CN107958213A - A kind of cospace pattern based on the medical treatment of brain-computer interface recovering aid and deep learning method - Google Patents

A kind of cospace pattern based on the medical treatment of brain-computer interface recovering aid and deep learning method Download PDF

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CN107958213A
CN107958213A CN201711159910.4A CN201711159910A CN107958213A CN 107958213 A CN107958213 A CN 107958213A CN 201711159910 A CN201711159910 A CN 201711159910A CN 107958213 A CN107958213 A CN 107958213A
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王卓峥
杜秀文
吴强
董英杰
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Hangzhou Xingyuan Intelligent Biotechnology Co ltd
Wang Zhuozheng
Beijing University of Technology
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Abstract

The present invention discloses a kind of cospace pattern based on the medical treatment of brain-computer interface recovering aid and deep learning method, comprises the following steps:Step 1:EEG signals pre-process, and obtain filtering out the EEG signals after noise;Step 2:Improved OVR CSP algorithms can carry out feature extraction to filtering out the multiclass Mental imagery EEG signal after noise, obtain the feature of every a kind of Mental imagery EEG signals, form one-dimensional characteristic data, while the input using variance as grader;Step 3:Further Feature Extraction is carried out using the improved CNN networks for adapting to one-dimensional input sample and is classified.Technical solution using the present invention, more accurately differentiates the movement position and limb motion state of patient, objective data supporting is provided for Measuring scale assessing sufferer rehabilitation degree.

Description

A kind of cospace pattern and deep learning based on the medical treatment of brain-computer interface recovering aid Method
Technical field
The invention belongs to rehabilitation nerve subject technology field, it is related to a kind of based on the medical treatment of brain-computer interface recovering aid Cospace pattern and deep learning method.
Background technology
Cerebral apoplexy (is commonly called as:Headstroke Stroke), it is due to that cerebral vessels rupture or because angiemphraxis causes blood suddenly It cannot flow into brain and cause a kind of common brain blood circulation disorder disease of brain tissue impairment.Due to its incidence compared with Height, has high disability rate, serious threat human health.American Heart Association (AHA) heart disease in 2016 is counted with palsy Data update shows that cerebral apoplexy is to be only second to cardiopathic global human Health Killer.And China's cerebral apoplexy incidence just Risen with annual 8.7% speed, illness rate and the death rate are only second to hypertension positioned at second, are brought to society and family heavy Stress and huge financial burden.
Currently from treatment means analyze, domestic and international rehabilitation of stroke patients system focus primarily on clinical rehabilitation training system with. Clinical rehabilitation training system uses the rehabilitation training based on neuro-physiology basis more, mainly according to motor development control principle With brain plasticity principle, using the nervimotion mechanism such as associated movement, synergistic effect and attitudinal reflex, by doctor to patient Clinical rehabilitation evaluation, judges the functional status and potential ability of patient, then " suits the remedy to the case ", carry out corresponding health Refreshment is practiced.Method at present clinically on cerebral apoplexy motor functional evaluation is very much, as skeleton symbol Fugl-Meyer motor functions are commented Point-score, Brunnstrom grade evaluation and test methods etc..The method of these Measuring scale assessings, all relies on the inspection and observation of doctor, belongs to Manually evaluation, although clinically widely using, evaluation result is easily influenced be subject to physiatrician's subjective factor, and scale score Level index is more, it is necessary to physiatrician participates in the overall process, and limited doctor's quantity in face of huge sufferer colony often power not from The heart, or even delay best occasion for the treatment.The present situation in China is clinical rehabilitation resource (such as physiatrician, therapist, nursing at present Personnel, bed etc.) it is more nervous, and there are serious regional imbalance, and for nervous system injury, medical field does not have also at present Have the ability to repair completely.The dyskinesia after being ill of stroke patient how is solved the problems, such as by initiative rehabilitation training, is current The research hotspot and difficult point of medicine.
Thus the help of research high-performance rehabilitation of stroke patients system brain-computer interface can not be complete by the patient of normal output channel Trained into initiative rehabilitation, so that improving motion function recovers normal activity behavior, for China's Treatment of Cerebral Stroke in neural subject There is highly important research significance and development prospect with facing Information Science crossing domain.
