CN113128384A - Brain-computer interface software key technical method of stroke rehabilitation system based on deep learning - Google Patents
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Abstract
A stroke rehabilitation system brain-computer interface software key technical method based on deep learning belongs to the technical field of deep learning. According to the invention, in the electroencephalogram signal feature extraction and classification stage, the autoregressive model and the sample entropy are adopted to extract features of the electroencephalogram signal, and the classification is carried out by utilizing the CNN algorithm, so that the accuracy of electroencephalogram signal classification can be improved, and the electroencephalogram signal classification method can be applied to the brain-computer interface software of a stroke rehabilitation system to realize rehabilitation treatment of stroke patients.
Description
Technical Field
The invention belongs to the technical field of deep learning.
Background
At present, the Brain electrical signal correlation technology and Brain Computer Interface (BCI) technology are continuously developed, and the application of the Brain electrical signal in the recovery of stroke is more and more extensive. Relevant research results show that the motor imagery electroencephalogram signals of stroke patients can help them to carry out effective rehabilitation treatment. Researches find that the activity of the electroencephalogram signals can not change due to the damage of limbs and muscles, and the electroencephalogram signals can still accurately reflect the electrophysiological activity performed by the cerebral cortex of the human beings. Therefore, the related art of brain-computer interface based on motor imagery has become a key point in the rehabilitation research of stroke patients.
The deep learning is different from the traditional machine learning method, an end-to-end learning mode is realized, and the original data is used as model input and is directly mapped to generate the output of the model. The more classical deep learning models include a convolutional neural network and a cyclic neural network. However, the method has disadvantages that, for example, a deep neural network requires a large amount of data to train a model, and it is difficult to sufficiently train the model for most small-scale data sets; lack of sufficient label data to effectively train the deep learning model; there is a huge computational demand. Deep forest (gcForest) is a feature fusion model as a deep neural network model including a convolutional neural network and a cyclic neural network, and has been a result of attention in various fields such as vision, text, and speech. In deep forests, the strategy of multi-granularity scanning is used, so that the relevance between the features captured by the model can be helped, and the capability of model characterization learning is further improved.
The traditional electroencephalogram signal processing method mainly has the time filtering, the space filtering, the principal component analysis, the independent component analysis and the like. At present, the mainstream electroencephalogram feature extraction method is a power spectral density and public space mode algorithm. The traditional machine learning method is to apply a proper classification algorithm to classify samples on the basis of finishing data preprocessing and artificially constructing sample characteristics. In the subject, a deep learning mode is tried to be adopted, the algorithm is further optimized, and the processing speed and accuracy of the algorithm are improved.
The invention in this field of China is as follows: the data enhancement-based convolutional neural network motor imagery electroencephalogram classification method [1] classifies electroencephalogram signals through a convolutional neural network, and the average accuracy of the obtained second, third and fourth classification tasks respectively reaches 87.32%, 76.26% and 64.72%. The method [2] for recognizing the characteristics of the motor imagery electroencephalogram signals based on the LFFCNN-GRU algorithm model extracts the frequency domain characteristics of the electroencephalogram signals by using a convolutional neural network based on interlayer characteristic fusion, and further extracts the time domain characteristics of the electroencephalogram signals by using a gated cyclic network. The electroencephalogram identification method [3] based on CWT and MLMSFFCNN fully extracts time, frequency and space domain feature information of signals by utilizing MLMSFFCNN feature fusion capability and multi-resolution computing capability, and improves classification accuracy.
[1] Liuyue, Dubin, Yuekang, Tiankuang. convolutional neural network motor imagery electroencephalogram classification method based on data enhancement [ P ]. Beijing City: CN111950366A,2020-11-17.
[2] Mao Xuefeng, Shexiangrong, Zhang Yi, Rouyan, a motor imagery electroencephalogram signal feature identification method based on LFFCNN-GRU algorithm model [ P ]. Chongqing city: CN111950455A,2020-11-17.
[3] Li Minai, Korea Jianfu, Yangjin Fu, Sun Yan jade, CWT and MLMSFFCNN-based electroencephalogram identification method [ P ]. Beijing City: CN111582041A,2020-08-25.
