1. Department of Biomedical Engineering, Duke University, Durham, North Carolina;
2. Bioelectronics Research and Development, GlaxoSmithKline, Stevenage, United Kingdom
3. Department of Electrical and Computer Engineering, Duke University, Durham, North Carolina;
4. Department of Neurobiology, Duke University, Durham, North Carolina;
5. Department of Neurosurgery, Duke University, Durham, North Carolina; and