Existing medical research shows that most cerebral apoplexies, brain and limbs nerve pathway paralysed patient are undamaged, therefore BCI based on Mental imagery can be used for the stroke area for rebuilding damage, i.e. it is anti-using Mental imagery and nerve that BCI recovers function The impaired exercise control of feedback, the study that enhancing Motion Control Network is rebuild.
Wherein cospace pattern (Common Spatial Pattern, CSP) is proved to be one of most efficient method, its Other EEG signals being tested are incorporated into CSP learning processes by the thought of transfer learning, ensure that the brain telecommunications of subject The estimated bias of number covariance is preferable, is widely used in small training sample data.But with the increase of training sample, it is classified Accuracy rate increasess slowly;And with the rising of time complexity, the practical application of limit algorithm.
In recent years, go deep into the research of deep learning, many brain electricity sample datas can be incorporated into such as convolutional Neural Processing is trained in network frame, it is necessary to relatively great amount of training sample.The convolution number of plies can be chosen according to sample size, and one Denier sample size data are too small, cause identification error rate to greatly promote.For multiclass Mental imagery EEG signals, sample size is generally Small Amount, and quoting deep learning frame merely cannot train up, it is difficult to play the advantage of CNN algorithms.Therefore, it is of the invention It is proposed to classify the mode that improved CSP algorithms and CNN are combined to multiclass Mental imagery EEG signals.
In conclusion using the Mental imagery EEG signals of brain-computer interface technology identification patient, can be by patient motion wish Translate into control command and drive convalescence device action, help patient to complete initiative rehabilitation training, it is extensive to be conducive to improvement motor function Multiple effect, and do not tending to be ripe also using upper for the algorithm of this technology.
The content of the invention
The present invention provides a kind of cospace pattern based on the medical treatment of brain-computer interface recovering aid and deep learning method, for How the rehabilitation training field of study movement dysfunction, realize high accuracy, the brain based on Mental imagery of high robust Machine interfacing, so as to accurately differentiate athletic posture and the limb motion position of patient, carries for Measuring scale assessing sufferer rehabilitation degree For objective data supporting, effectively alleviate current Treatment of Cerebral Stroke equipment and doctor's resource wretched insufficiency, what subjective treatment zone was come The problems such as drawback.The pretreatment that EEG signals are carried out using wavelet package transforms and quick independent analytical methods is proposed, mainly Original Mental imagery EEG signals are filtered, the various noises being reduced as far as in EEG signals, improve signal-to-noise ratio, Based on improved cospace pattern combination convolutional neural networks algorithm identification patient motion imagination EEG signals, so that more accurately Differentiate the movement position and limb motion state of patient, objective data supporting is provided for Measuring scale assessing sufferer rehabilitation degree.
To achieve the above object, the present invention adopts the following technical scheme that:
A kind of cospace pattern based on the medical treatment of brain-computer interface recovering aid and deep learning method, comprise the following steps:
Step 1:EEG signals pre-process, and obtain filtering out the EEG signals after noise;
Step 2:Improved OVR-CSP algorithms can carry out feature to filtering out the multiclass Mental imagery EEG signal after noise Extraction, obtains the feature of every a kind of Mental imagery EEG signals, forms one-dimensional characteristic data, while using variance as grader Input;
Step 3:Further Feature Extraction is carried out using the improved CNN networks for adapting to one-dimensional input sample and is classified.
Preferably, step 1 specifically includes:Two processes of wavelet package transforms and Fast Independent Component Analysis:
WPT is carried out to original EEG first, determines the Decomposition order of WPT, it is suitable to be selected according to the characteristics of EEG and noise Wavelet basis function, finally determine to filter out frequency band where high-frequency noise, and to corresponding frequency band zero setting;
FastICA conversion is carried out to oneself signal after filtering out high-frequency noise again, FastICA inverse transformations and FastICA are inverse Conversion, obtains filtering out the EEG signals after noise.
