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Objective:To improve the users’ comfort of steady-state visual evoked potential (SSVEP)-based brain-computer interface (BCI) through high-frequency stimulation and overcome the problem of accuracy decline caused by high frequency by combining dual-frequency encoding.Methods:Two dual-frequency high-frequency 60-instruction paradigms based on left and right visual fields and checkerboard stimuli were designed based on the 25.5 - 39.6 Hz frequency. Thirteen subjects participated in the experiment, and spectrum and spatial characteristics analyses were performed on SSVEP signals. The filter bank parameters were optimized based on the spectrum characteristics. Extended canonical correlation analysis (eCCA), ensemble task-related component analysis (eTRCA), and task-discriminant component analysis (TDCA) were used for SSVEP recognition.Results:Stable SSVEP was successfully induced in both the left and right visual fields and the checkerboard grid paradigm. The left and right visual fields had high signal-to-noise ratios for the fundamental frequency and its harmonics and weak signal-to-noise ratios for intermodulation components, whereas the intermodulation components of the 2 stimulus frequencies of the checkerboard grid, f1 + f2, had significantly higher signal-to-noise ratios than the second harmonic components above 30 Hz, and there was also a f2 ? f1 component and a 2 f1 ? f2 component. Combined with brain topography, it can be seen that the f1 and f2 response components of the left and right visual fields are located on opposite sides of the visual field, while the checkerboard grids are both concentrated in the center of the occipital region. Regarding the lateralization of brain topography amplitude and signal-to-noise ratio, the mean values of the PO3 and PO4 signal-to-noise ratios at the stimulation frequency of the left and right visual fields are consistent with the contralateral response characteristics. The 5 fb ? 1 method is the optimal filter set setting method, and the recognition correctness rate of TDCA for the left and right visual fields is the highest. However, the comparison of the recognition correctness rate of tessellated lattice eTRCA and TDCA is not statistically significant ( P > 0.05). The information transmission rates of the three algorithms all increase and then decrease with the increase in data length. Conclusions:The designed dual-frequency, high-frequency SSVEP-BCI paradigm is able to better balance performance and comfort and provides a basis for practical large instruction set BCI design methods.
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The gallbladder is the most common site of tumor occurrence among biliary tract cancer. Gallbladder cancer accounts for approximately 0.6% of new cancers and 0.9% of cancer-related deaths. The risk factors identified for the development of gallbladder cancer include being female,>65 years of age, asymptomatic gallstone disease,and obesity. Surgical resection is the only curative treatment for early-stage gallbladder cancer, and some intermediate or advanced gallbladder cancers can be radically cured by extended resection. However, the extent of liver resection or lymph node dissection and whether to combine it with bile duct removal, revascularisation,and multiple organ resection remain somewhat controversial. After neoadjuvant treatment, up to a third of patients with locally advanced gallbladder cancer benefit from secondary surgical treatment. Only a small proportion of patients with gallbladder cancer at high risk for recurrence will benefit from postoperative adjuvant therapy. With the advent of different target-targeted drugs and the use of genetic tests in biliary tract cancer, targeted therapy and PD-1/PD-L1 inhibitors may become the new standard of care for gallbladder cancer and need to be further explored.
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In recent years, HIV infection prevalence in MSM has been in increase in China. HIV testing is the only way to identify HIV-infection, effectively curb the spread of HIV and reduce AIDS-related death risks. At present, the situation of HIV testing in MSM is not satisfactory, and expanding HIV testing is the one of the key measures for AIDS prevention and control in this population. This paper summarizes the role and strategies of expanding HIV testing in MSM in order to provide a reference for the improvement of HIV testing in this population.
Subject(s)
Male , Humans , HIV Infections/epidemiology , Homosexuality, Male , Acquired Immunodeficiency Syndrome , Risk-Taking , Sexual and Gender Minorities , HIV Testing , China/epidemiologyABSTRACT
There are few researches on the modulation effect of transcranial direct current stimulation(tDCS) on complex spatial cognition. Especially, the influence of tDCS on the neural electrophysiological response in spatial cognition is not yet clear. This study selected the classic spatial cognition task paradigm (three-dimensional mental rotation task) as the research object. By comparing the changes in behavior and event-related potentials in different modes of tDCS before, during and after the application of tDCS, this study analyzed the behavioral and neurophysiological effects of tDCS on mental rotation. The comparison between active-tDCS and sham-tDCS showed no statistically significant difference in behavior between different stimulation modes. Still, the changes in the amplitudes of P2 and P3 during the stimulation were statistically significant. Compared with sham-tDCS, the amplitudes of P2 and P3 in active-tDCS mode showed a greater decrease during the stimulation. This study clarifies the influence of tDCS on the event-related potentials of the mental rotation task. It shows that tDCS may improve the brain information processing efficiency during the mental rotation task. Also, this study provides a reference for an in-depth understanding and exploration of the modulation effect of tDCS on complex spatial cognition.
