1. University of TampereMedical SchoolPO Box 60733101TampereFinland
2. Institute of Higher Nervous Activity and Neurophysiology, RASMoscowRussia
3. Department of NeurologyThe Johns Hopkins UniversityBaltimoreMD21287‐7519USA
4. Department of NeurosurgeryTampere University HospitalTampereFinland
5. Department of Mental Health and Alcohol ResearchNational Public Health InstitutePO Box 71900101HelsinkiFinland