S-Space College of Medicine/School of Medicine (의과대학/대학원) Dept. of Neurology (신경과학교실) Journal Papers (저널논문_신경과학교실)
내·외적인 자극을 받는 뇌파의 비선형 동력학적 특징
Nonlinear characterization of EEG under the internal and external stimuli
- 정기영; 김재문; 유철승; 이상훈
- Issue Date
- 대한임상신경생리학회지, Vol.4 No.1, pp. 28-33
- Backgrounds and objective : EEG reflect dynamic changes of continuous neuronal activities by internal and external stimuli. The aim of this study is to quantify nonlinearly the local dynamic differences among EEG data corresponding to different states of brain. Methods : EEG was recorded from twelve healthy normal subjects(mean age, 29.7 years; 8 men and 4 women) using digital EEG machine. 18-channel EEG data were selected during eyes closed(EC), eyes open(EO), and mental arithmetic( MA) in each subject. Correlation dimension(D2) and largest Lyapunov exponent(LLE) were calculated from three states and average value was mapped 2 dimensionally and compared with each other. Results : The distribution of D2 was relatively symmetric and its value was higher in frontal than in parieto-occipital region during EC. These findings were reversed during EO. Bilateral centro-temporo-parietal region showed high D2 value in MA compared with those in EC, which was more prominent in left side. LLE was larger than zero in all state and showed significant differences among EC, EO and MA(p=0.000). Conclusion : These results suggest that nonlinear analysis of EEG can quantify dynamic state of brain.