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Motor imagery training induces changes in brain neural networks in stroke patients 被引量:15
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作者 Fang Li Tong Zhang +3 位作者 Bing-Jie Li Wei Zhang Jun Zhao Lu-Ping Song 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第10期1771-1781,共11页
Motor imagery is the mental representation of an action without overt movement or muscle activation. However, the effects of motor imagery on stroke-induced hand dysfunction and brain neural networks are still unknown... Motor imagery is the mental representation of an action without overt movement or muscle activation. However, the effects of motor imagery on stroke-induced hand dysfunction and brain neural networks are still unknown. We conducted a randomized controlled trial in the China Rehabilitation Research Center. Twenty stroke patients, including 13 males and 7 females, 32–51 years old, were recruited and randomly assigned to the traditional rehabilitation treatment group(PP group, n = 10) or the motor imagery training combined with traditional rehabilitation treatment group(MP group, n = 10). All patients received rehabilitation training once a day, 45 minutes per session, five times per week, for 4 consecutive weeks. In the MP group, motor imagery training was performed for 45 minutes after traditional rehabilitation training, daily. Action Research Arm Test and the Fugl-Meyer Assessment of the upper extremity were used to evaluate hand functions before and after treatment. Transcranial magnetic stimulation was used to analyze motor evoked potentials in the affected extremity. Diffusion tensor imaging was used to assess changes in brain neural networks. Compared with the PP group, the MP group showed better recovery of hand function, higher amplitude of the motor evoked potential in the abductor pollicis brevis, greater fractional anisotropy of the right dorsal pathway, and an increase in the fractional anisotropy of the bilateral dorsal pathway. Our findings indicate that 4 weeks of motor imagery training combined with traditional rehabilitation treatment improves hand function in stroke patients by enhancing the dorsal pathway. This trial has been registered with the Chinese Clinical Trial Registry(registration number: Chi CTR-OCH-12002238). 展开更多
关键词 nerve regeneration STROKE hand function motor imagery brain neural network motion evoked potential dorsal pathway ventral pathway diffusion tensor imaging neural regeneration
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An Adapted Convolutional Neural Network for Brain Tumor Detection
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作者 Kamagaté Beman Hamidja Kanga Koffi +2 位作者 Brou Pacôme Olivier Asseu Souleymane Oumtanaga 《Open Journal of Applied Sciences》 2024年第10期2809-2825,共17页
In medical imaging, particularly for analyzing brain tumor MRIs, the expertise of skilled neurosurgeons or radiologists is often essential. However, many developing countries face a significant shortage of these speci... In medical imaging, particularly for analyzing brain tumor MRIs, the expertise of skilled neurosurgeons or radiologists is often essential. However, many developing countries face a significant shortage of these specialists, which impedes the accurate identification and analysis of tumors. This shortage exacerbates the challenge of delivering precise and timely diagnoses and delays the production of comprehensive MRI reports. Such delays can critically affect treatment outcomes, especially for conditions requiring immediate intervention, potentially leading to higher mortality rates. In this study, we introduced an adapted convolutional neural network designed to automate brain tumor diagnosis. Our model features fewer layers, each optimized with carefully selected hyperparameters. As a result, it significantly reduced both execution time and memory usage compared to other models. Specifically, its execution time was 10 times shorter than that of the referenced models, and its memory consumption was 3 times lower than that of ResNet. In terms of accuracy, our model outperformed all other architectures presented in the study, except for ResNet, which showed similar performance with an accuracy of around 90%. 展开更多
关键词 brain Tumor MRI Convolutional neural network KKDNet GoogLeNet DensNet ResNet ShuffleNet
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Prediction of malignancy selective neural networks degree in brain glioma using ensemble 被引量:1
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作者 刘天羽 李国正 吴耿锋 《Journal of Shanghai University(English Edition)》 CAS 2006年第3期244-246,共3页
A clustering algorithm based selective neural networks ensemble (CLUSEN) is proposed to predict the degree of malignancy in brain glioma. Since the degree prediction of malignancy is critical before brain surgery, m... A clustering algorithm based selective neural networks ensemble (CLUSEN) is proposed to predict the degree of malignancy in brain glioma. Since the degree prediction of malignancy is critical before brain surgery, many learning methods are used like rule induction algorithm, single neural networks, support vector machines, etc. Ensemble learning methods can improve the generalization of single learning machine, and are becoming popular in the machine learning and medical data processing communities. The procedure of CLUSEN can efficiently remove redundancy learning individuals and help improve the diversity of ensemble methods. CLUSEN is used to predict the degree of malignancy in brain glioma. Experimental results on a set of brain glioma data show that, compared to support vector machines, rule induction and single neural networks, the classification accuracy of CLUSEN is higher. 展开更多
关键词 ensemble learning neural networks brain glioma clustering algorithm.