Disclosure of Invention
According to the invention, in the electroencephalogram signal feature extraction and classification stage, the autoregressive model and the sample entropy are adopted to extract features of the electroencephalogram signal, and the classification is carried out by utilizing the CNN algorithm, so that the accuracy of electroencephalogram signal classification can be improved, and the electroencephalogram signal classification method can be applied to the brain-computer interface software of a stroke rehabilitation system to realize rehabilitation treatment of stroke patients.
The technical scheme of the invention comprises the following stages: in the electroencephalogram signal acquisition and preprocessing stage, an electroencephalogram signal acquisition system is used for acquiring an EEG signal, then the acquired EEG signal is preprocessed by EEGLAB to remove electrooculogram, artifacts and the like, the electroencephalogram signal with noise filtered is obtained, and the dimensionality reduction is carried out through principal component analysis; in the EEG signal feature extraction stage, an Autoregressive Model (Autoregressive Model) and sample entropy are respectively utilized to extract EEG signal features of motor imagery, two types of linear and nonlinear signal features can be respectively obtained from a frequency domain and a space domain, wherein AR Model parameters are used as feature vectors; and a characteristic classification stage, namely classifying the electroencephalogram signals based on a CNN (convolutional neural network) design classifier, respectively adding two types of signal characteristics obtained by characteristic extraction into the CNN for classification to obtain different classification results, and integrating the results according to a certain weight to obtain a final classification result.
The invention improves the classification accuracy of the motor imagery electroencephalogram signals by simultaneously extracting the characteristics of frequency domain electroencephalogram signals, spatial domain electroencephalogram signals, linear electroencephalogram signals and nonlinear electroencephalogram signals.
Description of the drawings:
FIG. 1 is a flow chart of the present invention.
The specific implementation mode is as follows:
1. electroencephalogram signal acquisition stage
The invention uses an EEG signal acquisition instrument to acquire signals, selects a sampling frequency of 250Hz, arranges electrodes according to an international 10-20 standard electrode arrangement method, selects a plurality of healthy subjects, respectively acquires left-hand and right-hand motor imagery EEG signals, uses a band-stop filter to filter, and selects 1Hz-50Hz EEG signals.
2. Preprocessing stage of EEG signal
The electroencephalogram signal of the human body is very weak, and the background noise is very large. Due to the influence of external factors such as instruments and the muscle movement of the human body, various noise interferences such as baseline drift interference, power frequency interference, myoelectric interference, electrode contact noise and the like can be generated when the electroencephalogram signals are collected. The above interference will affect both the time domain analysis and the frequency domain analysis of the EEG.
The main purposes of preprocessing are to improve the signal-to-noise ratio of the brain electrical signal, stabilize the baseline, reduce artifacts, and remove glitches. The traditional preprocessing method generally adopts Fourier transform, but because the electroencephalogram signals have the characteristic of random instability, the effect of denoising the electroencephalogram signals by adopting the Fourier transform is not ideal. In recent years, with the deep research on electroencephalogram signals, methods such as wavelet transformation and independent component analysis gradually play an important role in signal preprocessing. And the fast fixed point algorithm (FastICA) in the independent component analysis has the characteristics of parallelism, distribution, less occupied memory, fast convergence and the like.
EEGLAB is used for preprocessing, FastICA is used for denoising experimental data, and principal component analysis is used for dimensionality reduction of the data.
3. Feature extraction stage
After EEG signal preprocessing, the processed EEG signal is respectively subjected to feature extraction by using an Autoregressive Model (Autoregressive Model) and sample entropy to obtain two types of signal features.
3.1 Autoregressive Model (Autoregensive Model)
An Autoregressive Model (Autoregressive Model) is a common form in a time series and utilizes a linear combination of random variables at a plurality of moments in the early stage to describe a linear regression Model of random variables at a certain moment in the later stage. Suppose the EEG signal sequence is y1,y2,…,ynThe autoregressive model of order P (abbreviated AR (P)) indicates y in the sequencetIs a function of the linear combination of the first P sequences and the error term, and the general form of the mathematical model is:
wherein the content of the first and second substances,is a constant term that is used to determine,is a model parameter, etIs white noise with a mean value of 0 and a variance σ. In the inventionAs EEG signal feature vectors.
3.2 sample entropy
The sample entropy is a nonlinear analysis method, and can reflect the nonlinear characteristics of the electroencephalogram signal by measuring the complexity of the electroencephalogram signal.
