1. Department of Neurological Sciences, MEG laboratory, UNMC, Omaha, NE, USA
2. Wisconsin Airway Sensory Physiology Laboratory, University of Wisconsin – Whitewater, Whitewater, WI, USA
3. Department of Communication Sciences and Disorders, Northwestern University, Evanston, IL, USA
4. Department of Medicine, University of Chicago Medical Center, Chicago, IL, USA
5. Compumedics Europe GmbH, Hamburg, Germany