NEUROPHYSIOLOGY, BASIC AND CLINICALAcute and chronic effects of repeated 1 Hz rTMS on the temporal cortexKim, Won Supa,d; Lee, Minaa; Han, Joo Mana; Kim, Song E.a; Kim, Hee-Jinc; Kim, Bom Sahnb; Kim, Byung Gone; Lee, Hyang Woona Author Information Departments of aNeurology bNuclear Medicine, Ewha Womans University School of Medicine, Ewha Medical Research Institute cDepartment of Neurology, Hanyang University School of Medicine, Seoul dComputational Neuroscience Team, Division of Computational Sciences in Mathematics, National Institutes for Mathematical Sciences, Daejeon eBrain Disease Institute and Department of Neurology, Ajou University School of Medicine, Suwon, South Korea Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal's Website (www.neuroreport.com). Correspondence to Hyang Woon Lee, MD, PhD, Department of Neurology, Ewha Womans University School of Medicine and Ewha Medical Research Institute, 911-1, Mog-dong, Yangcheon-gu, Seoul 158-710, South Korea Tel: +82 2 2650 2673; fax: +82 2 2650 5958; e-mail: [email protected] Received March 5, 2012 Accepted March 22, 2012 NeuroReport: June 20, 2012 - Volume 23 - Issue 9 - p 540-545 doi: 10.1097/WNR.0b013e328354036f Buy SDC Metrics Abstract Electroencephalography amplitude, phase synchronization, and directionality of phase coupling within and between hemispheres were compared for different frequency components in 27 healthy individuals before and after 5 days of daily 1 Hz repetitive transcranial magnetic stimulation (rTMS), and at 2 weeks after the last session. Instantaneous amplitudes of α (8–13 Hz) and β (13–30 Hz) frequency components were increased after daily rTMS, the effects of which were declining over time, suggesting an adapting response with repeated rTMS sessions. The phase synchronization of electroencephalography increased significantly in the α frequency, especially the upper-α band (11–13 Hz), in both the frontal and the temporal areas, predominantly in the ipsilateral hemisphere. Asymmetric directional interactions of the upper-α band were stronger from the stimulated area to the contralateral hemisphere. No significant differences were found at 2 weeks after rTMS in any of these values. Focal 1 Hz rTMS induces an enhancement in the ipsilateral dominant corticocortical interaction drastically by interhemispheric asymmetric coupling from the stimulated cortical area with an adapting response with repeated sessions. This kind of method can be valuable for possible clinical applications in various neuropsychiatric conditions to study the therapeutic mechanisms of 1 Hz rTMS. © 2012 Lippincott Williams & Wilkins, Inc.