Signal Source Estimation Inside Brain Using Switching Voltage Divider

Visualization of neural activities inside the brain is useful for clarifying human brain function. Electroencephalogram (EEG) using a surface electrode is the most popular visualization method in laboratories, and estimation of the signal source using EEG has been extensively studied. Owing to the low spatial resolution of EEG, many surface electrodes are currently required for highly accurate estimates. In an attempt to improve the resolution, we developed a new EEG method in which the position information and potential of the signal source inside a human brain are obtained simultaneously from one signal electrode. A prototype device for proposed method has been developed, and experiments focused on EEG when the eyes were open and closed are conducted to validate our proposed method and device. Results show that the signal source position changes for the two conditions, and our method is plausible.