As an important component of the event related potential (ERP), late positive potential (LPP) is an ideal component for studying emotion regulation. This study was focused on processing and analysing the LPP component of the emotional cognitive reappraisal electroencephalogram (EEG) signal. Firstly, we used independent component analysis (ICA) algorithm to remove electrooculogram, electromyogram and some other artifacts based on 16 subjects' EEG data by using EGI 64-channal EEG acquisition system. Secondly, we processed feature extraction of the EEG signal at Pz electrode by using one versus the rest common spatial patterns (OVR-CSP) algorithm. Finally, the extracted LPP component was analysed both in time domain and spatial domain. The results indicated that ① From the perspective of amplitude comparison, the LPP amplitude, which was induced by cognitive reappraisal, was much higher than the amplitude under the condition of watching neural stimuli, but lower than the amplitude under condition of watching negative stimuli; ② from the perspective of time process, the difference between cognitive reappraisal and watching after processing with OVR-CSP algorithm was in the process of range between 0.3 s and 1.5 s; but the difference between cognitive reappraisal and watching after processing with averaging method was during the process between 0.3 s and 1.25 s. The results suggested that OVR-CSP algorithm could not only accurately extract the LPP component with fewer trials compared with averaging method so that it provided a better method for the follow-up study of cognitive reappraisal strategy, but also provide neurophysiological basis for cognitive reappraisal in emotional regulation.
Scaffold is one of the key elements required for tissue engineering. Porous scaffolds have several special advantages for muscle tissue engineering, and they are beneficial to cell survival, myogenic differentiation, and vascular ingrowth. The performance of porous scaffolds is closely related to the property of the biomaterials used. Additionally, the pore size and porosity may affect cell adhesion, proliferation, and differentiation. This review focuses on the application of porous scaffolds in muscle tissue engineering, including their categories, application, and advantages.
This paper aims to assist the individual clinical diagnosis of children with attention-deficit/hyperactivity disorder using electroencephalogram signal detection method. Firstly, in our experiments, we obtained and studied the electroencephalogram signals from fourteen attention-deficit/hyperactivity disorder children and sixteen typically developing children during the classic interference control task of Simon-spatial Stroop, and we completed electroencephalogram data preprocessing including filtering, segmentation, removal of artifacts and so on. Secondly, we selected the subset electroencephalogram electrodes using principal component analysis (PCA) method, and we collected the common channels of the optimal electrodes which occurrence rates were more than 90% in each kind of stimulation. We then extracted the latency (200~450 ms) mean amplitude features of the common electrodes. Finally, we used the k-nearest neighbor (KNN) classifier based on Euclidean distance and the support vector machine (SVM) classifier based on radial basis kernel function to classify. From the experiment, at the same kind of interference control task, the attention-deficit/hyperactivity disorder children showed lower correct response rates and longer reaction time. The N2 emerged in prefrontal cortex while P2 presented in the inferior parietal area when all kinds of stimuli demonstrated. Meanwhile, the children with attention-deficit/hyperactivity disorder exhibited markedly reduced N2 and P2 amplitude compared to typically developing children. KNN resulted in better classification accuracy than SVM classifier, and the best classification rate was 89.29% in StI task. The results showed that the electroencephalogram signals were different in the brain regions of prefrontal cortex and inferior parietal cortex between attention-deficit/hyperactivity disorder and typically developing children during the interference control task, which provided a scientific basis for the clinical diagnosis of attention-deficit/hyperactivity disorder individuals.