Theoretical considerations and supporting evidence for the primary role of source geometry on field potential amplitude and spatial extent

Frontiers in Cellular Neuroscience

Neuroscience

Valeriy A. Makarov¹  Julia Makarova²  Oscar Herreras²  Daniel Torres² 

[1] Institute for Interdisciplinary Mathematics, School of Mathematics, Universidad Complutense de Madrid, Madrid, Spain;Laboratory of Experimental and Computational Neurophysiology, Department of Translational Neuroscience, Cajal Institute, Spanish National Research Council, Madrid, Spain;

关键词: field potential;    source geometry;    spatial reach;    volume conduction;    network oscillations;    current source;    LFP;    source localization;   

DOI  :  10.3389/fncel.2023.1129097

 received in 2022-12-21, accepted in 2023-03-15,  发布年份 2023

来源: Frontiers

【 摘 要 】

Field potential (FP) recording is an accessible means to capture the shifts in the activity of neuron populations. However, the spatial and composite nature of these signals has largely been ignored, at least until it became technically possible to separate activities from co-activated sources in different structures or those that overlap in a volume. The pathway-specificity of mesoscopic sources has provided an anatomical reference that facilitates transcending from theoretical analysis to the exploration of real brain structures. We review computational and experimental findings that indicate how prioritizing the spatial geometry and density of sources, as opposed to the distance to the recording site, better defines the amplitudes and spatial reach of FPs. The role of geometry is enhanced by considering that zones of the active populations that act as sources or sinks of current may arrange differently with respect to each other, and have different geometry and densities. Thus, observations that seem counterintuitive in the scheme of distance-based logic alone can now be explained. For example, geometric factors explain why some structures produce FPs and others do not, why different FP motifs generated in the same structure extend far while others remain local, why factors like the size of an active population or the strong synchronicity of its neurons may fail to affect FPs, or why the rate of FP decay varies in different directions. These considerations are exemplified in large structures like the cortex and hippocampus, in which the role of geometrical elements and regional activation in shaping well-known FP oscillations generally go unnoticed. Discovering the geometry of the sources in play will decrease the risk of population or pathway misassignments based solely on the FP amplitude or temporal pattern.

【 授权许可】

Unknown   
Copyright © 2023 Herreras, Torres, Makarov and Makarova.