EEG Feature Research For Sensory Stimulation

More and more people are plagued by cerebral palsy, stroke, pap syndrome. At present, it is a serious challenge in rehabilitation science and technology workers how to provide a convenient and effective rehabilitation condition for patients. At the same time, the use of sensory stimulation (electrical stimulation and magnetic stimulation) in rehabilitation therapy becomes a focal point for researchers. And with the development and wide application of the brain computer interface technology, sensory evoked EEG has become a good experimental paradigm and application model in the BCI.At present, the studies of sensory evoked EEG focused on the brain-computer interface research, But the research in the rehabilitation is still at an exploratory stage. In Chinese-medicine theory, there is a close relation between the human body meridian and brain. In the thesis, import the low-frequency electronic pulse current into a specific body points combining the Chinese acupuncture, electrical nerve stimulation and the evoked potential paradigm. Extract the features of evoked potential based on the synchronization acquisition of human brain EEG. signal. Experiments proved that the electrical stimulation of acupuncture points can improve the beneficial ingredients of brain waves to promote the rehabilitation of the brain. The main work is as follows:(1) The design of sync signal generator. In order to realize the synchronization of the stimulate signals and the evoked EEG signals accurately, the signal synchronous generator was design. The synchronizer used AT89C2051, and used MAX232 to come ture the translator chip, the microcontroller I/O pins connected directly to the serial port. Thus provide high voltage for EEG amplifier, send commands to the relays by another I/O port, and control the stimulate signals imported to the human acupuncture points.(2) The design of EEG acquisition software. Take VC + + software system as a platform, and program based on MFC, then realize controlling the synchronization signal generator, EEG data collection, storage and waveform display.(3) Feature extraction of EEG. Using brain-computer interface competition standard database data, extract the left and right hand motor imagery EEG characteristics by bispectrum analysis and wavelet transform, and the simulation results have shown the feature extraction algorithm is feasible and effective. The results also showed that wavelet analysis method can effectively extract the evoked EEG time-frequency information. And the double-spectral analysis method can extract valuable high-level information, and there has been a strong advantage in dealing with nonlinear and suppressingGaussian noise.(4) The research on EEG characteristics of sensory stimulation. Design sensory evoked paradigm, and use the low-frequency electronic pulse device to stimulate the body acupuncture points. Obtain EEG signal by the EEG acquisition system, then extract the evoked EEG characteristics by the coherent averaging, wavelet transform and power spectrum estimation and so on. The results have shown that 30Hz intermittent wave stimulation can evoke P300 potentials well, promote brain a waves increase, and improve the brain function.This article combines the research of electrical stimulation based on acupuncture points with somatosensory evoked EEG, and explore the best way to import stimulus to Meridian, then prove the dynamic relationship between the brain and Meridian. It provides an effective method for the study of the nervous system diseases and rehabilitation therapy.