Let us say the electroencephalogram one-dimensional time sequence is { y (i) }, i ═ 1,2, …, n, where y (i) denotes the electroencephalogram signal sequence of the ith second, and n denotes the total time length. The sample entropy can be calculated as follows:
(1) forming m-dimensional vectors by the sequence { y (i) } in sequence, and selecting m as 2 in the invention, namely
Ym(i)=[y(i)y(i+1)…y(i+m-1)]
i=1,2,…,n-m+1
(2) For each time i, a vector Y is calculatedm(i) And vector Ym(j) Is a distance therebetween, i.e.
d[Ym(i),Ym(j)]=max|y(i+k)-y(j+k)|
k=0,1,…,m-1;i=1,2,…,n-m+1;i≠j
(3) Given threshold r (r)>0) In the invention, r is 0.2 times of the standard deviation of the original time sequence, and d [ Y ] is counted for each time im(i),Ym(j)]A number less than r, is recordedAnd the ratio of the number to the total number of distances n-m is recorded asNamely, it is
(5) Forming m + 1-dimensional vectors by the sequence { y (i) } in sequence, and repeating the steps (1) to (4) to obtainAnd Bm+1(r)
(6) The sample entropy of the sequence y (i) } is
In practical calculation, because the sequence length is limited, the finally obtained sample entropy estimated value when the sequence length is n is as follows
sampEn(m,r,n)=-ln[Bm+1(r)/Bm(r)]}
The specific steps of extracting the nonlinear characteristics of the electroencephalogram signal by utilizing the sample entropy are as follows: firstly, adding a sliding time window with the length of 1s to the electroencephalogram signal, calculating the sample entropy of the electroencephalogram signal, moving the window by one sampling point each time, calculating the sample entropy of the electroencephalogram signal of the next 1s time window until the sample entropy of the electroencephalogram signal of the last 1s time window is calculated, thereby obtaining the time sequence of the sample entropy of the group of electroencephalogram signals, and then superposing and averaging the group of sample entropy sequences to obtain the sample entropy of the group of sample electroencephalogram signal data.
4. Feature classification phase
The invention uses a Convolutional Neural Network (CNN) as a classifier to classify the two extracted types of feature vectors respectively, and then the classification results of the two types of feature vectors are weighted to finally obtain the classification results.
4.1CNN construction and principles thereof
The CNN used by the invention consists of six convolutional layers, two pooling layers and two full-connecting layers, and the sequence is as follows: the three-layer rolling layer, the one-layer pooling layer, the three-layer rolling layer, the one-layer pooling layer and the two full-connection layers are all realized by using Tensorflow.
Dividing the data set into training set and test set according to the ratio of 7:3, and extracting two types of feature vectors obtained by feature extraction(where i ∈ [1, n ]]N represents the total time length) and SEi={i∈[1,n]| sampEn (m, r, i) } (whichWhere n represents the total time length) as input, three prediction possibilities are output (T0, T1, T2, respectively representing resting state, imaginary left hand, imaginary right hand). An Adam optimizer was used, and the learning rate was 1 x 10-5.
(1) Convolutional layer (convolutional layer): the size of each convolution kernel of each convolution layer in the convolution neural network is 3 x 3, and the parameter of each convolution unit is obtained by optimization through a back propagation algorithm, so that different input features can be extracted.
(2) Pooling layer (Pooling layer): after the convolution, features of large dimensions (size [28 x 20 x 64]) were obtained, and the features were cut into regions of [2,2], respectively, the maximum of which was taken to obtain new features of smaller dimensions (size [14 x 10 x 64 ]).
(3) Supervised learning
The model uses supervised learning, using a back propagation algorithm to calculate the parameters of each convolution unit.
The main process is as follows:
calculating a loss function using Euclidean distances
E=(x-pred)2
Where x is the value of the actual feature vector and pred is the value of the predicted feature vector.
Propagating the loss function from the output layer back to the hidden layer until propagating to the input layer; in the back propagation process, adjusting the value of the parameter of each convolution unit according to a loss function; and continuously iterating the process until convergence.
4.2 weighted integration
In the last step, the results of the classification of the two types of feature vectors are summed by respectively weighting 50% to obtain the final prediction result. As can be seen from the above, the present invention,and SEpredThe prediction result vectors are respectively two kinds of feature vectors in the form ofAnd wherein predi(i=T0,T1,T2) The predicted probability that the group of brain electrical signals in the model is of the second class is shown. The final prediction result vector is
The final prediction result can be obtained by final.
