1. Graduate Program in Neuroscience; University of California, San Diego; La Jolla CA 92093 USA
2. Department of Physics; University of California, San Diego; La Jolla CA 92093 USA
3. Centre de Recherche Université Laval Robert-Giffard; Québec City Québec G1J 2R3 Canada
4. Department of Morphological Brain Science; Graduate School of Medicine; Kyoto University; Kyoto 606-8501 Japan
5. Department of Cell Biology; Duke University Medical Center; Durham NC 27710 USA
6. Department of Neuroscience; University of California, San Diego, School of Medicine; La Jolla CA 92093 USA
7. Section of Neurobiology; University of California, San Diego; La Jolla CA 92093 USA