Propofol-induced Changes in α-β Sensorimotor Cortical Connectivity. (February 2018)

• Record Type: Journal Article
• Authors: Malekmohammadi, Mahsa; AuYong, Nicholas; Price, Collin M.; Tsolaki, Evangelia; Hudson, Andrew E.; Pouratian, Nader
• Is Part Of: Anesthesiology. Volume 128:Number 2(2018)
• Publication Date: 2018-02
• Subjects: Anesthesiology -- Periodicals; Anesthetics -- Periodicals; Anesthesia -- Periodicals; 617.9605
• DOI: 10.1097/ALN.0000000000001940
• Languages: English
• ISSNs: 0003-3022

Abstract

Abstract : Background: Anesthetics are believed to alter functional connectivity across brain regions. However, network-level analyses of anesthesia, particularly in humans, are sparse. The authors hypothesized that propofol-induced loss of consciousness results in functional disconnection of human sensorimotor cortices underlying the loss of volitional motor responses. Methods: The authors recorded local field potentials from sensorimotor cortices in patients with Parkinson disease (N = 12) and essential tremor (N = 7) undergoing deep brain stimulation surgery, before and after propofol-induced loss of consciousness. Local spectral power and interregional connectivity (coherence and imaginary coherence) were evaluated separately across conditions for the two populations. Results: Propofol anesthesia caused power increases for frequencies between 2 and 100 Hz across the sensorimotor cortices and a shift of the dominant spectral peak in α and β frequencies toward lower frequencies (median ± SD peak frequency: 24.5 ± 2.6 Hz to 12.8 ± 2.3 Hz in Parkinson disease; 13.8 ± 2.1 Hz to 12.1 ± 1.0 Hz in essential tremor). Despite local increases in power, sensorimotor cortical coherence was suppressed with propofol in both cohorts, specifically in β frequencies (18 to 29 Hz) for Parkinson disease and α and β (10 to 48 Hz) in essential tremor. Conclusions: The decrease in functional connectivity between sensory and motor cortices, despite an increase in local spectral power, suggests that propofol causes a functional disconnection of cortices with increases in autonomous activity within cortical regions. This pattern occurs across diseases evaluated, suggesting that these may be generalizable effects of propofol in patients with movement disorders and beyond. Sensorimotor network disruption may underlie anesthetic-induced loss of volitional control. Abstract : Although propofol administration led to a local power increase in oscillations in both the sensory and motor cortices, the coupling between these two regions was significantly reduced. The results support the premise that propofol induces a functional disconnection between cortical areas even though local activity in these areas may increase.Supplemental Digital Content is available in the text.