Abstract
Local field potential (LFP) recording, is a very useful electrophysiological method to study brain processes. However, this method is criticized to record low frequency activity in a large aerea of extracellular space potentially contaminated by far sources. Here, we compare ground-referenced (RR) with differential recordins (DR) theoretically and experimentally. We analyze the electrical activity in the rat cortex with these both methods. Compared with the RR, the DR reveals the importance of local phasic oscillatory activities and their coherence between cortical areas. Finally, we argue that DR provides an access to a faithful functional connectivity quantization assessement owing to an increase in the signal to noise ratio. This may allow to measure the information propagation delay between two cortical structures.
Author summary Local field potential (LFP) recording, is a very useful electrophysiological method to study brain processes. However, this method is criticized to record low frequency activity in a large aerea of extracellular space potentially contaminated by far sources. Here, we compare ground-referenced (RR) with differential recordins (DR) theoretically and experimentally. We analyze the electrical activity in the rat cortex with these both methods. Compared with the RR, the DR reveals the importance of local phasic oscillatory activities and their coherence between cortical areas. Finally, we argue that DR provides an access to a faithful functional connectivity quantization assessement owing to an increase in the signal to noise ratio. This may allow to measure the information propagation delay between two cortical structures.