Integrating EEG/MEG and fMRI: 99-M-0172

脑磁图数据记录和信号处理方法的发展已经非常成功。对工作记忆任务和听觉处理任务的研究已经显示了定位大脑激活和解决阶段性与紧张性活动问题的能力。我们正在调查表型的措施，将适用于许多相关的研究，特别是同胞项目。 认知激活过程中的脑磁图记录显示出与功能磁共振成像非常相似的定位能力。特别是皮质水平的β去磷酸化与BOLD激活结果一致。然而，MEG/EEG允许使用其他成像技术不可能的时间信息。跨大脑区域的相位关系已经使用先进的信号处理技术得到了证明。我们的研究结果表明，大脑结构和功能的措施是找到易感基因的有力工具。进一步的研究已经证明了定位信号在更深的结构，如杏仁核的能力，并调查视觉意识的伽马波段信号的关系。我们还发现，GABA（γ-氨基丁酸）在前扣带皮层浓度与空间定位静息脑磁图β带功率。我们期望进一步的研究将揭示更多的γ功率和GABA系统之间的关系。 在工作记忆任务中，精神分裂症患者与健康的同胞和正常对照志愿者相比，其激活程度不同，特别是在额叶区域，这是由β去激活所指示的。对这种激活的进一步研究揭示了与已充分研究的COMT标记的基因型的相互作用。我们发现，在预期即将到来的任务需求时，前额叶皮层的活动会发生调制。这种预备信号在研究患者人群的认知功能障碍时可能很重要。 网络模式和动力学的差异是理解临床组中潜在病理学的关键。Bassett等人已经表明，患者群体中的功能网络差异可以被证明并与认知活动的行为结果相关。Rutter等人已经表明，即使在休息时，与正常受试者相比，精神分裂症患者的伽马功率也会降低。这些发现是否与状态或性状差异有关，以及是否存在遗传关联，还有待观察。我们发现，参与这些记忆任务的大脑区域的时间序列具有不同的模式，这些模式显示出受试者之间的各种个体差异。这些差异将形成基因型模式和患者群体中的区分的基础。

Development of MEG data recording and signal processing methods has been very successful. Studies of working memory tasks and auditory processing tasks have shown the ability to localize brain activation and to address issues of phasic versus tonic activity. We are investigating phenotype measures that will be applicable in many related studies and specifically the sibling project. MEG recording during cognitive activation has shown the ability to localize in very comparable fashion to fMRI. Specifically beta desynchronization at the cortical level has been found to agree with BOLD activation results. However, the MEG/EEG allows for temporal information not possible with other imaging techniques. Phasic relationships across brain areas have been demonstrated using advanced signal processing techniques. Our results show that measures of brain structure and function represent powerful tools to find susceptibility genes. Further studies have demonstrated the ability to localize signals in deeper structures such as the amygdala and to investigate the relation of visual awareness to gamma band signals. We have also found that GABA (gamma-aminobutyric acid) concentration in the anterior cingulate cortex correlates with spatially localized resting MEG beta band power. We expect that further investigation will reveal addtional relationships between gamma power and GABA systems. Diffrerences in the degree of activation especially in frontal regions as indexed by beta desynchronization during a working memory task have been found between patients with schizophrenia compared to well siblings and normal control volunteers. Further investigation of this activation has revealed an interaction with genotype for the well studied COMT marker. We have found there is a modulation of prefrontal cortex activity that occurs in anticipation of the upcoming task demands. This preparatory signal may be important in investigating cognitive dysfunction in patient populations. Differences in network patterns and dynamics are key to understanding underlying pathology in clinical groups. Bassett et al have shown that functional network differences in patient groups can be demonstrated and related to behavioral outcomes on cognitive activities. Rutter et al have shown that even at rest patients with schizophrenia have gamma power reduction compared to normal subjects. It remains to be seen whether these finding relate to state or trait differences and if there are genetic associations. We have found distinct patterns of the temporal sequence of brain regions involved in these memory tasks that show a variety of individual differences across subjects. These differences will form the basis for genotypic patterns and dscrimination in patient groups.