NEURAL BASIS OF ENDOGENOUS POTENTIALS IN HUMANS

描述(改编自Aplicant的摘要)：人类的认知过程 可以以毫秒精度测量的一系列步长，如 内源性脑电和脑磁图 菲尔兹。脑磁图/脑电图是功能性磁共振成像的补充 (FMRI)，因为fMRI提供了大脑激活的直接定位 认知能力差，但时间分辨率低。仅限脑内脑电(IEEG) 记录可以证明局部生成具有很高的时空精度。 然而，iEEG受到可能的病理污染和 抽样不完全。 拟议的研究试图以高度的时间和空间来定位 通过在精确的计算中结合上述技术来提高精确度 大脑及其周围环境的生物物理模型。首先，激活将 使用功能磁共振成像在正常受试者的整个大脑中定位 定位、人脸、物体和单词感知、远程语义记忆 句法分析、最近的陈述性记忆和初级记忆。第二, 在同一时间内，将记录相同受试者的全头脑磁图/脑电 任务，在简单的任务中唤起N2、P3a、P3b和Sw，此外 在使用语义刺激的任务中，P170、N310、N400和CNV。第三， 位于该区域的皮质偶极子激活的时程 由fMRI确定的最符合EEG/MEG数据的数据将被找到。 最后，这些假想的时间进程将用iEEG记录进行测试 直接从上述研究中发现的地点获得 使用fMRI激活，在激活每个站点的任务期间，使用 癫痫患者的脑内电极。假设 视觉相关特定脑区的激活时程 在之前的fMRI/MEG研究中获得的运动和注意力也将 测试过。所有脑叶的跨受试者皮质和边缘区域 已采样。对象内验证将在有限的数量中实现 在相同的认知任务中接受fMRI/MEG/iEEG/EEG记录的患者。 这些患者手术前后的fMRI/EEG将被记录下来 切除发电机区域，以测试改变的传播是否会 观察了模型预测的头皮，并针对可能的损失 调制效应。 拟议的研究将允许对大脑活动的不同观点 FMRI、EEG、MEG和iEEG要单独和一起进行比较，领先 可能是为了更好地了解它们的相对优势，以及 完善它们的融合技术。此外，建议的 研究将加深我们对大脑活动模式的了解 感知、记忆和语言，是迈向最终目标的重要一步 认知功能神经模型的构建。最后，更多 关于认知潜能产生的完整知识应该是 大大提高了它们作为特定大脑系统功能测试的价值 在患有神经或精神疾病的患者中。

DESCRIPTION (Adapted from Aplicant's Abstract): Human cognition proceeds by a series of steps that can be measured with millisecond accuracy as endogenous electroencephalographic (EEG) and magnetoencephalographic (MEG) fields. MEG/EEG are complementary to functional magnetic resonance imaging (fMRI), in that fMRI provides direct localization of brain activation during cognition, but with poor temporal resolution. Only intracerebral EEG (iEEG) recordings can prove local generation with high spatiotemporal accuracy. However, iEEG is limited by possible pathological contamination and incomplete sampling. The proposed studies seek to localize with high temporal and spatial accuracy by combining the above techniques within an accurate computational biophysical model of the brain and its surroundings. First, activation will be localized in the entire brain of normal subjects using fMRI during orienting, face, object and word perception, remote semantic memory, syntactic analysis, recent declarative memory, and primary memory. Second, whole-head MEG/EEG will be recorded from the same subjects during the same tasks, evoking the N2, P3a, P3b, and SW in simple tasks, and additionally the P170, N310, N400, and CNV in tasks using semantic stimuli. Third, the time-course of activation of the cortical dipoles lying in the areas identified by fMRI, that best fits the EEG/MEG data, will be found. Finally, these hypothesized time-courses will be tested with iEEG recordings directly from the sites that have been found in the studies above to be activated with fMRI, during the tasks that activate each site, using intracerebral electrodes in patients with epilepsy. Hypothesized time-courses of activation in specific brain regions related to visual motion and attention obtained in previous fMRI/MEG studies will also be tested. Across-subjects, cortical and limbic areas in all lobes will be sampled. Within-subject validation will be possible in limited number of patients with fMRI/MEG/iEEG/EEG recordings during the same cognitive tasks. fMRI/EEG will be recorded from these same patients before and after surgical excision of generator areas, in order to test if the altered propagation to the scalp predicted by the model is observed, and for the possible loss of modulatory effects. The proposed studies will allow the different views on brain activity from fMRI, EEG, MEG, and iEEG to be compared, singly and together, leading possibly to better understanding of their relative strengths, and the refinement of techniques for their integration. In addition, the proposed studies will deepen our knowledge of brain activity patterns during perception, memory and language, an essential step toward the eventual construction of functional neural models for cognition. Finally, more complete knowledge regarding the generators of cognitive potentials should greatly increase their value as functional tests for specific brain systems in patients with neurological or psychiatric disease.