title: Propofol attenuates low-frequency fluctuations of resting-state fMRI BOLD signal in the anterior frontal cortex upon loss of consciousness.
abstract: Recent studies indicate that spontaneous low-frequency fluctuations (LFFs) of resting-state functional magnetic resonance imaging (rs-fMRI) blood oxygen level-dependent (BOLD) signals are driven by the slow (<0.1Hz) modulation of ongoing neuronal activity synchronized locally and across remote brain regions. How regional LFFs of the BOLD fMRI signal are altered during anesthetic-induced alteration of consciousness is not well understood. Using rs-fMRI in 15 healthy participants, we show that during administration of propofol to achieve loss of behavioral responsiveness indexing unconsciousness, the fractional amplitude of LFF (fALFF index) was reduced in comparison to wakeful baseline in the anterior frontal regions, temporal pole, hippocampus, parahippocampal gyrus, and amygdala. Such changes were absent in large areas of the motor, parietal, and sensory cortices. During light sedation characterized by the preservation of overt responsiveness and therefore consciousness, fALFF was reduced in the subcortical areas, temporal pole, medial orbital frontal cortex, cingulate cortex, and cerebellum. Between light sedation and deep sedation, fALFF was reduced primarily in the medial and dorsolateral frontal areas. The preferential reduction of LFFs in the anterior frontal regions is consistent with frontal to sensory-motor cortical disconnection and may contribute to the suppression of consciousness during general anesthesia.
authors.affiliation: Department of Radiology, Medical College of Wisconsin, Milwaukee, WI, USA. Electronic address: xiliu@mcw.edu.
authors.forename: Xiaolin
authors.initials: X
authors.lastname: Liu
authors.affiliation: Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA.
authors.forename: Kathryn K
authors.initials: KK
authors.lastname: Lauer
authors.affiliation: Department of Biophysics, Medical College of Wisconsin, Milwaukee, WI, USA.
authors.forename: B
authors.initials: B
authors.lastname: Douglas Ward
authors.affiliation: Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA.
authors.forename: Christopher
authors.initials: C
authors.lastname: Roberts
authors.affiliation: Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA.
authors.forename: Suyan
authors.initials: S
authors.lastname: Liu
authors.affiliation: Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA.
authors.forename: Suneeta
authors.initials: S
authors.lastname: Gollapudy
authors.affiliation: Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA.
authors.forename: Robert
authors.initials: R
authors.lastname: Rohloff
authors.affiliation: Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA.
authors.forename: William
authors.initials: W
authors.lastname: Gross
authors.affiliation: Department of Biophysics, Medical College of Wisconsin, Milwaukee, WI, USA.
authors.forename: Guangyu
authors.initials: G
authors.lastname: Chen
authors.affiliation: Department of Biophysics, Medical College of Wisconsin, Milwaukee, WI, USA.
authors.forename: Zhan
authors.initials: Z
authors.lastname: Xu
authors.affiliation: Department of Neurology, Medical College of Wisconsin, Milwaukee, WI, USA.
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Binder
authors.affiliation: Department of Biophysics, Medical College of Wisconsin, Milwaukee, WI, USA.
authors.forename: Shi-Jiang
authors.initials: SJ
authors.lastname: Li
authors.affiliation: Department of Anesthesiology and Center for Consciousness Science, University of Michigan, Ann Arbor, USA. Electronic address: ahudetz@med.umich.edu.
authors.forename: Anthony G
authors.initials: AG
authors.lastname: Hudetz
mesh_terms: D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000502:physiology; D063132:Connectome / Q000379:methods*; D016292:Procedural Sedation; D003243:Consciousness / Q000187:drug effects*; D054810:Deep Sedation; D005260:Female; D006801:Humans; D006993:Hypnotics and Sedatives / Q000008:administration & dosage / Q000494:pharmacology*; D008279:Magnetic Resonance Imaging; D008297:Male; D017397:Prefrontal Cortex / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000502:physiology; D015742:Propofol / Q000008:administration & dosage / Q000494:pharmacology*; D055815:Young Adult
chemical_list: D006993:Hypnotics and Sedatives; D015742:Propofol
keywords: Fractional amplitude of low-frequency fluctuation (fALFF); Loss of consciousness; Propofol sedation; Resting-state fMRI; Spontaneous neural activity