title: Disruption of cortical integration during midazolam-induced light sedation.
abstract: This work examines the effect of midazolam-induced light sedation on intrinsic functional connectivity of human brain, using a randomized, double-blind, placebo-controlled, cross-over, within-subject design. Fourteen healthy young subjects were enrolled and midazolam (0.03 mg/kg of the participant's body mass, to a maximum of 2.5 mg) or saline were administrated with an interval of one week. Resting-state fMRI was conducted before and after administration for each subject. We focus on two types of networks: sensory related lower-level functional networks and higher-order functions related ones. Independent component analysis (ICA) was used to identify these resting-state functional networks. We hypothesize that the sensory (visual, auditory, and sensorimotor) related networks will be intact under midazolam-induced light sedation while the higher-order (default mode, executive control, salience networks, etc.) networks will be functionally disconnected. It was found that the functional integrity of the lower-level networks was maintained, while that of the higher-level networks was significantly disrupted by light sedation. The within-network connectivity of the two types of networks was differently affected in terms of direction and extent. These findings provide direct evidence that higher-order cognitive functions including memory, attention, executive function, and language were impaired prior to lower-level sensory responses during sedation. Our result also lends support to the information integration model of consciousness.
authors: Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing, 100053, China.|Beijing Key Laboratory of Magnetic Resonance Imaging and Brain Informatics, Beijing, 100053, China.
authors: Peipeng
authors: P
authors: Liang
authors: Center for Cognition and Brain Disorders, Hangzhou Normal University, Hangzhou, 311121, China.|Zhejiang Key Laboratory for Research in Assessment of Cognitive Impairments, Hangzhou, 310015, China.|Department of Radiology and BRIC, University of North Carolina at Chapel Hill, NC 27599, USA.
authors: Han
authors: H
authors: Zhang
authors: Depart of Anesthesiology, Xuanwu Hospital, Capital Medical University, Beijing, 100053, China.
authors: Yachao
authors: Y
authors: Xu
authors: Center for Cognition and Brain Disorders, Hangzhou Normal University, Hangzhou, 311121, China.|Zhejiang Key Laboratory for Research in Assessment of Cognitive Impairments, Hangzhou, 310015, China.
authors: Wenbin
authors: W
authors: Jia
authors: Center for Cognition and Brain Disorders, Hangzhou Normal University, Hangzhou, 311121, China.|Zhejiang Key Laboratory for Research in Assessment of Cognitive Impairments, Hangzhou, 310015, China.
authors: Yufeng
authors: Y
authors: Zang
authors: Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing, 100053, China.|Beijing Key Laboratory of Magnetic Resonance Imaging and Brain Informatics, Beijing, 100053, China.
authors: Kuncheng
authors: K
authors: Li
mesh_terms: D000328:Adult; D002540:Cerebral Cortex / Q000187:drug effects*; D063132:Connectome / Q000379:methods*; D016292:Procedural Sedation; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D006993:Hypnotics and Sedatives / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D008606:Mental Processes / Q000187:drug effects*; D008874:Midazolam / Q000008:administration & dosage / Q000494:pharmacology*; D009415:Nerve Net / Q000187:drug effects*; D055815:Young Adult
chemical_list: D006993:Hypnotics and Sedatives; D008874:Midazolam
keywords: independent component analysis (ICA); midazolam; resting-state functional MRI (rs-fMRI); sedation