Preferably, step 2 is specially:OVR-CSP is that five type games imagination task is divided into five two new classes to classify Problem, obtains five projection matrixes, and five groups of corresponding spatial features can be obtained after projection;
Specific calculating process is as follows:If Xi(i=1,2,3,4,5) is the N*T EEG signals of five generic tasks, and N believes for collection Number channel number, T be each passage sampling number, T >=N, the basic principle of OVR-CSP algorithms is to calculate five classes respectively The normalized covariance matrix R of datai, i.e.,:
Blending space covariance matrix R, which can be obtained, is:
Wherein,For the average covariance matrices of five generic task many experiments, characteristic value point is carried out to R Solution, obtains:
R=UVUT
Wherein, U is the feature vector of R, and V is the eigenvalue matrix of R;Descending arrangement is carried out to eigenvalue matrix, according to row Feature vector is made identical adjustment in position after sequence, then whitening matrix P is:
P=V-1/2UT
OVR-CSP is classified as one kind when calculating projection matrix, by one type, and remaining four class is then to be another kind of, i.e.,:
It is X respectively by two new classes are divided into by the EEG signals X of pretreatment1,X1', the projection under the i-th quasi-mode Direction is projected, and is obtained:
Z1=(U1′)TP1X1,Z1'=(U1′)TP1X1' (i=1,2,3,4,5)
The covariance matrix value of matrix of the five class data after projection is
The feature vector of covariance matrix is normalized again, is obtained:
Wherein, n be feature vector columns, in this, as feature vector into Row classification learning.
Preferably, step 3 is specially:For the CNN structures of Mental imagery eeg signal classification, MIEEGNet is named as Network structure, the network are formed by 5 layers, are input layer including first layer, two layers of convolutional layer, 1 layer of full articulamentum and 1 layer Softmax classification layers;Sample data size is 1*fi,j;Wherein, N is Mental imagery EEG through being obtained after OVR-CSP algorithm process The Characteristic Number arrived, fi,j=5*m;The second layer (C2) and third layer (C3) are all convolutional layer, to be carried out to input sample data Further Feature Extraction, the wherein second layer (C2 } there is i2A convolution kernel, the size of convolution kernel is 1*n2, third layer (C3) has i3A volume Product core, the size of convolution kernel is 1*n3;4th layer (F4) is full articulamentum, its by way of connecting entirely with layer 5 (O5) one Rise and form individual layer perceptron, by output category result after third layer (C3) output result treatment.
MIEEGNet networks are classified in last layer using Softmax functions, give input fi,jWhen, the input number According to be c classification probability be denoted as p (y=c | fi,j), then network losses function Loss is defined as follows,
Wherein, fi,jFor the Mental imagery feature training sample of input, i.e., the covariance matrix after OVR-CSP is normalized Feature vector;Y is the corresponding class label of sample (having determined that classification);f(fi,j) it is to be exported by the network of MIEEGNet; Then output layer starts the weights of convolution kernel in backpropagation adjustment network;Finally pass through the training of MIEEGNet, export Loss Value;f(fi,j) output be a left side, the right hand, tongue is left, the classification of right crus of diaphragm;And controlled the classification results of Mental imagery as BCI Pass down the line processed gives mechanical upper and lower extremities, as quantization assessment index.
Preferably, the network training includes two stages:
The propagated forward stage:From training sample set sample drawn fi,j, its corresponding class label is y, and x is input to this The MIEEGNet networks of Subject Design, the output of last layer are exactly the input of current layer, are calculated and worked as by activation primitive ReLU The output of front layer, then successively hands on.Finally by classification layer outputFor three-dimensional feature vector, its element represents Sample data fi,jBelong to the probability of classification c;
Back-propagation phase:Calculate the output of classification layerThe error of class label y is given with sample, and uses minimum The method adjustment weighting parameter of mean square error cost function.
Brief description of the drawings
Fig. 1 Technology Roadmaps proposed by the present invention
Fig. 2 brain computator method schematic diagrames proposed by the present invention based on Mental imagery.
The EEG signals WAVELET PACKET DECOMPOSITION schematic diagram of Fig. 3 present invention.
The pretreatment schematic diagram of the EEG signals of Fig. 4 present invention.
Fig. 5 FB(flow block)s of the present invention.
Fig. 6 MIEEGNet network structures proposed by the present invention.
Embodiment
As shown in Fig. 2, a kind of cospace pattern based on the medical treatment of brain-computer interface recovering aid of the invention and deep learning side Method, CSP is combined and is improved with two kinds of algorithms of CNN, and Mental imagery EEG signals are carried out with Further Feature Extraction and is divided Class.Compared with directly inputting original EEG signals, the discrimination between signal is not only increased, and makes CNN input sample numbers It is one-dimensional according to being fallen below by two dimension, input sample size of data is greatly reduced, reduces the number of convolution kernel in network, makes needs Trained network weight number substantially reduces.
