Frequency dependence of signal power and spatial reach of the local field potential.
Despite its century-old use, the interpretation of local field potentials (LFPs), the low-frequency part of electrical signals recorded in the brain, is still debated. In cortex the LFP appears to mainly stem from transmembrane neuronal currents following synaptic input, and obvious questions regard...
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| Format: | Article |
| Language: | English |
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Public Library of Science (PLoS)
2013-01-01
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| Series: | PLoS Computational Biology |
| Online Access: | https://doi.org/10.1371/journal.pcbi.1003137 |
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| author | Szymon Łęski Henrik Lindén Tom Tetzlaff Klas H Pettersen Gaute T Einevoll |
| author_facet | Szymon Łęski Henrik Lindén Tom Tetzlaff Klas H Pettersen Gaute T Einevoll |
| author_sort | Szymon Łęski |
| collection | DOAJ |
| description | Despite its century-old use, the interpretation of local field potentials (LFPs), the low-frequency part of electrical signals recorded in the brain, is still debated. In cortex the LFP appears to mainly stem from transmembrane neuronal currents following synaptic input, and obvious questions regarding the 'locality' of the LFP are: What is the size of the signal-generating region, i.e., the spatial reach, around a recording contact? How far does the LFP signal extend outside a synaptically activated neuronal population? And how do the answers depend on the temporal frequency of the LFP signal? Experimental inquiries have given conflicting results, and we here pursue a modeling approach based on a well-established biophysical forward-modeling scheme incorporating detailed reconstructed neuronal morphologies in precise calculations of population LFPs including thousands of neurons. The two key factors determining the frequency dependence of LFP are the spatial decay of the single-neuron LFP contribution and the conversion of synaptic input correlations into correlations between single-neuron LFP contributions. Both factors are seen to give low-pass filtering of the LFP signal power. For uncorrelated input only the first factor is relevant, and here a modest reduction (<50%) in the spatial reach is observed for higher frequencies (>100 Hz) compared to the near-DC ([Formula: see text]) value of about [Formula: see text]. Much larger frequency-dependent effects are seen when populations of pyramidal neurons receive correlated and spatially asymmetric inputs: the low-frequency ([Formula: see text]) LFP power can here be an order of magnitude or more larger than at 60 Hz. Moreover, the low-frequency LFP components have larger spatial reach and extend further outside the active population than high-frequency components. Further, the spatial LFP profiles for such populations typically span the full vertical extent of the dendrites of neurons in the population. Our numerical findings are backed up by an intuitive simplified model for the generation of population LFP. |
| format | Article |
| id | doaj-art-977d93c0401840efb6d98b6d88e14b92 |
| institution | Kabale University |
| issn | 1553-734X 1553-7358 |
| language | English |
| publishDate | 2013-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS Computational Biology |
| spelling | doaj-art-977d93c0401840efb6d98b6d88e14b922025-08-20T03:25:34ZengPublic Library of Science (PLoS)PLoS Computational Biology1553-734X1553-73582013-01-0197e100313710.1371/journal.pcbi.1003137Frequency dependence of signal power and spatial reach of the local field potential.Szymon ŁęskiHenrik LindénTom TetzlaffKlas H PettersenGaute T EinevollDespite its century-old use, the interpretation of local field potentials (LFPs), the low-frequency part of electrical signals recorded in the brain, is still debated. In cortex the LFP appears to mainly stem from transmembrane neuronal currents following synaptic input, and obvious questions regarding the 'locality' of the LFP are: What is the size of the signal-generating region, i.e., the spatial reach, around a recording contact? How far does the LFP signal extend outside a synaptically activated neuronal population? And how do the answers depend on the temporal frequency of the LFP signal? Experimental inquiries have given conflicting results, and we here pursue a modeling approach based on a well-established biophysical forward-modeling scheme incorporating detailed reconstructed neuronal morphologies in precise calculations of population LFPs including thousands of neurons. The two key factors determining the frequency dependence of LFP are the spatial decay of the single-neuron LFP contribution and the conversion of synaptic input correlations into correlations between single-neuron LFP contributions. Both factors are seen to give low-pass filtering of the LFP signal power. For uncorrelated input only the first factor is relevant, and here a modest reduction (<50%) in the spatial reach is observed for higher frequencies (>100 Hz) compared to the near-DC ([Formula: see text]) value of about [Formula: see text]. Much larger frequency-dependent effects are seen when populations of pyramidal neurons receive correlated and spatially asymmetric inputs: the low-frequency ([Formula: see text]) LFP power can here be an order of magnitude or more larger than at 60 Hz. Moreover, the low-frequency LFP components have larger spatial reach and extend further outside the active population than high-frequency components. Further, the spatial LFP profiles for such populations typically span the full vertical extent of the dendrites of neurons in the population. Our numerical findings are backed up by an intuitive simplified model for the generation of population LFP.https://doi.org/10.1371/journal.pcbi.1003137 |
| spellingShingle | Szymon Łęski Henrik Lindén Tom Tetzlaff Klas H Pettersen Gaute T Einevoll Frequency dependence of signal power and spatial reach of the local field potential. PLoS Computational Biology |
| title | Frequency dependence of signal power and spatial reach of the local field potential. |
| title_full | Frequency dependence of signal power and spatial reach of the local field potential. |
| title_fullStr | Frequency dependence of signal power and spatial reach of the local field potential. |
| title_full_unstemmed | Frequency dependence of signal power and spatial reach of the local field potential. |
| title_short | Frequency dependence of signal power and spatial reach of the local field potential. |
| title_sort | frequency dependence of signal power and spatial reach of the local field potential |
| url | https://doi.org/10.1371/journal.pcbi.1003137 |
| work_keys_str_mv | AT szymonłeski frequencydependenceofsignalpowerandspatialreachofthelocalfieldpotential AT henriklinden frequencydependenceofsignalpowerandspatialreachofthelocalfieldpotential AT tomtetzlaff frequencydependenceofsignalpowerandspatialreachofthelocalfieldpotential AT klashpettersen frequencydependenceofsignalpowerandspatialreachofthelocalfieldpotential AT gauteteinevoll frequencydependenceofsignalpowerandspatialreachofthelocalfieldpotential |