Time and frequency dependent changes in resting state EEG functional connectivity following lipopolysaccharide challenge in rats.

Research has shown that inflammatory processes affect brain function and behavior through several neuroimmune pathways. However, high order brain functions affected by inflammation largely remain to be defined. Resting state functional connectivity of synchronized oscillatory activity is a valid app...

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Main Authors: Matthew A Albrecht, Chloe N Vaughn, Molly A Erickson, Sarah M Clark, Leonardo H Tonelli
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2018-01-01
Series:PLoS ONE
Online Access:http://europepmc.org/articles/PMC6231634?pdf=render
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author Matthew A Albrecht
Chloe N Vaughn
Molly A Erickson
Sarah M Clark
Leonardo H Tonelli
author_facet Matthew A Albrecht
Chloe N Vaughn
Molly A Erickson
Sarah M Clark
Leonardo H Tonelli
author_sort Matthew A Albrecht
collection DOAJ
description Research has shown that inflammatory processes affect brain function and behavior through several neuroimmune pathways. However, high order brain functions affected by inflammation largely remain to be defined. Resting state functional connectivity of synchronized oscillatory activity is a valid approach to understand network processing and high order brain function under different experimental conditions. In the present study multi-electrode EEG recording in awake, freely moving rats was used to study resting state connectivity after administration of lipopolysaccharides (LPS). Male Wistar rats were implanted with 10 cortical surface electrodes and administered with LPS (2 mg/kg) and monitored for symptoms of sickness at 3, 6 and 24 h. Resting state connectivity and power were computed at baseline, 6 and 24 h. Three prominent connectivity bands were identified using a method resistant to spurious correlation: alpha (5-15 Hz), beta-gamma (20-80 Hz), and high frequency oscillation (150-200 Hz). The most prominent connectivity band, alpha, was strongly reduced 6 h after LPS administration, and returned to baseline at 24 h. Beta-gamma connectivity was also reduced at 6 h and remained reduced at 24 h. Interestingly, high frequency oscillation connectivity remained unchanged at 6 h and was impaired 24 h after LPS challenge. Expected elevations in delta and theta power were observed at 6 h after LPS administration, when behavioral symptoms of sickness were maximal. Notably, gamma and high frequency power were reduced 6 h after LPS and returned to baseline by 24 h, when the effects on connectivity were more evident. Finally, increases in cross-frequency coupling elicited by LPS were detected at 6 h for theta-gamma and at 24 h for theta-high frequency oscillations. These studies show that LPS challenge profoundly affects EEG connectivity across all identified bands in a time-dependent manner indicating that inflammatory processes disrupt both bottom-up and top-down communication across the cortex during the peak and resolution of inflammation.
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spelling doaj.art-c43aff7593a544dba17b7db93feb03dc2022-12-22T02:35:47ZengPublic Library of Science (PLoS)PLoS ONE1932-62032018-01-011311e020698510.1371/journal.pone.0206985Time and frequency dependent changes in resting state EEG functional connectivity following lipopolysaccharide challenge in rats.Matthew A AlbrechtChloe N VaughnMolly A EricksonSarah M ClarkLeonardo H TonelliResearch has shown that inflammatory processes affect brain function and behavior through several neuroimmune pathways. However, high order brain functions affected by inflammation largely remain to be defined. Resting state functional connectivity of synchronized oscillatory activity is a valid approach to understand network processing and high order brain function under different experimental conditions. In the present study multi-electrode EEG recording in awake, freely moving rats was used to study resting state connectivity after administration of lipopolysaccharides (LPS). Male Wistar rats were implanted with 10 cortical surface electrodes and administered with LPS (2 mg/kg) and monitored for symptoms of sickness at 3, 6 and 24 h. Resting state connectivity and power were computed at baseline, 6 and 24 h. Three prominent connectivity bands were identified using a method resistant to spurious correlation: alpha (5-15 Hz), beta-gamma (20-80 Hz), and high frequency oscillation (150-200 Hz). The most prominent connectivity band, alpha, was strongly reduced 6 h after LPS administration, and returned to baseline at 24 h. Beta-gamma connectivity was also reduced at 6 h and remained reduced at 24 h. Interestingly, high frequency oscillation connectivity remained unchanged at 6 h and was impaired 24 h after LPS challenge. Expected elevations in delta and theta power were observed at 6 h after LPS administration, when behavioral symptoms of sickness were maximal. Notably, gamma and high frequency power were reduced 6 h after LPS and returned to baseline by 24 h, when the effects on connectivity were more evident. Finally, increases in cross-frequency coupling elicited by LPS were detected at 6 h for theta-gamma and at 24 h for theta-high frequency oscillations. These studies show that LPS challenge profoundly affects EEG connectivity across all identified bands in a time-dependent manner indicating that inflammatory processes disrupt both bottom-up and top-down communication across the cortex during the peak and resolution of inflammation.http://europepmc.org/articles/PMC6231634?pdf=render
spellingShingle Matthew A Albrecht
Chloe N Vaughn
Molly A Erickson
Sarah M Clark
Leonardo H Tonelli
Time and frequency dependent changes in resting state EEG functional connectivity following lipopolysaccharide challenge in rats.
PLoS ONE
title Time and frequency dependent changes in resting state EEG functional connectivity following lipopolysaccharide challenge in rats.
title_full Time and frequency dependent changes in resting state EEG functional connectivity following lipopolysaccharide challenge in rats.
title_fullStr Time and frequency dependent changes in resting state EEG functional connectivity following lipopolysaccharide challenge in rats.
title_full_unstemmed Time and frequency dependent changes in resting state EEG functional connectivity following lipopolysaccharide challenge in rats.
title_short Time and frequency dependent changes in resting state EEG functional connectivity following lipopolysaccharide challenge in rats.
title_sort time and frequency dependent changes in resting state eeg functional connectivity following lipopolysaccharide challenge in rats
url http://europepmc.org/articles/PMC6231634?pdf=render
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