About the Authors

Eini Niskanen

Eini.Niskanen@uef.fi

Affiliations Department of Applied Physics, University of Eastern Finland, Kuopio, Finland, Department of Clinical Radiology, Kuopio University Hospital, Kuopio, Finland

Mervi Könönen

Affiliations Department of Clinical Radiology, Kuopio University Hospital, Kuopio, Finland, Department of Clinical Neurophysiology, Kuopio University Hospital, Kuopio, Finland

Sara Määttä

Affiliation Department of Clinical Neurophysiology, Kuopio University Hospital, Kuopio, Finland

Merja Hallikainen

Affiliation Institute of Clinical Medicine, Neurology, University of Eastern Finland, Kuopio, Finland

Miia Kivipelto

Affiliations Institute of Clinical Medicine, Neurology, University of Eastern Finland, Kuopio, Finland, Aging Research Center, Karolinska Institutet, Stockholm, Sweden

Silvia Casarotto

Affiliation Department of Clinical Sciences “L. Sacco”, Università degli Studi di Milano, Milan, Italy

Marcello Massimini

Affiliation Department of Clinical Sciences “L. Sacco”, Università degli Studi di Milano, Milan, Italy

Ritva Vanninen

Affiliations Department of Clinical Radiology, Kuopio University Hospital, Kuopio, Finland, Institute of Clinical Medicine, Clinical Radiology, University of Eastern Finland, Kuopio, Finland

Esa Mervaala

Affiliations Department of Clinical Neurophysiology, Kuopio University Hospital, Kuopio, Finland, Institute of Clinical Medicine, Clinical Neurophysiology, University of Eastern Finland, Kuopio, Finland

Jari Karhu

Affiliations Nexstim Ltd, Helsinki, Finland, Department of Physiology, University of Eastern Finland, Kuopio, Finland

Hilkka Soininen

Affiliations Institute of Clinical Medicine, Neurology, University of Eastern Finland, Kuopio, Finland, Department of Neurology, Kuopio University Hospital, Kuopio, Finland

Competing Interests

Professor Jari Karhu works as part-time medical chief officer at Nexstim Ltd. There are no patents, products in development or marketed products to declare. This does not alter the authors' adherence to all the PLoS ONE policies on sharing data and materials, as detailed online in the guide for authors.

Author Contributions

Conceived and designed the experiments: EN M. Könönen JK SM HS. Performed the experiments: EN M. Könönen SM. Analyzed the data: EN M. Könönen. Contributed reagents/materials/analysis tools: MH M. Kivipelto EM HS. Wrote the paper: EN M. Könönen SM SC MM RV EM JK HS. Provided intellectual content: EN M. Könönen SM SC MM EM JK RV HS.