1. Laboratory of Neural Plasticity, Faculties of Medicine and Science, Brain Research Institute, University of Zurich, 8057 Zurich, Switzerland.
2. Institute of Neuroinformatics, University of Zurich and Swiss Federal Institute of Technology (ETH) Zurich, 8057 Zurich, Switzerland.
3. Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge CB3 0HE, UK.
4. Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, UK.
5. Laboratory of Neural Circuit Dynamics, Faculties of Medicine and Science, Brain Research Institute, University of Zurich, 8057 Zurich, Switzerland.
6. Wellcome Trust–Medical Research Council Cambridge Stem Cell Institute, University of Cambridge, Cambridge CB2 1QR, UK.