Conclusions

Chapter 5

cortico-not been observed after cTBS-on-Sl. Lack of changes after cTBS-on-Sl demon strates that cTBS is a focal brain stimulation technique with a spatial sensitivity of at least two centimeters. Since no significant change on cortico-muscular coherence has been observed after cTBS-on-Sl, we can also speculate that SI does not primar ily modulate cortico-muscular coherence. Since we have measured the whole cortical activity, we found cTBS-on-Sl-specific changes of widespread cortical mechanisms by means of cortical power or cortico-cortical coherence. These effects outlasted the stimulation duration for two hours and highlights the sensitivity of the cortical activity to stimulation of sensory cortices.

Our study is the first study combining cTBS stimulation with quantitative analysis of EEG and EMG signals during isometric contraction task, thus providing the first evidence that cTBS can alter cortico -muscular/-cortical synchronized and oscillatory activity.

108

Acknowledgements

First of all, I would like to thank my thesis supervisor, Prof. Nobuki Murayama for accepting me in his laboratory for five years as a graduate student. Without his vision, support, patience and guidance, this work could not have been done. Second, yet foremost, I would like to acknowledge Prof. Yuki Hayashida. Not only for his scientific supervision and professional mentorship, I would like to thank him also for his encouragement and friendship for which I will always be grateful. I would like to thank other members of my committee: Prof. Takahiro Inoue and Prof. Tsuyoshi Usagawa. Next, I have to acknowledge Japanese Ministry of Education, Culture, Sports, Science and Technology (MEXT) for supporting me financially for the last five years. I would like to express my gratitude to Ms. Nornaili binti Mat Safri for her guidance as an excellent senior colleague. I would also like to thank Dr. Kaoru Matsunaga from Kinoh Hospital for collaborating with me in this research. I should also acknowledge Dr. Tomohiko Igasaki for teaching me various scientific tools in the lab. I would also like to thank all the present and former members of the Murayama and Hayashida Laboratories, for kindly participating in my experiments. I am also grateful to all the members of the Turkish community. Among them, I have to single

out Mr. Ugur Unal and Mr. Tolga 6z§en for their brotherhood during this long

journey. Here, I am not able to express how grateful I am to my girlfriend, Ozge.

Without her love and continuous support, every thing would be very difficult. Last but not least, I have to dedicate everything to my family: my mother, my father, my

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