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Title: Temporal coupling of field potentials and action potentials in the neocortex
Abstract

The local field potential (LFP) is an aggregate measure of group neuronal activity and is often correlated with the action potentials of single neurons. In recent years, investigators have found that action potential firing rates increase during elevations in power high‐frequency band oscillations (50–200 Hz range). However, action potentials also contribute to theLFPsignal itself, making the spike–LFPrelationship complex. Here, we examine the relationship between spike rates andLFPin varying frequency bands in rat neocortical recordings. We find that 50–180 Hz oscillations correlate most consistently with high firing rates, but that otherLFPbands also carry information relating to spiking, including in some cases anti‐correlations. Relatedly, we find that spiking itself and electromyographic activity contribute toLFPpower in these bands. The relationship between spike rates andLFPpower varies between brain states and between individual cells. Finally, we create an improved oscillation‐based predictor of action potential activity by specifically utilizing information from across the entire recorded frequency spectrum ofLFP. The findings illustrate both caveats and improvements to be taken into account in attempts to infer spiking activity fromLFP.

 
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NSF-PAR ID:
10050131
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
European Journal of Neuroscience
Volume:
48
Issue:
7
ISSN:
0953-816X
Page Range / eLocation ID:
p. 2482-2497
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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