The EEG α wave mode shows chaotic characters and the frequency spectrum is entrained to the external photo-stimulation peak. This effect was observed exceedingly in the photo-sensitive children as compared with the n...The EEG α wave mode shows chaotic characters and the frequency spectrum is entrained to the external photo-stimulation peak. This effect was observed exceedingly in the photo-sensitive children as compared with the normal adults. The α spectrum shows asymmetric components with lower frequency-side tail. This spectrum shape could be realized from the computation in terms of the McCulloch-Pitts model and presented in comparison with the observed result. From this analysis, it turns out that the frequency spectrum analysis is most essential for the investigation of the EEG characteristics in comparison with simple waveform inspections in the time-passage. When light flashing frequencies come close to the alpha peak, the both peaks are fused in a giant single peak. These phenomena cannot be understood by the simple mechanical resonant theory but as discussed from the viewpoint of the soft chaotic dynamics of the neural network. Here the both peak intensities Iα and Iex are investigated under different conditions of ωex ωα, and ωα ωex, and it is shown that the entrainment effect is remarkably different in both cases. This result can be understood from the relating neuronal numbers and discussed.展开更多
Two different pathways in the brain have been implicated in the human visual perception process. One involves emotional cognition of face features, and the other involves spatial pattern cognition. In the present stud...Two different pathways in the brain have been implicated in the human visual perception process. One involves emotional cognition of face features, and the other involves spatial pattern cognition. In the present study, we used the event-related potential (ERP) method to examine temporal activation of the perception pathways at a fine time resolution of less than 10 ms. Four electrodes were attached onto their heads at O2, Pz, T4, and Fz, and ERP waveforms were observed on each electrode simultaneously. Nine portraits of actresses and 9 geometrical figures were chosen respectively, and presented on a CRT display in random order. The two types of figures elicited different responses. For portraits, the first significant N100 peak appeared on Pz and Fz, but not O2. For patterns, it started at N130 on O2. A significant response to portraits mostly appeared on T4, Pz, and Fz, and to patterns on O2, Pz, and Fz.展开更多
文摘The EEG α wave mode shows chaotic characters and the frequency spectrum is entrained to the external photo-stimulation peak. This effect was observed exceedingly in the photo-sensitive children as compared with the normal adults. The α spectrum shows asymmetric components with lower frequency-side tail. This spectrum shape could be realized from the computation in terms of the McCulloch-Pitts model and presented in comparison with the observed result. From this analysis, it turns out that the frequency spectrum analysis is most essential for the investigation of the EEG characteristics in comparison with simple waveform inspections in the time-passage. When light flashing frequencies come close to the alpha peak, the both peaks are fused in a giant single peak. These phenomena cannot be understood by the simple mechanical resonant theory but as discussed from the viewpoint of the soft chaotic dynamics of the neural network. Here the both peak intensities Iα and Iex are investigated under different conditions of ωex ωα, and ωα ωex, and it is shown that the entrainment effect is remarkably different in both cases. This result can be understood from the relating neuronal numbers and discussed.
文摘Two different pathways in the brain have been implicated in the human visual perception process. One involves emotional cognition of face features, and the other involves spatial pattern cognition. In the present study, we used the event-related potential (ERP) method to examine temporal activation of the perception pathways at a fine time resolution of less than 10 ms. Four electrodes were attached onto their heads at O2, Pz, T4, and Fz, and ERP waveforms were observed on each electrode simultaneously. Nine portraits of actresses and 9 geometrical figures were chosen respectively, and presented on a CRT display in random order. The two types of figures elicited different responses. For portraits, the first significant N100 peak appeared on Pz and Fz, but not O2. For patterns, it started at N130 on O2. A significant response to portraits mostly appeared on T4, Pz, and Fz, and to patterns on O2, Pz, and Fz.