Subject(s)
Transcranial Direct Current Stimulation , Cognition , Evoked Potentials , BrainABSTRACT
High-frequency steady-state asymmetric visual evoked potential (SSaVEP) provides a new paradigm for designing comfortable and practical brain-computer interface (BCI) systems. However, due to the weak amplitude and strong noise of high-frequency signals, it is of great significance to study how to enhance their signal features. In this study, a 30 Hz high-frequency visual stimulus was used, and the peripheral visual field was equally divided into eight annular sectors. Eight kinds of annular sector pairs were selected based on the mapping relationship of visual space onto the primary visual cortex (V1), and three phases (in-phase[0º, 0º], anti-phase [0º, 180º], and anti-phase [180º, 0º]) were designed for each annular sector pair to explore response intensity and signal-to-noise ratio under phase modulation. A total of 8 healthy subjects were recruited in the experiment. The results showed that three annular sector pairs exhibited significant differences in SSaVEP features under phase modulation at 30 Hz high-frequency stimulation. And the spatial feature analysis showed that the two types of features of the annular sector pair in the lower visual field were significantly higher than those in the upper visual field. This study further used the filter bank and ensemble task-related component analysis to calculate the classification accuracy of annular sector pairs under three-phase modulations, and the average accuracy was up to 91.5%, which proved that the phase-modulated SSaVEP features could be used to encode high- frequency SSaVEP. In summary, the results of this study provide new ideas for enhancing the features of high-frequency SSaVEP signals and expanding the instruction set of the traditional steady state visual evoked potential paradigm.
Subject(s)
Humans , Evoked Potentials, Visual , Brain-Computer Interfaces , Healthy Volunteers , Signal-To-Noise RatioABSTRACT
Steady-state visual evoked potential (SSVEP) has been widely used in the research of brain-computer interface (BCI) system in recent years. The advantages of SSVEP-BCI system include high classification accuracy, fast information transform rate and strong anti-interference ability. Most of the traditional researches induce SSVEP responses in low and middle frequency bands as control signals. However, SSVEP in this frequency band may cause visual fatigue and even induce epilepsy in subjects. In contrast, high-frequency SSVEP-BCI provides a more comfortable and natural interaction despite its lower amplitude and weaker response. Therefore, it has been widely concerned by researchers in recent years. This paper summarized and analyzed the related research of high-frequency SSVEP-BCI in the past ten years from the aspects of paradigm and algorithm. Finally, the application prospect and development direction of high-frequency SSVEP were discussed and prospected.
Subject(s)
Humans , Brain-Computer Interfaces , Evoked Potentials, Visual , AlgorithmsABSTRACT
Two new ursane triterpenoids along with twelve known compounds were isolated from 80% ethanol extract of Agastache rugosa (Fisch. et. Mey.) O. Kuntze by using silica gel column, MCI column, ODS column and HPLC. The structures of the new compounds were identified as 2α,3α-dihydroxy-24-nor-urs-4(23),12(13)-dien-28-oic acid (1) and 2α,3α-dihydroxy-24-nor-urs-4(23),12(13),20(30) -trien-28-oic acid (2) by HR-ESI-MS, NMR and ECD spectral data, named agasursacid A and agasursacid B. In addition, compounds 3, 4, 6, 8 showed anti-coxsackievirus B3 (CVB3) activities with a IC50 as 4.77, 1.59, 11.11 and 25.87 μmol·L-1, resepectively.