Claims (2)
1. A stroke rehabilitation system brain-computer interface software key technical method based on deep learning is characterized by comprising the following stages: in the electroencephalogram signal acquisition and preprocessing stage, an electroencephalogram signal acquisition system is used for acquiring an EEG signal, then the acquired EEG signal is preprocessed by EEGLAB to remove electrooculogram and artifacts, the electroencephalogram signal with noise filtered is obtained, and the dimensionality is reduced through principal component analysis;
in the electroencephalogram signal feature extraction stage, an autoregressive model and sample entropy are respectively utilized to extract the features of a motor imagery EEG signal, and linear and nonlinear signal features can be respectively obtained from a frequency domain and a space domain, wherein AR model parameters are used as feature vectors; and a characteristic classification stage, namely classifying the electroencephalogram signals based on a CNN (convolutional neural network) design classifier, respectively adding two types of signal characteristics obtained by characteristic extraction into the CNN for classification to obtain different classification results, and integrating the results to obtain a final classification result.
2. The method of claim 1, wherein:
1) electroencephalogram signal acquisition stage
Collecting signals by using an electroencephalogram signal collector, selecting a sampling frequency of 250Hz, arranging electrodes according to an international 10-20 standard electrode arrangement method, selecting a plurality of healthy subjects, respectively collecting left-hand and right-hand motor imagery electroencephalogram signals, filtering by using a band-stop filter, and selecting 1Hz-50Hz EEG signals;
2) preprocessing stage of electroencephalogram signals
EEGLAB is used for preprocessing, FastICA is used for denoising experimental data, and principal component analysis is used for reducing the dimension of the data;
3) a feature extraction stage
After preprocessing, respectively performing feature extraction on the processed EEG signal by using an autoregressive model and sample entropy to obtain two types of signal features;
3.1 autoregressive model
The autoregressive model describes a linear regression model of random variables at a later moment by utilizing linear combinations of the random variables at a plurality of earlier moments; suppose the EEG signal sequence is y1,y2,...,ynThe autoregressive model of order P, denoted AR (P), indicates y in the sequencetIs a function of the linear combination of the first P sequences and the error term, and the mathematical model is:
wherein the content of the first and second substances,is a constant term that is used to determine,is a model parameter, etWhite noise with mean 0 and variance σ; will be provided withAs EEG signal feature vectors;
3.2 sample entropy
Setting the electroencephalogram signal one-dimensional time sequence as { y (i) }, i ═ 1,2,. and n, wherein y (i) represents the electroencephalogram signal sequence of the ith second, and n represents the total time length; the sample entropy is calculated as follows:
(1) forming m-dimensional vectors by the sequence { y (i) } in sequence, and selecting m as 2, namely
Ym(i)=[y(i)y(i+1)...y(i+m-1)]
i=1,2,...,n-m+1
(2) For each time i, a vector Y is calculatedm(i) And vector Ym(j) Is a distance therebetween, i.e.
d[Ym(i),Ym(j)]=max|y(i+k)-y(j+k)|
k=0,1,...,m-1;i=1,2,...,n-m+1;i≠j
(3) Given a threshold r, r > 0, where r is 0.2 times the standard deviation of the original time series, d [ Y ] is counted for each i timem(i),Ym(j)]A number less than r, is recordedAnd the ratio of the number to the total number of distances n-m is recorded asNamely, it is
(5) Forming m + 1-dimensional vectors by the sequence { y (i) } in sequence, and repeating the steps (1) to (4) to obtainAnd Bm+1(r)
(6) The sample entropy of the sequence y (i) } is
Obtaining a sample entropy estimated value when the sequence length is n as
sampEn(m,r,n)=-ln[Bm+1(r)/Bm(r)]}
The specific steps of extracting the nonlinear characteristics of the electroencephalogram signal by utilizing the sample entropy are as follows: firstly, adding a sliding time window with the length of 1s to the electroencephalogram signal, calculating the sample entropy of the electroencephalogram signal, moving the window by one sampling point each time, calculating the sample entropy of the electroencephalogram signal of the next 1s time window until the sample entropy of the electroencephalogram signal of the last 1s time window is calculated, thereby obtaining the time sequence of the sample entropy of the group of electroencephalogram signals, and then superposing and averaging the group of sample entropy sequences to obtain the sample entropy of a group of sample electroencephalogram signal data;
4) stage of feature classification
