1 Department of Neurology, Duke University School of Medicine, Durham, NC 27710, USA. Electronic address: wayne.feng@duke.edu.
2 Department of Public Health Sciences, Medical University of South Carolina, Charleston, SC, USA.
3 Departments of Neurology, Physical Medicine & Rehabilitation, and Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA; Technology Enhancing Cognition and Health-Geriatric Research Education and Clinical Center and Human Engineering Research Labs, Veterans Affairs Pittsburgh Healthcare System, Pittsburgh, PA, USA.
4 Department of Neurology, University of Massachusetts Chan Medical School-Baystate, and Department of Biomedical Engineering, Institute of Applied Life Sciences, University of Massachusetts, Amherst, MA, USA.