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Three new anthraquinones were isolated from the 80% ethanol extract of Prismatomeris tetrandra by silica gel, MCI, ODS column chromatography and high performance preparative liquid chromatography (HPLC). The structures of the new compounds were identified by mass spectrometry, nuclear magnetic resonance and other spectroscopic methods as 6-hydroxy-1,2,3-trimethoxy-7-methylanthracene-9,10-dione (1), 6-(hydroxymethyl)-1,2,3-trimethoxyanthracene-9,10-dione (2) and 7-hydroxy-6-(hydroxymethyl)-1,2-dimethoxyanthracene-9,10-dione (3). Compounds 1, 2 and 3 showed protective effects against monosodium glutamate-induced damage in SH-SY5Y neuroblastoma cells, with the cell survival rates elevated 18.45%, 4.31%, and 7.65%, respectively.
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Purpose@#This study aimed to evaluate the diagnostic value of combined fine-needle aspiration (FNA) with core needle biopsy (CNB) in thyroid nodules. @*Methods@#FNA and CNB were performed simultaneously on 703 nodules. We compared the proportions of inconclusive results and the diagnostic performance for malignancy among FNA, CNB, and combined FNA/CNB for different nodule sizes. @*Results@#Combined FNA/CNB showed lower proportions of inconclusive results than CNB for all nodules (2.8% vs. 5.7%, P1.0 cm (2.0% vs. 5.0 %, P1.5 cm (2.1% vs. 3.9 %, P=0.016). The sensitivity of combined FNA/CNB in predicting malignancy was significantly higher than that of CNB (89.0% vs. 80.0%, P1.5 cm, the difference between combined FNA/CNB and CNB was not significant (84.2% vs. 78.9%, P=0.500). @*Conclusion@#Regardless of nodule size, combined FNA/CNB tended to yield lower proportions of inconclusive results than CNB or FNA alone and exhibited higher performance in diagnosing malignancy. The combined FNA/CNB technique may be a more valuable diagnostic method for nodules ≤1.5 cm and nodules with a risk of malignancy than CNB and FNA alone.
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@#Objective - To analyze the relationship between cobalt level of post shift urine and individual exposure level of ， cobalt and its compounds in cobalt exposed workers and to explore the feasibility of using urine cobalt as a biomarker. Methods - A total of 148 occupational cobalt exposed workers from a new material company were selected as the exposed ， - - group and 44 non occupational cobalt exposed workers from the company were selected as the control group using the typical sampling method. The exposure concentration of time weighted average of cobalt and its compounds in the workplace air of the - two groups was determined by inductively coupled plasma mass spectrometry as the individual exposure level. The cobalt levels - - of pre shift and post shift urinary samples of the two groups were detected by this method. The linear relationship between the - cobalt level of post shift urine and the individual exposure level of cobalt and its compounds in the air of the workplace was Results - 3 analyzed. The individual exposure level of cobalt and its compounds in the exposed group was 1.10 131.71 μg/m with （M） 3 the median of 12.23 μg/m. No cobalt and its compounds were detected in the workplace air in the control group. The cobalt - - levels of pre shift and post shift urines in exposed group were higher than those in the control group at the same time point （M： vs ， vs ， P ） - - 1.54 0.56 μg/L 8.77 0.83 μg/L all <0.01 . The cobalt level of post shift urine was higher than that in pre shift （M： vs ，P ）， urine in the exposed group 8.77 1.54 μg/L <0.01 and it was positively correlated with the individual exposure level （ ，P ） ， of cobalt and its compounds Spearman correlation coefficient=0.86 <0.01 . After common logarithm conversion the linear regression equation of the cobalt level of post shift urine and the common logarithm of individual exposure level of cobalt and （x） ：ŷ x（ ；F ， its compounds in the exposed group was as follows = −0.178 + 0.988 coefficient of determination=0.72 =374.75 P ；t ， P ） Conclusion - <0.01 = - 19.36 <0.01 . There was a linear correlation between cobalt level of post shift urine and occupational cobalt exposure level of cobalt exposed workers. Urinary cobalt can be used as a biomarker of occupational cobalt
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Objective: To explore the association between occupational noise exposure and cardiovascular disease (CVD) risk in a large Chinese population. Methods: In December 2019, the study included 21412 retired participants from the Dongfeng-Tongji Cohort Study at baseline from September 2008 to June 2010, occupational noise exposure was evaluated through workplace noise level and/or the job titles. In a subsample of 8931 subjects, bilateral hearing loss was defined as a pure-tone mean of 25 dB or higher at 0.5, 1 , 2, and 4 kHz in both ears. Logistic regression models were used to explore the association of occupational noise exposure, bilateral hearing loss with 10-year CVD risk. Results: Compared with participants without occupational noise exposure, the 10-year CVD risk was significantly higher for noise exposure duration ≥20 years (OR=1.20, 95%CI:1.01-1.41 , P=0.001) after adjusting for potential confounders. In the sex-specific analysis, the association was only statistically significant in males (OR=2.34, 95%CI: 1.18-4.66, P<0.001) , but not in females (OR=1.15, 95%CI:0.97-1.37, P=0.153). In the subsample analyses, bilateral hearing loss, which was an indicator for exposure to loud noise, was also associated with a higher risk of 10-year CVD (OR= 1.17, 95% CI:1.05-1.44, P <0.001) , especially for participants who were males (OR =1.24, 95% CI:1.07-2.30, P<0.001) , aged equal and over 60 years old (OR=2.30, 95%CI: 1.84-2.88, P<0.001) , and exposed to occupational noise (OR=1.66, 95%CI: 1.02-2.70, P=0.001). Conclusion: Occupational noise exposure may be a risk factor for CVD.