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Application of Convolutional Neural Networks in Classification of GBM for Enhanced Prognosis
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作者 Rithik Samanthula 《Advances in Bioscience and Biotechnology》 CAS 2024年第2期91-99,共9页
The lethal brain tumor “Glioblastoma” has the propensity to grow over time. To improve patient outcomes, it is essential to classify GBM accurately and promptly in order to provide a focused and individualized treat... The lethal brain tumor “Glioblastoma” has the propensity to grow over time. To improve patient outcomes, it is essential to classify GBM accurately and promptly in order to provide a focused and individualized treatment plan. Despite this, deep learning methods, particularly Convolutional Neural Networks (CNNs), have demonstrated a high level of accuracy in a myriad of medical image analysis applications as a result of recent technical breakthroughs. The overall aim of the research is to investigate how CNNs can be used to classify GBMs using data from medical imaging, to improve prognosis precision and effectiveness. This research study will demonstrate a suggested methodology that makes use of the CNN architecture and is trained using a database of MRI pictures with this tumor. The constructed model will be assessed based on its overall performance. Extensive experiments and comparisons with conventional machine learning techniques and existing classification methods will also be made. It will be crucial to emphasize the possibility of early and accurate prediction in a clinical workflow because it can have a big impact on treatment planning and patient outcomes. The paramount objective is to not only address the classification challenge but also to outline a clear pathway towards enhancing prognosis precision and treatment effectiveness. 展开更多
关键词 GLIOBLASTOMA Machine Learning Artificial Intelligence neural networks brain Tumor Cancer Tensorflow LAYERS CYTOARCHITECTURE Deep Learning Deep neural network Training Batches
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Modulatory effects of acupuncture on brain networks in mild cognitive impairment patients 被引量:42
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作者 Ting-ting Tan Dan Wang +10 位作者 Ju-ke Huang Xiao-mei Zhou Xu Yuan Jiu-ping Liang Liang Yin Hong-liang Xie Xin-yan Jia Jiao Shi Fang Wang Hao-bo Yang Shang-jie Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第2期250-258,共9页
Functional magnetic resonance imaging has been widely used to investigate the effects of acupuncture on neural activity. However, most functional magnetic resonance imaging studies have focused on acute changes in bra... Functional magnetic resonance imaging has been widely used to investigate the effects of acupuncture on neural activity. However, most functional magnetic resonance imaging studies have focused on acute changes in brain activation induced by acupuncture. Thus, the time course of the therapeutic effects of acupuncture remains unclear. In this study, 32 patients with amnestic mild cognitive impairment were randomly divided into two groups, where they received either Tiaoshen Yizhi acupuncture or sham acupoint acupuncture. The needles were either twirled at Tiaoshen Yizhi acupoints, including Sishencong(EX-HN1), Yintang(EX-HN3), Neiguan(PC6), Taixi(KI3), Fenglong(ST40), and Taichong(LR3), or at related sham acupoints at a depth of approximately 15 mm, an angle of ± 60°, and a rate of approximately 120 times per minute. Acupuncture was conducted for 4 consecutive weeks, five times per week, on weekdays. Resting-state functional magnetic resonance imaging indicated that connections between cognition-related regions such as the insula, dorsolateral prefrontal cortex, hippocampus, thalamus, inferior parietal lobule, and anterior cingulate cortex increased after acupuncture at Tiaoshen Yizhi acupoints. The insula, dorsolateral prefrontal cortex, and hippocampus acted as central brain hubs. Patients in the Tiaoshen Yizhi group exhibited improved cognitive performance after acupuncture. In the sham acupoint acupuncture group, connections between brain regions were dispersed, and we found no differences in cognitive function following the treatment. These results indicate that acupuncture at Tiaoshen Yizhi acupoints can regulate brain networks by increasing connectivity between cognition-related regions, thereby improving cognitive function in patients with mild cognitive impairment. 展开更多
关键词 nerve regeneration mild cognitive impairment Alzheimer's disease neuroimaging resting-state functional magnetic resonance imaging brain network acupuncture Tiaoshen Yizhi neural regeneration
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The development of brain functional connectivity networks revealed by resting-state functional magnetic resonance imaging 被引量:3
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作者 Chao-Lin Li Yan-Jun Deng +2 位作者 Yu-Hui He Hong-Chang Zhai Fu-Cang Jia 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第8期1419-1429,共11页
