1 Department of Anesthesiology, University of Wisconsin-Madison, Madison, WI 53792, USA; Wellcome Department of Imaging Neuroscience and Department of Anaesthesia and Surgical Outcomes Research Centre, University College London Hospital, London, UK. Electronic address: rsanders4@wisc.edu.
2 University of Aachen, Aachen, Germany.
3 Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland.
4 Department of Anesthesiology, Division of Anesthesiology Critical Care Medicine, Vanderbilt University Medical Center, Nashville, TN, USA.