As shown in Figure 1, a kind of cospace pattern based on the medical treatment of brain-computer interface recovering aid and deep learning method, including Following steps:
Step 1:EEG signals pre-process, including two processes of wavelet package transforms and Fast Independent Component Analysis:
First, WPT is carried out to original Mental imagery brain electric information, determines the Decomposition order of WPT, utilize wavelet package transforms When filtering out the high-frequency noise in EEG signals, it is contemplated that the enhancing of the power spectrum of characterization EEG signals ERD/ERS phenomenons or decrease Frequency range is mainly reflected in 8~30Hz, is that 128Hz can determine that the Decomposition order of WPT is five layers for sample frequency therefore, Determine frequency range in 8~30Hz by WAVELET PACKET DECOMPOSITION.Finally determine to filter out the frequency band where high-frequency noise, and to corresponding Frequency band zero setting, if Fig. 3 is WAVELET PACKET DECOMPOSITION schematic diagram.
Then, FastICA conversion then to oneself signal after filtering out high-frequency noise is carried out, obtains the EEG signals of each passage Independent element, then calculate the C3 of each independent element and original EEG signal respectively, the related coefficient of C4 passages, retains phase Relation number is higher than the independent element of the threshold value of setting, then FastICA inverse transformations, obtains filtering out the EEG signals after noise, such as Fig. 4 It is shown.Two kinds of algorithms of WPT and FastICA pre-process EEG signals, and the noise and part for having filtered out EEG signals disturb Signal, easy to follow-up feature extraction and classification.
Step 2:Feature extraction is carried out to multiclass Mental imagery EEG signal using OVR-CSP algorithms.
Assuming that the number for the projection matrix that W classes signal needs to try to achieve is W, W groups spatial domain knot is can obtain after each sample projection Fruit, which is the feature per a kind of Mental imagery EEG signals extracted, finally using variance as the defeated of grader Enter.Feature after extraction can form one-dimensional characteristic data.It enormously simplify convolutional neural networks structure:Both can increase each Discrimination between EEG signal, can also reduce the size of data of convolutional neural networks input sample.It is illustrated in figure 5 and is based on Five type games imagination task (being left hand, the right hand, foot and tongue respectively) feature extraction of OVR-CSP.
OVR-CSP is that five type games imagination task is divided into five two new class classification problems, obtains five projection matrixes, Five groups of corresponding spatial features can be obtained after projection.Specific calculating process is as follows:If Xi(i=1,2,3,4,5) appoint for five classes The N*T EEG signals of business, N be collection signal channel number, T be each passage sampling number, T >=N.OVR-CSP algorithms Basic principle be to calculate the normalized covariance matrix R of five class data respectivelyi, i.e.,:
Blending space covariance matrix R, which can be obtained, is:
WhereinFor the average covariance matrices of five generic task many experiments.Characteristic value point is carried out to R Solution, obtains:
R=UVUT
Wherein, U is the feature vector of R;V is the eigenvalue matrix of R.Descending arrangement is carried out to eigenvalue matrix, according to row Feature vector is made identical adjustment in position after sequence, then whitening matrix P is:
P=V-1/2UT
Unlike two classical class CSP algorithms, one type is classified as one by OVR-CSP when calculating projection matrix Class, and remaining four class is then to be another kind of, i.e.,:
It is X respectively by two new classes are divided into by the EEG signals X of pretreatment1,X1', the projection under the i-th quasi-mode Direction is projected, and is obtained:
Z1=(U1′)TP1X1,Z1'=(U1′)TP1X1' (i=1,2,3,4,5)
The covariance matrix value of matrix of the five class data after projection is RZi=ZiZi T(i=1,2,3,4,5), then to association The feature vector of variance matrix is normalized, and obtains:
(n is the columns of feature vector)
Classification learning is carried out in this, as feature vector.
Step 3:Further Feature Extraction is carried out using the improved CNN networks for adapting to one-dimensional input sample and is classified.
