title: Low- but Not High-Frequency LFP Correlates with Spontaneous BOLD Fluctuations in Rat Whisker Barrel Cortex.
abstract: Resting-state magnetic resonance imaging (rsMRI) is thought to reflect ongoing spontaneous brain activity. However, the precise neurophysiological basis of rsMRI signal remains elusive. Converging evidence supports the notion that local field potential (LFP) signal in the high-frequency range correlates with fMRI response evoked by a task (e.g., visual stimulation). It remains uncertain whether this relationship extends to rsMRI. In this study, we systematically modulated LFP signal in the whisker barrel cortex (WBC) by unilateral deflection of rat whiskers. Results show that functional connectivity between bilateral WBC was significantly modulated at the 2 Hz, but not at the 4 or 6 Hz, stimulus condition. Electrophysiologically, only in the low-frequency range (<5 Hz) was the LFP power synchrony in bilateral WBC significantly modulated at 2 Hz, but not at 4- or 6-Hz whisker stimulation, thus distinguishing these 2 experimental conditions, and paralleling the findings in rsMRI. LFP power synchrony in other frequency ranges was modulated in a way that was neither unique to the specific stimulus conditions nor parallel to the fMRI results. Our results support the hypothesis that emphasizes the role of low-frequency LFP signal underlying rsMRI.
authors.affiliation: Neuroimaging Research Branch and.
authors.forename: Hanbing
authors.initials: H
authors.lastname: Lu
authors.affiliation: Neuroimaging Research Branch and.
authors.forename: Leiming
authors.initials: L
authors.lastname: Wang
authors.affiliation: Neuroimaging Research Branch and.|Integrative Neurobiology Section, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, USA.
authors.forename: William W
authors.initials: WW
authors.lastname: Rea
authors.affiliation: Neuroimaging Research Branch and.
authors.forename: Julia K
authors.initials: JK
authors.lastname: Brynildsen
authors.affiliation: Neuroimaging Research Branch and.|Department of Physiology, School of Medicine, University of Texas Health Science Center in San Antonio, TX 78229, USA.
authors.forename: Saul
authors.initials: S
authors.lastname: Jaime
authors.affiliation: Neuroimaging Research Branch and.|Psychiatry and Behavioral Sciences, Duke University School of Medicine, Durham, NC 27705, USA.
authors.forename: Yantao
authors.initials: Y
authors.lastname: Zuo
authors.affiliation: Neuroimaging Research Branch and.
authors.forename: Elliot A
authors.initials: EA
authors.lastname: Stein
authors.affiliation: Neuroimaging Research Branch and.
authors.forename: Yihong
authors.initials: Y
authors.lastname: Yang
mesh_terms: D000818:Animals; D001703:Biophysics; D002540:Cerebral Cortex / Q000098:blood supply* / Q000502:physiology*; D020927:Dexmedetomidine / Q000494:pharmacology; D004569:Electroencephalography; D005073:Evoked Potentials, Somatosensory / Q000187:drug effects / Q000502:physiology*; D005583:Fourier Analysis; D007839:Functional Laterality / Q000187:drug effects / Q000502:physiology; D006993:Hypnotics and Sedatives / Q000494:pharmacology; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D010100:Oxygen / Q000097:blood; D010812:Physical Stimulation; D051381:Rats; D017207:Rats, Sprague-Dawley; D014738:Vibrissae / Q000294:innervation*
chemical_list: D006993:Hypnotics and Sedatives; D020927:Dexmedetomidine; D010100:Oxygen
keywords: barrel cortex; delta oscillation; functional connectivity; gamma oscillation; spontaneous fluctuation