Subject(s)
Aged , Female , Humans , Male , Middle Aged , Cardiovascular Diseases/epidemiology , Cohort Studies , Hearing Loss, Bilateral/complications , Hearing Loss, Noise-Induced/epidemiology , Noise, Occupational/adverse effects , Occupational Diseases/epidemiology , Occupational Exposure/adverse effectsABSTRACT
ObjectiveTo study the effect of icariin on the proliferative capacity of hepatocellular carcinoma cell line CLC5 and the underlying mechanism. MethodThe targets of icariin were screened out by network pharmacology， and the target network and protein-protein interaction （PPI） network were constructed to predict the possible targets and pathways of icariin. CCK-8 assay was employed to explore the effects of different concentrations （0， 6.25， 12.5， 25， 50 μmol·L-1） of icariin on the viability of CLC5 cells. Further， CLC5 cells were treated with 0， 25， 50 μmol·L-1 icariin， and the effect of icariin on CLC5 cell proliferation was examined by Edu-488 assay and clone formation assay （CFA）. Western blot was employed to measure the expression levels of proteins in the protein kinase B （Akt）/glycogen synthase kinase 3β （GSK3β）/cell cycle-dependent kinase （CDK） pathway in the CLC5 cells exposed to different concentrations of icariin. ResultNetwork pharmacological analysis revealed that icariin may inhibit the hepatocellular carcinoma via cell cycle arrest and inhibition of tumor cell proliferation. Compared with the blank group， icariin decreased the viability of CLC5 cells in a time- and concentration-dependent manner （P<0.01） and reduced the positive rate of Edu-488 and the colonies in CFA （P<0.05， P<0.01）. Moreover， icariin down-regulated the protein levels of p-Akt， p-GSK3β， CDK4， and CyclinD1 （P<0.05， P<0.01）. ConclusionIcariin may block cell cycle to suppress the proliferation of CLC5 cells via inhibiting the Akt/GSK3β/CDK pathway.
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Objective@#To investigate routine blood test results and secular changes among Tibetan children and adolescents aged from 3 to 19 in the plateau, and to provide the basis for reference range of routine blood test for this population.@*Methods@#A total of 1 568 Tibetan children and adolescents aged from 3 to 19 living in Shigatse, Tibet were selected by cluster random sampling method. Routine blood test results and its secular trends were compared by age and gender.@*Results@#Significantly differences were found in red blood cell(RBC), hemoglobin(HGB), hematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular hemoglobin(MCH), white blood cell(WBC), neutrophil(NEU), neutrophil percentage (NEU%), lymphocyte(LYM), lymphocyte percentage(LYM%)，monocyte percentage(MON%)，eosinophil percentage(EOS%),basophil percentage(BAS%) and platelet(PLT) among the four age groups of 3-5, 6-12, 13-15, and 16-19 years ( F/H =60.22, 179.41, 249.45, 115.03, 74.90, 14.33 , 33.46, 78.90, 49.20, 97.29, 24.45,24.28,42.65,20.10, P <0.05). Among red blood cell indexes, RBC, HGB, HCT,MCH increased with age in boys( F =148.77, 493.04, 623.14, 249.92, P <0.05), but there was no similar trend in girls( F =1.37, 0.15, 2.94, 0.11, P >0.05). HCT showed significant sex differences among the four age groups of 3-5 years, 6-12 years, 13-15 years, and 16-19 years [(41.33±2.31)% vs (41.98±2.40)%; (43.28±2.60)% vs ( 43.75 ±2.36)%; (46.20±3.11)% vs (44.83±2.67)%; (51.10±4.15)% vs (43.61±4.70)%, t =-2.10, -2.88, 3.50, 10.82, P <0.05]. WBC, NEU, NEU%, LYM, LYM%, monocyte(MON), and MON% increased significantly with age in both boys and girls ( P <0.05). From the age of 12 to 13, RBC, HGB and HCT in Tibetan male and female adolescents showed an opposite trend and widened gradually.@*Conclusion@#Red blood cell index shows significantly different trends among Tibetan adolescents and children of different ages and genders. Regional nationality, age, gender, and other factors should be considered when developing the reference value range of blood routine index.