The present invention devises a kind of CNN structures for Mental imagery eeg signal classification, is named as MIEEGNet networks Structure, CNN network structures such as Fig. 6.The network is formed by 5 layers, is input layer including first layer, two layers of convolutional layer, 1 layer it is complete Articulamentum and 1 layer of Softmax classification layer.Sample data size is 1*fi,j.Wherein, N is Mental imagery EEG through OVR-CSP algorithms Handle the Characteristic Number obtained afterwards, fi,j=5*m;The second layer (C2) and third layer (C3) are all convolutional layer, to inputting sample Notebook data progress Further Feature Extraction, the wherein second layer (C2 } there is i2A convolution kernel, the size of convolution kernel is 1*n2, third layer (C3) there is i3A convolution kernel, the size of convolution kernel is 1*n3.Since input sample data length is less than normal, so CNN networks of the present invention Down-sampled layer is saved, ReLU function optimization parameters is used in convolutional layer, avoids " gradient disappearance ";4th layer (F4) is full connection Layer, it forms individual layer perceptron by way of connecting entirely together with layer 5 (O5), and third layer (C3) is exported result treatment Output category result afterwards.
MIEEGNet networks are classified in last layer using Softmax functions.The given input f of the present inventioni,jWhen, should Input data be c classification probability be denoted as p (y=c | fi,j), then network losses function Loss is defined as follows,
Wherein fi,jFor the Mental imagery feature training sample of input, i.e., the covariance matrix after OVR-CSP is normalized Feature vector;Y is the corresponding class label of sample (having determined that classification);f(fi,j) it is to be exported by the network of MIEEGNet.So Output layer starts the weights of convolution kernel in backpropagation adjustment network afterwards.Finally pass through the training of MIEEGNet, export Loss's Value, the value of Loss is smaller, illustrates that training effect is better, classification results are more accurate.f(fi,j) output for a left side, the right hand, tongue, A left side, the classification of right crus of diaphragm.And mechanical upper and lower extremities are communicated to using the classification results of Mental imagery as BCI control commands, as quantization Deliberated index.Compared to only with the experience deliberated index of doctor, there is provided objective data supporting, feeds back to physiatrician.Rehabilitation Doctor carries out constantly renewal evaluation and test model again, and then as the new method of guiding treatment, is carried out for patients with cerebral apoplexy effective Rehabilitation training, until helping patient's early recovery.
The number of filter of each layer traditional of CNN and its modified network is all fixed constant, but and not all filter Ripple device, which can select the other implicit features of target class, to be come.Since the number and number of filter of CNN network parameters are close Correlation, therefore in back-propagation phase, can be according to that minimizes mean square error cost function and adaptively adjust each layer of wave filter Number (convolution kernel number), so as to reduce algorithm complex while accuracy of identification is ensured.This problem introduces convolution kernel number and becomes K is measured, convolutional layer C2, C3 are respectively adopted 2kWith 2k+1A convolution kernel carries out convolution operation to every layer of input.
Activation primitive of the sigmoid functions as convolutional network, this hair are used in traditional CNN network characterization mapping structures Bright use instead corrects linear unit (Rectified Linear Units, ReLU) function to possess the network after training appropriate dilute Property is dredged, while the issuable gradient of conventional activation function during backpropagation arameter optimization can be solved well disappears to ask Topic, accelerates the convergence of network.
Network structure proposed by the present invention realizes the mapping relations for being input to output, efficiently solves due to traditional convolution The gradient disappearance problem of neutral net.
Wherein network training includes two stages:The propagated forward stage.From training sample set sample drawn fi,j, it is corresponded to Class label be y.X is input to the MIEEGNet networks of this Subject Design, the output of last layer is exactly the input of current layer. The output of current layer is calculated by activation primitive ReLU, is then successively handed on.Finally by classification layer output For three-dimensional feature vector, its element representative sample data fi,jBelong to the probability of classification c.Back-propagation phase.Calculate classification layer OutputThe error of class label y is given with sample, and is joined using the method adjustment weights for minimizing mean square error cost function Number.
During scalp EEG signals EEG feature extractions, signal decomposition is by the thought present invention introduces patches Small data slot, forms covariance matrix, then by Matrix Estimation extraction Mental imagery EEG signals based on OVR-CSP side The characteristic of division vector of method;After high dimensional feature DUAL PROBLEMS OF VECTOR MAPPING to lower dimensional space, according to minimum mean square error cost function certainly Adapt to adjust traditional each layer of convolution kernel number of CNN, and the convergence corrected linear unit function using using and accelerate network, Improve classification effectiveness.