Using a convolutional neural network CNN as a classifier to classify the two extracted types of feature vectors respectively, and then performing weighting processing on classification results of the two types of feature vectors respectively to finally obtain a classification result;
4.1CNN construction and principles thereof
The CNN used consists of six convolutional layers, two pooling layers and two full-link layers in the following sequence: the three-layer rolling layer, the one-layer pooling layer, the three-layer rolling layer, the one-layer pooling layer and the two full-connection layers are all realized by using Tensorflow;
dividing the data set into training set and test set, and extracting the two kinds of feature vectorsWhere i ∈ [1, n ]]N represents the total time length; and SEi={i∈[1,n]I sampEn (m, r, i) } is used as input, three kinds of prediction possibility are available for output, T0, T1 and T2 respectively represent a rest state, a left imagination hand and a right imagination hand; an Adam optimizer is used, and the learning rate is 1 x 10^ -5;
A. and (3) rolling layers: the size of each convolution kernel of each convolution layer in the convolution neural network is 3 x 3, and the parameter of each convolution unit is obtained by optimization through a back propagation algorithm, so that different input features are extracted;
B. a pooling layer: obtaining a feature with the dimension of [28 × 20 × 64] after the convolution layer, cutting the feature into regions with the dimensions of [2,2], and taking the maximum value to obtain a new feature with the dimension of [14 × 10 × 64 ];
C. supervised learning
Calculating parameters of each convolution unit by using a back propagation algorithm;
calculating a loss function using Euclidean distances
E=(x-pred)2
Wherein, x is the value of the actual feature vector, and pred is the value of the predicted feature vector;
propagating the loss function from the output layer back to the hidden layer until propagating to the input layer; in the back propagation process, adjusting the value of the parameter of each convolution unit according to a loss function; continuously iterating the above process until convergence;
4.2 weighted integration
In the last step, the results after the two types of feature vectors are classified adopt a method of respectively weighting 50% to sum to obtain a final prediction result; as can be seen from the above, the present invention,and SEpredThe prediction result vectors are respectively two kinds of feature vectors in the form ofAnd wherein predi(i=T0,T1,T2) Is shown in this modelThe prediction probability of the group of electroencephalogram signals in the model as the ith class; the final prediction result vector is
Final prediction result is final.
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
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CN114082169A (en) * | 2021-11-22 | 2022-02-25 | 江苏科技大学 | Disabled hand soft body rehabilitation robot motor imagery identification method based on electroencephalogram signals |
CN114664434A (en) * | 2022-03-28 | 2022-06-24 | 上海韶脑传感技术有限公司 | Cerebral apoplexy rehabilitation training system for different medical institutions and training method thereof |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN107958213A (en) * | 2017-11-20 | 2018-04-24 | 北京工业大学 | A kind of cospace pattern based on the medical treatment of brain-computer interface recovering aid and deep learning method |
CN109620223A (en) * | 2018-12-07 | 2019-04-16 | 北京工业大学 | A kind of rehabilitation of stroke patients system brain-computer interface key technology method |
CN112370066A (en) * | 2020-09-30 | 2021-02-19 | 北京工业大学 | Brain-computer interface method of stroke rehabilitation system based on generation of countermeasure network |
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Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN107958213A (en) * | 2017-11-20 | 2018-04-24 | 北京工业大学 | A kind of cospace pattern based on the medical treatment of brain-computer interface recovering aid and deep learning method |
CN109620223A (en) * | 2018-12-07 | 2019-04-16 | 北京工业大学 | A kind of rehabilitation of stroke patients system brain-computer interface key technology method |
CN112370066A (en) * | 2020-09-30 | 2021-02-19 | 北京工业大学 | Brain-computer interface method of stroke rehabilitation system based on generation of countermeasure network |
Cited By (2)
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---|---|---|---|---|
CN114082169A (en) * | 2021-11-22 | 2022-02-25 | 江苏科技大学 | Disabled hand soft body rehabilitation robot motor imagery identification method based on electroencephalogram signals |
CN114664434A (en) * | 2022-03-28 | 2022-06-24 | 上海韶脑传感技术有限公司 | Cerebral apoplexy rehabilitation training system for different medical institutions and training method thereof |
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