1. Microelectronics Lab (meLAB), James Watt School of Engineering, University of Glasgow 1 , Glasgow G12 8QQ, United Kingdom
2. Extreme Light Group, School of Physics and Astronomy, University of Glasgow 2 , Glasgow G12 8QQ, United Kingdom
3. Department of Epileptology, Hertie-Institute for Clinical Brain Research, University of Tübingen 3 , 72076 Tübingen, Germany
4. Department of Neural Dynamics and Magnetoencephalography, Hertie-Institute for Clinical Brain Research, University of Tübingen 4 , 72076 Tübingen, Germany
5. MEG-Center, University of Tübingen 5 , 72076 Tübingen, Germany