In conclusion the present invention has made the improvement of cospace pattern and convolutional neural networks based on Mental imagery, i.e., gram It is bad in more classification task expression effects traditional C/S P algorithms are taken, and overcome single use convolutional neural networks to need largely The two, is cleverly combined by the shortcomings that data sample, and robustness is preferable on small sample in processes.In view of both at home and abroad to brain The mode of Stroke Rehabilitation treatment is more single.Therefore the rehabilitation training field applied to dyskinesia patient, helps patient Initiative rehabilitation training is participated in, is conducive to improve motor function recovery effect, it is objective to provide for Measuring scale assessing sufferer rehabilitation degree Data supporting.

Claims (5)

1. a kind of cospace pattern based on the medical treatment of brain-computer interface recovering aid and deep learning method, it is characterised in that including Following steps:
Step 1:EEG signals pre-process, and obtain filtering out the EEG signals after noise;
Step 2:Improved OVR-CSP algorithms can carry out feature extraction to filtering out the multiclass Mental imagery EEG signal after noise, The feature of every a kind of Mental imagery EEG signals is obtained, forms one-dimensional characteristic data, while using variance as the defeated of grader Enter;
Step 3:Further Feature Extraction is carried out using the improved CNN networks for adapting to one-dimensional input sample and is classified.
2. cospace pattern and deep learning method as claimed in claim 1 based on the medical treatment of brain-computer interface recovering aid, its It is characterized in that, step 1 specifically includes:Two processes of wavelet package transforms and Fast Independent Component Analysis:
WPT is carried out to original EEG first, determines the Decomposition order of WPT, is selected according to the characteristics of EEG and noise suitable small Ripple basic function, finally determines to filter out the frequency band where high-frequency noise, and to corresponding frequency band zero setting;
FastICA conversion, FastICA inverse transformations and FastICA inverse transformations are carried out to oneself signal after filtering out high-frequency noise again, Obtain filtering out the EEG signals after noise.
3. cospace pattern and deep learning method as claimed in claim 2 based on the medical treatment of brain-computer interface recovering aid, its It is characterized in that step 2 is specially:OVR-CSP is that five type games imagination task is divided into five two new class classification problems, is obtained Five projection matrixes, can obtain five groups of corresponding spatial features after projection;
Specific calculating process is as follows:If Xi(i=1,2,3,4,5) is the N*T EEG signals of five generic tasks, and N is the logical of collection signal Road number, T are the sampling number of each passage, and T >=N, the basic principle of OVR-CSP algorithms is to calculate five class data respectively Normalized covariance matrix Ri, i.e.,:
<mrow> <msub> <mi>R</mi> <mi>i</mi> </msub> <mo>=</mo> <mfrac> <mrow> <msub> <mi>X</mi> <mi>i</mi> </msub> <msup> <msub> <mi>X</mi> <mi>i</mi> </msub> <mi>T</mi> </msup> </mrow> <mrow> <mi>t</mi> <mi>r</mi> <mi>a</mi> <mi>c</mi> <mi>e</mi> <mrow> <mo>(</mo> <msub> <mi>X</mi> <mi>i</mi> </msub> <msup> <msub> <mi>X</mi> <mi>i</mi> </msub> <mi>T</mi> </msup> <mo>)</mo> </mrow> </mrow> </mfrac> <mo>,</mo> <mi>i</mi> <mo>=</mo> <mn>1</mn> <mo>,</mo> <mn>2</mn> <mo>,</mo> <mn>3</mn> <mo>,</mo> <mn>4</mn> <mo>,</mo> <mn>5</mn> </mrow>
Blending space covariance matrix R, which can be obtained, is:
<mrow> <mi>R</mi> <mo>=</mo> <mover> <msub> <mi>R</mi> <mn>1</mn> </msub> <mo>&amp;OverBar;</mo> </mover> <mo>+</mo> <mover> <msub> <mi>R</mi> <mn>2</mn> </msub> <mo>&amp;OverBar;</mo> </mover> <mo>+</mo> <mover> <msub> <mi>R</mi> <mn>3</mn> </msub> <mo>&amp;OverBar;</mo> </mover> <mo>+</mo> <mover> <msub> <mi>R</mi> <mn>4</mn> </msub> <mo>&amp;OverBar;</mo> </mover> <mo>+</mo> <mover> <msub> <mi>R</mi> <mn>5</mn> </msub> <mo>&amp;OverBar;</mo> </mover> </mrow>