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Objective@#To investigate routine blood test results and secular changes among Tibetan children and adolescents aged from 3 to 19 in the plateau, and to provide the basis for reference range of routine blood test for this population.@*Methods@#A total of 1 568 Tibetan children and adolescents aged from 3 to 19 living in Shigatse, Tibet were selected by cluster random sampling method. Routine blood test results and its secular trends were compared by age and gender.@*Results@#Significantly differences were found in red blood cell(RBC), hemoglobin(HGB), hematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular hemoglobin(MCH), white blood cell(WBC), neutrophil(NEU), neutrophil percentage (NEU%), lymphocyte(LYM), lymphocyte percentage(LYM%)，monocyte percentage(MON%)，eosinophil percentage(EOS%),basophil percentage(BAS%) and platelet(PLT) among the four age groups of 3-5, 6-12, 13-15, and 16-19 years ( F/H =60.22, 179.41, 249.45, 115.03, 74.90, 14.33 , 33.46, 78.90, 49.20, 97.29, 24.45,24.28,42.65,20.10, P <0.05). Among red blood cell indexes, RBC, HGB, HCT,MCH increased with age in boys( F =148.77, 493.04, 623.14, 249.92, P <0.05), but there was no similar trend in girls( F =1.37, 0.15, 2.94, 0.11, P >0.05). HCT showed significant sex differences among the four age groups of 3-5 years, 6-12 years, 13-15 years, and 16-19 years [(41.33±2.31)% vs (41.98±2.40)%; (43.28±2.60)% vs ( 43.75 ±2.36)%; (46.20±3.11)% vs (44.83±2.67)%; (51.10±4.15)% vs (43.61±4.70)%, t =-2.10, -2.88, 3.50, 10.82, P <0.05]. WBC, NEU, NEU%, LYM, LYM%, monocyte(MON), and MON% increased significantly with age in both boys and girls ( P <0.05). From the age of 12 to 13, RBC, HGB and HCT in Tibetan male and female adolescents showed an opposite trend and widened gradually.@*Conclusion@#Red blood cell index shows significantly different trends among Tibetan adolescents and children of different ages and genders. Regional nationality, age, gender, and other factors should be considered when developing the reference value range of blood routine index.
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italic>Psidium guajava Linn. is an evergreen shrub or small tree of Psidium Linnaeus in the Myrtaceae family. One new glycoside (1) together with 3 known meroterpenoids (2-4) and 9 known glycosides (5-13) were isolated from the fruits of Psidium guajava Linn.. The structure of the new compound was elucidated by the spectroscopic data analysis of HR-ESIMS, 1D- and 2D-NMR, and it was named psiguaoside A (1). The known compounds were identified as guajadial (2), 4,5-diepipsidial A (3), psidial A (4), chrysin-8-C-β-D-glucoside (5), 2,6-dihydroxy-3,5-dimethyl-4-O-β-D-glucopyranosyl-benzophenone (6), quercetin-3-O-β-D-glucopyranoside (7), quercetin-3-O-xyloside (8), guaijaverin (9), avicularin (10), guavinoside E (11), guavinoside B (12), guajaphenone A (13). In the bioactivity assay, compound 3 exhibited significant inhibitory activitiy of U87 with IC50 values of 8.379 μmol·L-1.
