1. Department of ChemistryNational University of Singapore Singapore 117543 Singapore
2. Laboratory for Circuit and Behavioral PhysiologyRIKEN Center for Brain Science Wakoshi Saitama 351-0198 Japan
3. Singapore Institute of NeurotechnologyNational University of Singapore Singapore 117456 Singapore
4. Department of Biomedical EngineeringJohns Hopkins School of Medicine Baltimore MD 21205 USA
5. Research DepartmentNational Neuroscience Institute Singapore 308433 Singapore
6. Department of PhysiologyNational University of Singapore Singapore 117593 Singapore
7. Department of Life SciencesGraduate School of Arts and SciencesUniversity of Tokyo Tokyo Japan
8. Department of NeurologyJohns Hopkins School of Medicine Baltimore MD 21205 USA