Study Of Brain Computer Interfacr Based On Left And Right Hand Motor Imagery In Different Visual And Autitory Stimulation

Brain Computer Interface(BCI) is a communication system that can control external devices without depending on the brain's normal output channels. Using this equipment human could express their ideas or control surrounding devices without words or actions. It could help patients with physical disabilities who lost motor ability enhance communication with outside world to realize compensation of motor functions. BCI has become an active research area in Bioengineering.Human brain has motor imagery functions and the left and right hand motor imagery is one of them. Human can take advantage of this motor imagination to achieve communication with outside world. Visual and auditory perception and right and left hand movement is the most common perception and movement function in people's daily life, the main purpose of this paper is to give those patients who lose the ability of movement one self-control wheelchair design scheme, they can control the wheelchair to go and stop according to the indication of light ahead through their left and right hand motor imagery. At the same time it will exert a profound influence on the study of cognitive brain science research.In this article, subjects were tested under three stimuli: visual stimuli, auditory stimuli and visual-auditory stimulation, thus we could get three different results of left and right hand motor imagery to analyze the impacts of different visual and auditory stimulation on the human left and right hand motor imagery. STIM2 and Scan were used to achieve the experimental design and analyze the electroencephalogram signals off-line respectively.By analyzing the EEG waveform processed by Scan software off-line, we can found the differences between left and right hand motor imagery in different stimulation. In this paper, Public Space-Filter and support vector machine were combined to classify the experimental data collected, in the case of three different stimulus, we can still classify left and right hand well. By comparing classification results, we found that different visual and auditory stimulation had hardly impact on the classification accuracy of left and right hand motor imagery.