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Two new labdane diterpenoids were isolated from 95% ethanol extract of the leaves of Callicarpa formosana Rolfe by using silica gel column, MCI column, ODS column and HPLC. Their structures were elucidated by HR-ESI-MS, NMR and ECD spectral data. All of them are new compounds, named 13E-6β-hydroxylabda-8(17),13-dien-15-oic acid (1) and 13E-7α-hydroxylabda-8(17),13-dien-15-oic acid (2). Compounds 1 and 2 were tested for antioxidant activity, and none of them had obvious activity.
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Brain-computer interface (BCI) systems based on steady-state visual evoked potential (SSVEP) have become one of the major paradigms in BCI research due to their high signal-to-noise ratio and short training time required by users. Fast and accurate decoding of SSVEP features is a crucial step in SSVEP-BCI research. However, the current researches lack a systematic overview of SSVEP decoding algorithms and analyses of the connections and differences between them, so it is difficult for researchers to choose the optimum algorithm under different situations. To address this problem, this paper focuses on the progress of SSVEP decoding algorithms in recent years and divides them into two categories-trained and non-trained-based on whether training data are needed. This paper also explains the fundamental theories and application scopes of decoding algorithms such as canonical correlation analysis (CCA), task-related component analysis (TRCA) and the extended algorithms, concludes the commonly used strategies for processing decoding algorithms, and discusses the challenges and opportunities in this field in the end.
Subject(s)
Algorithms , Brain-Computer Interfaces , Electroencephalography , Evoked Potentials, Visual , Photic StimulationABSTRACT
OBJECTIVES@#To investigate the distribution of genotypes of thalassemia in children in Guangxi, China.@*METHODS@#A total of 30 417 children with positive results of thalassemia screening in the Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region from January 2011 to December 2019 were enrolled. Single-tube multiplex PCR, agarose gel electrophoresis, and reverse dot blot hybridization technique were used for the detection of common α- and β-thalassemia genes. Gap-PCR or gene sequence analysis was performed for 2 703 children suspected of rare thalassemia.@*RESULTS@#Among the 30 417 children with positive results of thalassemia screening, 23 214 (76.32%) were diagnosed with thalassemia, and the detection rates of α-thalassemia, β-thalassemia, and α-thalassemia with β-thalassemia were 47.77%, 23.75%, and 4.80% respectively. A total of 13 types of α-thalassemia alleles (18 480 alleles in total) were detected, mainly --@*CONCLUSIONS@#There are diverse gene mutations and rich genotypes of thalassemia among children in Guangxi, and α-thalassemia is more common, with --
Subject(s)
Child , Humans , China/epidemiology , Genotype , Heterozygote , Mutation , alpha-Thalassemia/genetics , beta-Thalassemia/geneticsABSTRACT
Error self-detection based on error-related potentials (ErrP) is promising to improve the practicability of brain-computer interface systems. But the single trial recognition of ErrP is still a challenge that hinters the development of this technology. To assess the performance of different algorithms on decoding ErrP, this paper test four kinds of linear discriminant analysis algorithms, two kinds of support vector machines, logistic regression, and discriminative canonical pattern matching (DCPM) on two open accessed datasets. All algorithms were evaluated by their classification accuracies and their generalization ability on different sizes of training sets. The study results show that DCPM has the best performance. This study shows a comprehensive comparison of different algorithms on ErrP classification, which could give guidance for the selection of ErrP algorithm.
Subject(s)
Algorithms , Brain , Brain-Computer Interfaces , Discriminant Analysis , Electroencephalography , Support Vector MachineABSTRACT
As the most common active brain-computer interaction paradigm, motor imagery brain-computer interface (MI-BCI) suffers from the bottleneck problems of small instruction set and low accuracy, and its information transmission rate (ITR) and practical application are severely limited. In this study, we designed 6-class imagination actions, collected electroencephalogram (EEG) signals from 19 subjects, and studied the effect of collaborative brain-computer interface (cBCI) collaboration strategy on MI-BCI classification performance, the effects of changes in different group sizes and fusion strategies on group multi-classification performance are compared. The results showed that the most suitable group size was 4 people, and the best fusion strategy was decision fusion. In this condition, the classification accuracy of the group reached 77%, which was higher than that of the feature fusion strategy under the same group size (77.31%