1. Leibniz-Institut für Wissensmedien, Tübingen, Germany
2. Centre for Mathematical Cognition, Loughborough University, Loughborough, UK
3. Department of Neurology, University Hospital, RWTH Aachen University, Aachen, Germany
4. Institute of Psychology, RWTH Aachen University, Aachen, Germany
5. LEAD Graduate School & Research Network, University of Tübingen, Tübingen, Germany