1. Department of Clinical Neurophysiology and the Department of Clinical Radiology, Kuopio University Hospital, Kuopio, Finland
2. Department of Applied Physics, University of Eastern Finland, Kuopio, Finland
3. Department of Neuroscience and Biomedical Engineering, Aalto University School of Science, Aalto, Finland
4. Institute of Biomedicine, School of Medicine, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland