From the Department of Anesthesia, Critical Care, and Pain Medicine (O.A., K.J.P., R.V., M.J.P., P.G.H., K.E.H., J.R., A.L.S., L.G., E.T.P., J.L.W., E.N.B., P.L.P.) and Department of Neurology (M.B.W.), Massachusetts General Hospital, Boston, Massachusetts; Clinical Research Center, Massachusetts General Hospital, Boston, Massachusetts (K.H.); Harvard Medical School, Boston, Massachusetts (O.A., M.B.W., R.V., M.J.P., P.G.H., J.R., G.L., E.T.P., J.L.W., E.N.B., P.L.P.); Department of Brain and Cognitive Science, Massachusetts Institute of Technology, Cambridge, Massachusetts (E.N.B., P.L.P.); Harvard-Massachusetts Institute of Technology Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, Massachusetts (E.N.B.); and Institute for Medical Engineering and Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts (E.N.B.).