1. Department of Rehabilitation Medicine, University of Washington, Seattle, Washington, USA
2. Center for Neurotechnology, University of Washington, Seattle, Washington, USA
3. Department of Electrical and Computer Engineering, University of Washington, Seattle, Washington, USA
4. Department of Mechanical Engineering, University of Washington, Seattle, Washington, USA
5. Department of Neurological Surgery, University of Washington, Seattle, Washington, USA
6. Department of Physiology and Biophysics, University of Washington, Seattle, Washington, USA