Non-invasive laminar electrophysiology in humans

人体非侵入性层状电生理学

• 批准号: BB/M009645/1
• 负责人: Gareth Barnes
• 金额: $ 44.08万
• 依托单位: University College London
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2015
• 资助国家: 英国
• 起止时间: 2015 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FM009645%2F1
• 关键词: Non; invasive; laminar; electrophysiology; humans

Through experience we learn what to expect from the world around us. We become familiar with particular sensory information and we use this previous experience to make predictions about what we expect to see or touch. When the sensory information is not as we expected, this information (or prediction error) is fed forward to correct future predictions. For example it may be that you have had the impression that your stationary train is leaving the station simply because another train moves alongside you. This is an example of visual information making a prediction about the state of the world- which in this case happens to be a prediction error. We know from the anatomy of the cortex that the pathways that carry this feedback (predictions) and feedforward (prediction errors) information intertwine in parallel streams which interconnect brain regions that process very low level sensory information through multiple intermediate levels right up to those brain regions in which we make decisions about what to do. Interestingly, these pathways have distinct origins with feedforward and feedback pathways originating in the upper and lower cortical layers respectively (separated by around 3-4mm). Besides being distinguishable anatomically, these feedback and feedforward streams operate within distinct frequency ranges, the feedback signals changing more slowly (about 10-20 times a second) than the feedforward (about 30-60 times a second). At present the only way that we can look at these feedforward and feedback signals as they pass through the brain is through implanting micro-electrode arrays in the brains of animals. This is because the majority of human brain scanners either can see the layers but can only watch how they change over many seconds (functional Magnetic Resonance Imaging); or they distinguish the feedback and feedfoward signals in time but cannot resolve where they are coming from (electroencephalography or EEG). This grant builds on recent technological developments in magnetoencephalography (MEG) in which we measure magnetic fields outside the head produced by electrical currents flowing in the human brain. MEG, like EEG, can distinguish between these feedforward and feedback signals in time and frequency; importantly we have recently shown that it is also possible to distinguish between cortical layers using MEG. This is made possible because we have very precise models of where the different cortical layers lie with respect to our magnetic field measuring system (MEG). In this grant we put these two things together and expect to show that we can non-invasively disentangle feedback from feedforward information in both frequency (feedback low frequency, feedforward high frequency) and space (feedforward and feedback origins in upper and lower cortical layers respectively). This is a completely safe and non-invasive technique we can use in humans. Importantly, it will allow us to study how this feedforward and feedback information propagates across multiple areas of the human brain simultaneously - something that cannot even be done in invasive animal studies.This will not only help us understand how the brain works, but will help us understand what happens when these feedback and feedforward streams become compromised in conditions such as Parkinson's disease of schizophrenia.

通过经验，我们了解对周围世界的期望。我们熟悉特定的感官信息，并利用以前的经验来预测我们期望看到或触摸的内容。当感官信息不如我们预期的那样，该信息（或预测错误）会向前馈入以纠正未来的预测。例如，可能是因为您的静止火车仅仅是因为另一列火车与您一起移动，因此您的静止火车的印象是。这是视觉信息的一个示例，可以对世界状态进行预测 - 在这种情况下，这恰好是一个预测错误。从皮层的解剖结构中，我们知道，携带此反馈（预测）和前馈（预测错误）信息的途径在平行流中交织在一起，这些信息相互连接的大脑区域，这些区域通过在这些大脑区域进行多个中间水平处理非常较低的水平感觉信息，在其中我们做出决定。有趣的是，这些途径具有独特的起源，其前馈和反馈途径分别源于上层和下皮层层（分别为3-4mm左右）。除了解剖学上可区分的是，这些反馈和前馈流在不同的频率范围内运行外，反馈信号的变化速度比馈电（每秒大约30-60倍）更慢（大约每秒10-20倍）。目前，我们可以通过将微电极阵列植入动物的大脑时，可以看出这些前馈信号和反馈信号。这是因为大多数人脑扫描仪都可以看到这些层，但只能观察它们在许多秒内的变化（功能性磁共振成像）。或者，他们会及时区分反馈和饲料信号，但无法解决它们来自的位置（脑电图或脑电图）。这项赠款建立在磁脑电图（MEG）的最新技术发展上，在该技术发展中，我们测量了由人脑中流动的电流产生的头部外部的磁场。像脑电图一样，梅格可以在时间和频率上区分这些进料和反馈信号。重要的是，我们最近表明，也可以区分使用MEG的皮质层。之所以成为可能，是因为我们有非常精确的模型，即相对于我们的磁场测量系统（MEG），不同的皮质层位置。在这笔赠款中，我们将这两件事放在一起，并期望表明我们可以在频率（反馈低频，高频高频）和空间（分别在上层和下皮层层中的前进和反馈起源）中从频率（反馈低频率，馈电和反馈起源）中进行非侵入性解开反馈。这是我们可以在人类中使用的一种完全安全且无创的技术。重要的是，这将使我们能够同时研究这种前馈和反馈信息在人类大脑的多个领域中如何传播 - 甚至在侵入性动物研究中都无法做到这一点。这不仅可以帮助我们了解大脑的工作方式，而且还将帮助我们了解这些反馈和前进流在诸如帕克森氏病等条件下会损害的情况下会发生什么。

项目成果

Using optically-pumped magnetometers to measure magnetoencephalographic signals in the human cerebellum

使用光泵磁力计测量人类小脑中的脑磁信号

• DOI: 10.1101/425447
• 发表时间: 2018
• 作者: Lin C

Estimates of cortical column orientation improve MEG source inversion.

• DOI: 10.1016/j.neuroimage.2020.116862
• 发表时间: 2020-08-01
• 期刊: NeuroImage
• 影响因子: 5.7
• 作者: Bonaiuto JJ;Afdideh F;Ferez M;Wagstyl K;Mattout J;Bonnefond M;Barnes GR;Bestmann S
• 通讯作者: Bestmann S

Laminar dynamics of beta bursts in human motor cortex

人类运动皮层β爆发的层流动力学

• DOI: 10.1101/2021.02.16.431412
• 发表时间: 2021
• 作者: Bonaiuto J

A new generation of magnetoencephalography: Room temperature measurements using optically-pumped magnetometers.

• DOI: 10.1016/j.neuroimage.2017.01.034
• 发表时间: 2017-04-01
• 期刊: NeuroImage
• 影响因子: 5.7
• 作者: Boto E;Meyer SS;Shah V;Alem O;Knappe S;Kruger P;Fromhold TM;Lim M;Glover PM;Morris PG;Bowtell R;Barnes GR;Brookes MJ
• 通讯作者: Brookes MJ

Non-invasive laminar inference with MEG: Comparison of methods and source inversion algorithms.

• DOI: 10.1016/j.neuroimage.2017.11.068
• 发表时间: 2018-02-15
• 期刊: NeuroImage
• 影响因子: 5.7
• 作者: Bonaiuto JJ;Rossiter HE;Meyer SS;Adams N;Little S;Callaghan MF;Dick F;Bestmann S;Barnes GR
• 通讯作者: Barnes GR