构进行精确的解剖定位。 虽然功能磁共振成像具有很高的空间分辨率，时间分辨率是一秒的数量级。 相比之下，可以从头皮获得并测量同步激活的神经元集合的电活动（事件相关电位（ERP））的电生理（EEG类型）记录提供毫秒级的时间分辨率，但空间分辨率有限。 已经做出了巨大的努力，以本地化的电源发生器在大脑中的ERP组件引起的特定的感觉，运动，或认知事件。 这种方法被称为电生理神经成像，试图通过对体积传导过程进行去卷积，从头皮上获得的电生理记录中对大脑内的神经源分布进行成像。 该建议的重点是通过数学结合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态导出的约束放置在另一种模态的可能的逆解上。 一旦算法被开发出来，该方法将被应用于获得涉及检测和响应认知任务中错误的大脑结构的更精细定位。 将评估多模态脑成像技术在研究健康受试者的执行控制系统和选定精神分裂症患者组的执行功能障碍中的适用性和性能。

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.