Synchrony in neuromagnetic oscillations as an indicator for coordination of brain activity underlying cognitive processes

神经磁振荡的同步性作为认知过程中大脑活动协调的指标

• 批准号: 341562-2012
• 负责人: Ross, Bernhard
• 金额: $ 1.82万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2012
• 资助国家: 加拿大
• 起止时间: 2012-01-01 至 2013-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=506366
• 关键词: Synchrony; neuromagnetic; oscillations; indicator; coordination

Cognition involves multiple brain areas and coordination of activity between these areas for successful function. One hypothesis is that precise timing plays a crucial role for coordination. Previous work using recording of neural activity with electrodes in the animal brain suggested that the relations of neural oscillations at various rhythms indicate coordination between brain areas. In humans we record related neuromagnetic signals noninvasively outside of the head with magnetoencephalography (MEG). Using mathematical methods for solving the 'inverse problem', we can estimate the brain activity generated at sources within the cortex. In this research program we are studying the synchrony between brain activity in two or more distant cortical sources. The inverse solution for source analysis may affect the observed synchrony measures. Therefore we will perform simulation studies to learn about the properties of our methods and to improve the sensitivity. In addition to synchrony of oscillations with the same rhythm another important principle is that brain rhythm at different frequencies interact with each other. It has been found that during a memory task, high frequency oscillations in the hippocampus occurred specifically at a certain phase of low frequency oscillations. We will develop new signal processing methods for detecting such interactions and coordinations between brain activities at different rhythms. We will apply the new brain research methods for studying how cognitive function changes with aging. One goal is to predict diseases like Alzheimer's at earliest stage in order to delay the onset of the disease through early intervention. We will use our brain imaging methods for monitoring the outcome of rehabilitation training. This is important for improving the rehabilitation programs. Behavioural measures are often not sensitive enough for differentiating between true learning effects and compensatory mechanisms. Moreover we will learn more about the role of brain oscillations for cognitive processes.

认知涉及多个大脑区域以及这些区域之间的活动协调以实现成功的功能。一种假设是，精确的时机对于协调起着至关重要的作用。先前使用动物大脑中的电极记录神经活动的研究表明，不同节律的神经振荡关系表明大脑区域之间的协调。在人类中，我们使用脑磁图 (MEG) 在头部外无创地记录相关的神经磁信号。使用数学方法解决“反问题”，我们可以估计皮层内源产生的大脑活动。在这个研究项目中，我们正在研究两个或多个遥远皮层源的大脑活动之间的同步性。源分析的逆解可能会影响观察到的同步测量。因此，我们将进行模拟研究，以了解我们方法的特性并提高灵敏度。除了具有相同节律的振荡同步之外，另一个重要原理是不同频率的大脑节律彼此相互作用。研究发现，在记忆任务中，海马区的高频振荡专门发生在低频振荡的某个阶段。我们将开发新的信号处理方法来检测不同节奏的大脑活动之间的相互作用和协调。我们将应用新的大脑研究方法来研究认知功能如何随着衰老而变化。目标之一是尽早预测阿尔茨海默氏症等疾病，以便通过早期干预延缓疾病的发作。我们将使用我们的大脑成像方法来监测康复训练的结果。这对于改善康复计划非常重要。行为测量通常不够敏感，无法区分真正的学习效果和补偿机制。此外，我们将更多地了解大脑振荡在认知过程中的作用。