The Research Of MI-BCI Technology In Optimized Thinking Task Mode

Brain-Computer-Interface(BCI)is a human machine interface that can directly realize the communication between the brain and peripheral device through the computer by processing the collected brain signals,without the help of normal information transmission channel consist of peripheral nerves and muscles.In terms of BCI research,the pattern of Motor-Imagery BCI's mental task can more accurately reflect our real thought and the normal state of our brain compared with other EEG paradigm.Furthermore,MI training can facilitate neural pathways which is close to the original injury pathways,and has important significant for limb movement function construction.MI-BCI is easily operated,and it doesn't need an external stimulation.Therefore,MI-BCI has become a hot research in BCI technology.MI-BCI also has many shortcomings yet,such as its brain signal feature is hard to extract,the number of the mental task which can be identified and the number of the effective control instructions is fewer than other BCI paradigm.The quality of The EEG signal is poor,and the BCI performance depends on different individuals.Also,we need to give subject a lot of training so that we can acquire high-quality mental task signals.Aiming at the shortcoming of MI-BCI,this article devote to improve the performance of the MI-BCI from the aspects of experimental design and mental task mode.This paper designed a novel MI experimental paradigm induced by real-time monitor video with the introduction of real-time video monitoring technology.The real-time monitor video platform is realized by a computer display which located in front of the body-disabled people(subject)and a camera which can acquire subject's video directly.The image of real-time monitor video is directly presented to the participants.The subject can see his real body and its motion scene when he executes motor imagery and what he need to do is just looking straight to the screen.This experiment paradigm has improved the participants' immersion degree and reduce fatigue of the subjects,it can induce a better quality of EEG signals.Through the analysis of the EEG signals which acquired in this experiment paradigm,we can also confirm the correctness of the conclusion.In addition,under this experimental design paradigm,this paper proposes a new mode of thinking task,by adopting specific imagination task paradigm,we can embody limb motor imagery tasks.The participants are required to imagine his shank be slightly raised or in a large range as much as possible.Then we process these MI signals based on different lower-limb raising range,extract their features,compare the difference of their features and find whether they have the divisibility.The divisibility of the EEG signal produced by the new model of the imagery task proposed in this paper,is expected to increase imagine movement patterns,and expand MI-BCI thinking task instruction set.