Effect Of Transcranial Direct Current Stimulation On Mental State Of BCI Users

There was repid development of brain Neuroscience in twenty-first Century.And the BCI will become the a hot research field.In the daily life,some stimuli can change the state of mind.Transcranial direct current stimulation is a nerve stimulation,it is noninvasive technique to regulate the cerebral cortex with constant low intensity direct current.This paper will combine the transcranial direct current stimulation and machine interface for a study.The main contents of this paper are as follows:(1)In this paper,we use time frequency ananlysis for EEG signal study.We use Hilbert-Huang tranform to deal with nonstationary signals such as EEG signals.First,we shoule removal fo EOG according to the feature of EOG.Then,we should complete the feature extraction of EEG base on Hilbert-Huang transform.Finally,we use deep learning neural networks to comlete the training base on characteristics of diferent states.The deep learning is used to distinguish different mental states.There are many ways to divide the state of mind,such as decision tree,svm and deep learning.But deep learing is a kind of imitation of the human neural structure.So this paper will mainly use the deep learning to divide the state of mind,and will compare with other methods such as dicision tree and svm,the training results of decision tree and support verctor machine were 92.1% and 94.5% respectively,while the result of deep learning training was 99%(2)Research of whether transcranial direct current stimulation can affect mental state or cognitive ability and whether the effect is obvious is very import in daily life.For example,it can improved the dirver's fatigue state if transcranial direct current stimulation has a obvious effect on mental state.And if there is a clear role in cognitive ability,it can be used to improve memory.So this paper will combine the study of the mental state and cognitive ability of transcranial direct current stimulation.So it is very important in daily life and the field of medicine.In this paper,we use ANOVA to analysis characteristic value before and after transcranial direct current stimulation,and the p-value greater then 0.05.We can get a conclusion: there is no sufficient evidence to show t DCS has a significant effect on the mental state.We will study the characteristics of EEG,and use Hilbert-Huang transform to extract EEG features,the use deep learing to automatic partition of fatigue state,and verify the effect of mental state through transcranial direct current stimulation.