Herreras O, Makarova J, Makarov V A
Department of Systems Neuroscience, Cajal Institute, CSIC, Avenida Doctor Arce 37, Madrid 28002, Spain.
Department of Applied Mathematics, School of Mathematics, University Complutense of Madrid, Plaza de Ciencias 3, Ciudad Universitaria, Madrid 28040, Spain.
Neuroscience. 2015 Dec 3;310:486-503. doi: 10.1016/j.neuroscience.2015.09.054. Epub 2015 Sep 28.
Local field potentials (LFPs) reflect the coordinated firing of functional neural assemblies during information coding and transfer across neural networks. As such, it was proposed that the extraordinary variety of cytoarchitectonic elements in the brain is responsible for the wide range of amplitudes and for the coverage of field potentials, which in most cases receive contributions from multiple pathways and populations. The influence of spatial factors overrides the bold interpretations of customary measurements, such as the amplitude and polarity, to the point that their cellular interpretation is one of the hardest tasks in Neurophysiology. Temporal patterns and frequency bands are not exclusive to pathways but rather, the spatial configuration of the voltage gradients created by each pathway is highly specific and may be used advantageously. Recent technical and analytical advances now make it possible to separate and then reconstruct activity for specific pathways. In this review, we discuss how spatial features specific to cells and populations define the amplitude and extension of LFPs, why they become virtually indecipherable when several pathways are co-activated, and then we present the recent advances regarding their disentanglement using spatial discrimination techniques. The pathway-specific threads of LFPs have a simple cellular interpretation, and the temporal fluctuations obtained can be applied to a variety of new experimental objectives and improve existing approaches. Among others, they facilitate the parallel readout of activity in several populations over multiple time scales correlating them with behavior. Also, they access information contained in irregular fluctuations, facilitating the testing of ongoing plasticity. In addition, they open the way to unravel the synaptic nature of rhythmic oscillations, as well as the dynamic relationships between multiple oscillatory activities. The challenge of understanding which waves belong to which populations, and the pathways that provoke them, may soon be overcome.
局部场电位（LFPs）反映了在神经网络中信息编码和传递过程中功能性神经组件的协同放电。因此，有人提出，大脑中细胞构筑元素的非凡多样性导致了场电位幅度范围广泛以及覆盖范围广，在大多数情况下，场电位会受到多种通路和神经元群体的影响。空间因素的影响超越了对常规测量（如幅度和极性）的大胆解读，以至于对其进行细胞层面的解读成为神经生理学中最艰巨的任务之一。时间模式和频段并非特定通路所独有，相反，每条通路产生的电压梯度的空间配置是高度特异性的，并且可以得到有效利用。最近的技术和分析进展使得分离并重建特定通路的活动成为可能。在本综述中，我们讨论细胞和神经元群体特有的空间特征如何定义局部场电位的幅度和范围，为何当多条通路共同激活时它们几乎变得难以解读，然后我们介绍利用空间辨别技术对其进行解缠的最新进展。局部场电位的通路特异性线索具有简单的细胞层面解释，所获得的时间波动可应用于各种新的实验目标并改进现有方法。其中，它们有助于在多个时间尺度上并行读取多个神经元群体的活动，并将其与行为相关联。此外，它们能够获取不规则波动中包含的信息，便于对正在进行的可塑性进行测试。此外，它们为揭示节律性振荡的突触本质以及多种振荡活动之间的动态关系开辟了道路。理解哪些波属于哪些神经元群体以及引发它们的通路这一挑战可能很快就会被克服。
