Catherine Elizabeth Warnaby1, Marta Seretny, Roísín Ní Mhuircheartaigh, Richard Rogers, Saad Jbabdi, Jamie Sleigh, Irene Tracey. 1. Oxford Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB), Nuffield Department of Clinical Neurosciences, Oxford, United Kingdom (C.E.W., M.S., R.N.M., R.R., S.J., I.T.); Nuffield Division of Anaesthetics, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom (C.E.W., M.S., R.N.M., R.R., J.S., I.T.); Department of Anaesthetics, University of Edinburgh, Edinburgh, United Kingdom (M.S.); and Department of Anaesthesia, University of Auckland, Waikato Hospital, Hamilton, New Zealand (J.S.).
Abstract
BACKGROUND: It has been postulated that a small cortical region could be responsible for the loss of behavioral responsiveness (LOBR) during general anesthesia. The authors hypothesize that any brain region demonstrating reduced activation to multisensory external stimuli around LOBR represents a key cortical gate underlying this transition. Furthermore, the authors hypothesize that this localized suppression is associated with breakdown in frontoparietal communication. METHODS: During both simultaneous electroencephalography and functional magnetic resonance imaging (FMRI) and electroencephalography data acquisition, 15 healthy volunteers experienced an ultraslow induction with propofol anesthesia while a paradigm of multisensory stimulation (i.e., auditory tones, words, and noxious pain stimuli) was presented. The authors performed separate analyses to identify changes in (1) stimulus-evoked activity, (2) functional connectivity, and (3) frontoparietal synchrony associated with LOBR. RESULTS: By using an FMRI conjunction analysis, the authors demonstrated that stimulus-evoked activity was suppressed in the right dorsal anterior insula cortex (dAIC) to all sensory modalities around LOBR. Furthermore, the authors found that the dAIC had reduced functional connectivity with the frontoparietal regions, specifically the dorsolateral prefrontal cortex and inferior parietal lobule, after LOBR. Finally, reductions in the electroencephalography power synchrony between electrodes located in these frontoparietal regions were observed in the same subjects after LOBR. CONCLUSIONS: The authors conclude that the dAIC is a potential cortical gate responsible for LOBR. Suppression of dAIC activity around LOBR was associated with disruption in the frontoparietal networks that was measurable using both electroencephalography synchrony and FMRI connectivity analyses.
BACKGROUND: It has been postulated that a small cortical region could be responsible for the loss of behavioral responsiveness (LOBR) during general anesthesia. The authors hypothesize that any brain region demonstrating reduced activation to multisensory external stimuli around LOBR represents a key cortical gate underlying this transition. Furthermore, the authors hypothesize that this localized suppression is associated with breakdown in frontoparietal communication. METHODS: During both simultaneous electroencephalography and functional magnetic resonance imaging (FMRI) and electroencephalography data acquisition, 15 healthy volunteers experienced an ultraslow induction with propofol anesthesia while a paradigm of multisensory stimulation (i.e., auditory tones, words, and noxious pain stimuli) was presented. The authors performed separate analyses to identify changes in (1) stimulus-evoked activity, (2) functional connectivity, and (3) frontoparietal synchrony associated with LOBR. RESULTS: By using an FMRI conjunction analysis, the authors demonstrated that stimulus-evoked activity was suppressed in the right dorsal anterior insula cortex (dAIC) to all sensory modalities around LOBR. Furthermore, the authors found that the dAIC had reduced functional connectivity with the frontoparietal regions, specifically the dorsolateral prefrontal cortex and inferior parietal lobule, after LOBR. Finally, reductions in the electroencephalography power synchrony between electrodes located in these frontoparietal regions were observed in the same subjects after LOBR. CONCLUSIONS: The authors conclude that the dAIC is a potential cortical gate responsible for LOBR. Suppression of dAIC activity around LOBR was associated with disruption in the frontoparietal networks that was measurable using both electroencephalography synchrony and FMRI connectivity analyses.
Authors: William L Gross; Kathryn K Lauer; Xiaolin Liu; Christopher J Roberts; Suyan Liu; Suneeta Gollapudy; Jeffrey R Binder; Shi-Jiang Li; Anthony G Hudetz Journal: Anesthesiology Date: 2019-08 Impact factor: 7.892
Authors: Zirui Huang; Vijay Tarnal; Phillip E Vlisides; Ellen L Janke; Amy M McKinney; Paul Picton; George A Mashour; Anthony G Hudetz Journal: Cell Rep Date: 2021-05-04 Impact factor: 9.423
Authors: Annalotta Scheinin; Oskari Kantonen; Michael Alkire; Jaakko Långsjö; Roosa E Kallionpää; Kaike Kaisti; Linda Radek; Jarkko Johansson; Nils Sandman; Mikko Nyman; Mika Scheinin; Tero Vahlberg; Antti Revonsuo; Katja Valli; Harry Scheinin Journal: J Neurosci Date: 2020-12-28 Impact factor: 6.167