Inferring Cortical Feed-Forward and Feedback Processes with Human Neuroimaging

利用人类神经影像推断皮质前馈和反馈过程

• 批准号: 7454312
• 负责人: SEPPO PENTTI AHLFORS
• 金额: $ 42.43万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-07-01 至 2010-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7454312
• 关键词: Address; Area; Brain; Cerebral cortex; Characteristics; Cognitive; Communication; Computer Simulation; Computer information processing; Contralateral; Data; Disease; Electroencephalography; Evaluation; Feedback; Fusiform gyrus; Human; Image; Invasive; Ipsilateral; Lead; Magnetoencephalography; Measures; Modeling; Monkeys; Nature; Pattern; Primates; Process; Property; Research; Research Personnel; Resolution; Solutions; Somatosensory Cortex; Source; Stimulus; Structure; Synapses; Testing; Time; Visual; base; cognitive function; cognitive neuroscience; feeding; insight; median nerve; neuroimaging; neuromechanism; novel; object perception; object recognition; relating to nervous system; response; somatosensory; spatiotemporal; theories; white matter

DESCRIPTION (provided by applicant): A central question related to information flow in the human brain is: how do bottom-up and top-down influences interact in the cerebral cortex? A hypothesis is proposed that could form the basis for a novel way to use non-invasive neuroimaging to address this question. Specifically, the direction of the current dipoles detected by magneto- and electroencephalography (MEG, EEG) is expected to be a function of whether the measured activation is a result of top-down (feedback) or bottom-up (feed-forward) flow in the cortex. This hypothesis is founded on the principle that feed-forward and feedback connections into a cortical area have characteristic laminar pattern of synaptic inputs. Consequently, knowing which of the cortical layers received a certain input could be highly informative about the source of this input, and more generally about inter- cortical communication. Such insights about the laminar structure are beyond the resolution of human neuroimaging. However, the proposal that the different types of laminar inputs might result in macroscopic dipoles with different polarities has the potential to provide a powerful non-invasive solution. The overall hypothesis is evaluated using three different approaches: biophysically realistic computational modeling (Aim 1), comparison of somatosensory MEG/EEG responses with intracranial primate recordings (Aim 2), and evaluation of experimental predictions about the polarity of MEG/EEG sources derived from a cognitive neuroscience theory of visual object perception (Aim 3). This research is anticipated to enable non-invasive inference of information flow in networks of cortical areas. It will provide a novel way to apply MEG/EEG recordings to studies of cognitive processing and interpret MEG/EEG in the context of large-scale integrative theories of the brain. It could lead to a better understanding of the neural mechanisms underlying cognitive functions, as well as to potential applications for revealing mechanisms of neural disorders.

描述（由申请人提供）：与人脑信息流相关的一个中心问题是：自下而上和自上而下的影响如何在大脑皮层中相互作用？提出的假设可以为使用非侵入性神经影像来解决这个问题的新方法奠定基础。具体来说，通过脑磁图和脑电图（MEG、EEG）检测到的电流偶极子的方向预计是测量的激活是自上而下（反馈）还是自下而上（前馈）流动的结果的函数在皮质中。该假设基于这样的原理：皮质区域的前馈和反馈连接具有突触输入的特征层状模式。因此，了解哪个皮质层接收到特定的输入可以提供有关该输入来源的大量信息，并且更广泛地了解皮质间通信。这种关于层状结构的见解超出了人类神经成像的分辨率。然而，不同类型的层流输入可能导致具有不同极性的宏观偶极子的提议有可能提供强大的非侵入性解决方案。使用三种不同的方法评估总体假设：生物物理现实计算模型（目标 1）、体感 MEG/EEG 响应与颅内灵长类动物记录的比较（目标 2）以及对来自以下来源的 MEG/EEG 源极性的实验预测的评估视觉对象感知的认知神经科学理论（目标 3）。这项研究预计将能够对皮质区域网络中的信息流进行非侵入性推断。它将提供一种新颖的方法，将 MEG/EEG 记录应用于认知处理研究，并在大脑大规模综合理论的背景下解释 MEG/EEG。它可以使人们更好地理解认知功能背后的神经机制，以及揭示神经疾病机制的潜在应用。