Wherein,For the average covariance matrices of five generic task many experiments, Eigenvalues Decomposition is carried out to R, :
R=UVUT
Wherein, U is the feature vector of R, and V is the eigenvalue matrix of R;Descending arrangement is carried out to eigenvalue matrix, after sequence Position make identical adjustment to feature vector, then whitening matrix P is:
P=V-1/2UT
OVR-CSP is classified as one kind when calculating projection matrix, by one type, and remaining four class is then to be another kind of, i.e.,:
<mrow> <msup> <msub> <mi>R</mi> <mn>1</mn> </msub> <mo>&amp;prime;</mo> </msup> <mo>=</mo> <mover> <msub> <mi>R</mi> <mn>2</mn> </msub> <mo>&amp;OverBar;</mo> </mover> <mo>+</mo> <mover> <msub> <mi>R</mi> <mn>3</mn> </msub> <mo>&amp;OverBar;</mo> </mover> <mo>+</mo> <mover> <msub> <mi>R</mi> <mn>4</mn> </msub> <mo>&amp;OverBar;</mo> </mover> <mo>+</mo> <mover> <msub> <mi>R</mi> <mn>5</mn> </msub> <mo>&amp;OverBar;</mo> </mover> </mrow>
It is X respectively by two new classes are divided into by the EEG signals X of pretreatment1,X1', the projecting direction under the i-th quasi-mode Projected, obtained:
Z1=(U1′)TP1X1,Z1'=(U1′)TP1X1' (i=1,2,3,4,5)
The covariance matrix value of matrix of the five class data after projection is
The feature vector of covariance matrix is normalized again, is obtained:
Wherein, n is the columns of feature vector, is divided in this, as feature vector Class learns.
4. cospace pattern and deep learning method as claimed in claim 3 based on the medical treatment of brain-computer interface recovering aid, its It is characterized in that step 3 is specially:For the CNN structures of Mental imagery eeg signal classification, MIEEGNet network structures are named as, The network is formed by 5 layers, is input layer including first layer, and two layers of convolutional layer, 1 layer of full articulamentum and 1 layer of Softmax classify Layer;Sample data size is 1*fi,j;Wherein, N is the Mental imagery EEG features through being obtained after OVR-CSP algorithm process Number, fi,j=5*m;The second layer (C2) and third layer (C3) are all convolutional layer, are carried to carry out quadratic character to input sample data Take, wherein the second layer (C2 } have i2A convolution kernel, the size of convolution kernel is 1*n2, third layer (C3) has i3A convolution kernel, convolution kernel Size be 1*n3;4th layer (F4) is full articulamentum, it forms individual layer by way of connecting entirely with together with layer 5 (O5) Perceptron, by output category result after third layer (C3) output result treatment.
MIEEGNet networks are classified in last layer using Softmax functions, give input fi,jWhen, which is c The probability of classification be denoted as p (y=c | fi,j), then network losses function Loss is defined as follows,
<mrow> <mi>L</mi> <mi>o</mi> <mi>s</mi> <mi>s</mi> <mrow> <mo>(</mo> <mi>f</mi> <mo>(</mo> <msub> <mi>f</mi> <mrow> <mi>i</mi> <mo>,</mo> <mi>j</mi> </mrow> </msub> <mo>)</mo> <mo>,</mo> <mi>y</mi> <mo>)</mo> </mrow> <mo>=</mo> <mo>-</mo> <msub> <mi>&amp;Sigma;</mi> <mi>c</mi> </msub> <mi>log</mi> <mi>p</mi> <mrow> <mo>(</mo> <mi>y</mi> <mo>=</mo> <mi>c</mi> <mo>|</mo> <msub> <mi>f</mi> <mrow> <mi>i</mi> <mo>,</mo> <mi>j</mi> </mrow> </msub> <mo>)</mo> </mrow> <mo>=</mo> <mo>-</mo> <mi>log</mi> <mi>p</mi> <mrow> <mo>(</mo> <mi>y</mi> <mo>=</mo> <mover> <mi>y</mi> <mo>~</mo> </mover> <mo>|</mo> <mi>x</mi> <mo>)</mo> </mrow> </mrow>
Wherein, fi,jFor the Mental imagery feature training sample of input, i.e., the spy of covariance matrix after OVR-CSP is normalized Sign vector;Y is the corresponding class label of sample (having determined that classification);f(fi,j) it is to be exported by the network of MIEEGNet;Then Output layer starts the weights of convolution kernel in backpropagation adjustment network;Finally pass through the training of MIEEGNet, export the value of Loss; f(fi,j) output be a left side, the right hand, tongue is left, the classification of right crus of diaphragm;And the classification results of Mental imagery are controlled as BCI and are ordered Order is communicated to mechanical upper and lower extremities, as quantization assessment index.
5. cospace pattern and deep learning method as claimed in claim 4 based on the medical treatment of brain-computer interface recovering aid, its It is characterized in that, the network training includes two stages:
The propagated forward stage:From training sample set sample drawn fi,j, its corresponding class label is y, and x is input to this problem The MIEEGNet networks of design, the output of last layer are exactly the input of current layer, and current layer is calculated by activation primitive ReLU Output, then successively hand on.Finally by classification layer output For three-dimensional feature vector, its element representative sample number According to fi,jBelong to the probability of classification c;
Back-propagation phase:Calculate the output of classification layerThe error of class label y is given with sample, and it is square using minimizing The method adjustment weighting parameter of error cost function.
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Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109003680A (en) * 2018-09-28 2018-12-14 四川大学 Epilepsy data statistical approach and device
CN109009092A (en) * 2018-06-15 2018-12-18 东华大学 A method of removal EEG signals noise artefact
CN109009097A (en) * 2018-07-18 2018-12-18 厦门大学 A kind of brain electricity classification method of adaptive different sample frequencys
CN109144266A (en) * 2018-08-29 2019-01-04 安徽大学 A kind of brain-computer interface lead optimization method based on independent component analysis
CN109164910A (en) * 2018-07-05 2019-01-08 北京航空航天大学合肥创新研究院 For the multiple signals neural network architecture design method of electroencephalogram
CN109325586A (en) * 2018-12-05 2019-02-12 北京航空航天大学合肥创新研究院 Deep neural network system based on composite object function
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
CN109685031A (en) * 2018-12-29 2019-04-26 河海大学常州校区 A kind of brain-computer interface midbrain signal characteristics classification method and system
CN109726751A (en) * 2018-12-21 2019-05-07 北京工业大学 Method based on depth convolutional neural networks identification brain Electrical imaging figure
CN110188836A (en) * 2019-06-21 2019-08-30 西安交通大学 A kind of brain function network class method based on variation self-encoding encoder
CN110569727A (en) * 2019-08-06 2019-12-13 华南理工大学 Transfer learning method combining intra-class distance and inter-class distance based on motor imagery classification
CN110851783A (en) * 2019-11-12 2020-02-28 华中科技大学 Heterogeneous label space migration learning method for brain-computer interface calibration
CN111544856A (en) * 2020-04-30 2020-08-18 天津大学 Brain-myoelectricity intelligent full limb rehabilitation method based on novel transfer learning model
CN111990992A (en) * 2020-09-03 2020-11-27 山东中科先进技术研究院有限公司 Electroencephalogram-based autonomous movement intention identification method and system
CN112185558A (en) * 2020-09-22 2021-01-05 珠海中科先进技术研究院有限公司 Mental health and rehabilitation evaluation method, device and medium based on deep learning
CN113128384A (en) * 2021-04-01 2021-07-16 北京工业大学 Brain-computer interface software key technical method of stroke rehabilitation system based on deep learning

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104771163A (en) * 2015-01-30 2015-07-15 杭州电子科技大学 Electroencephalogram feature extraction method based on CSP and R-CSP algorithms

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104771163A (en) * 2015-01-30 2015-07-15 杭州电子科技大学 Electroencephalogram feature extraction method based on CSP and R-CSP algorithms

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
曾庆山: ""基于CSP与卷积神经网络算法的多类运动"", 《科学技术与工程》 *
王洪涛: ""混合脑机接口实现及其应用研究"", 《中国博士学位论文全文数据库 医药卫生科技辑》 *
范明莉: ""基于卷积神经网络的运动想象脑电信号特征提取与分类"", 《中国优秀硕士学位论文全文数据库 医药卫生科技辑》 *

Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109009092B (en) * 2018-06-15 2020-06-02 东华大学 Method for removing noise artifact of electroencephalogram signal
CN109009092A (en) * 2018-06-15 2018-12-18 东华大学 A method of removal EEG signals noise artefact
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