Previous studies on brain functional connectivity networks in children have mainly focused on changes in function in specific brain regions, as opposed to whole brain connectivity in healthy children. By analyzing the... Previous studies on brain functional connectivity networks in children have mainly focused on changes in function in specific brain regions, as opposed to whole brain connectivity in healthy children. By analyzing the independent components of activation and network connectivity between brain regions, we examined brain activity status and development trends in children aged 3 and 5 years. These data could provide a reference for brain function rehabilitation in children with illness or abnormal function. We acquired functional magnetic resonance images from 15 3-year-old children and 15 5-year-old children under natural sleep cond让ions. The participants were recruited from five kindergartens in the Nanshan District of Shenzhen City, China. The parents of the participants signed an informed consent form with the premise that they had been fully informed regarding the experimental protocol. We used masked independent component analysis and BrainNet Viewer software to explore the independent components of the brain and correlation connections between brain regions. We identified seven independent components in the two groups of children, including the executive control network, the dorsal attention network, the default mode network, the left frontoparietal network, the right frontoparietal network, the salience network, and the motor network. In the default mode network, the posterior cingulate cortex, medial frontal gyrus, and inferior parietal lobule were activated in both 3- and 5-year-old children, supporting the "three-brain region theory” of the default mode network. In the frontoparietal network, the frontal and parietal gyri were activated in the two groups of children, and functional connectivity was strengthened in 5-year-olds compared with 3-year-olds, although the nodes and network connections were not yet mature. The high-correlation network connections in the default mode networks and dorsal attention networks had been significantly strengthened in 5-year-olds vs. 3-year-olds. Further, the salience network in the 3-year-old children included an activated insula/inferior frontal gyrus-anterior cingulate cortex network circu让 and an activated thalamus-parahippocampal-posterior cingulate cortex-subcortical regions network circuit. By the age of 5 years, no des and high-correlation network connections (edges) were reduced in the salience network. Overall, activation of the dorsal attention network, default mode network, left frontoparietal network, and right frontoparietal network increased (the volume of activation increased, the signals strengthened, and the high-correlation connections increased and strengthened) in 5-year-olds compared with 3-year-olds, but activation in some brain nodes weakened or disappeared in the salience network, and the network connections (edges) were reduced. Between the ages of 3 and 5 years, we observed a tendency for function in some brain regions to be strengthened and for the generalization of activation to be reduced, indicating that specialization begins to develop at this time. The study protocol was approved by the local ethics committee of the Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences in China with approval No. SIAT-IRB- 131115-H0075 on November 15, 2013. 展开更多
关键词 nerve REGENERATION FUNCTIONAL MRI brain network FUNCTIONAL connectivity RESTING-STATE ICA brain development children RESTING-STATE networkS INFANT template standardized neural REGENERATION
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基于通道自注意图卷积网络的运动想象脑电分类实验 被引量:1
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作者 孟明 张帅斌 +2 位作者 高云园 佘青山 范影乐 《实验技术与管理》 北大核心 2025年第2期73-80,共8页
该文将运动想象脑电分类任务设计成应用型教学实验。针对传统图卷积网络(graph convolutional neural networks,GCN)无法建模脑电通道间动态关系问题,提出一种融合通道注意机制的多层图卷积网络模型(channel self-attention multilayer ... 该文将运动想象脑电分类任务设计成应用型教学实验。针对传统图卷积网络(graph convolutional neural networks,GCN)无法建模脑电通道间动态关系问题,提出一种融合通道注意机制的多层图卷积网络模型(channel self-attention multilayer GCN,CAMGCN)。首先,CAMGCN计算脑电信号各个通道间的皮尔逊相关系数进行图建模,并通过通道位置编码模块学习通道间关系。然后将得到的时域和频域特征分量通过通道自注意图嵌入模块进行图嵌入,得到图数据。最后通过多级GCN模块提取并融合多层次拓扑信息,得出分类结果。CAMGCN深化了模型在自适应学习通道间动态关系的能力,并在结构方面提高了自注意机制与图数据的适配性。该模型在BCI Competition-Ⅳ2a数据集上的准确率达到83.8%,能够有效实现对运动想象任务的分类。该实验有助于增进学生对于深度学习和脑机接口的理解,培养创新思维,提高科研素质。 展开更多
关键词 脑机接口 脑电图 图卷积网络 注意力机制
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基于卷积和Transformer神经网络架构搜索的脑胶质瘤多组织分割网络 被引量:1
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作者 陶永鹏 柏诗淇 周正文 《计算机应用》 北大核心 2025年第7期2378-2386,共9页
脑胶质瘤在磁共振成像(MRI)图像中的形状大小变化大、边界模糊且组织结构复杂,这些特点导致了脑肿瘤分割任务的挑战性,通常这种任务需要具备深厚专业知识的研究人员设计复杂定制的网络模型才能完成。这一过程不仅耗时,而且需要大量的人... 脑胶质瘤在磁共振成像(MRI)图像中的形状大小变化大、边界模糊且组织结构复杂,这些特点导致了脑肿瘤分割任务的挑战性,通常这种任务需要具备深厚专业知识的研究人员设计复杂定制的网络模型才能完成。这一过程不仅耗时,而且需要大量的人力资源。为了简化网络设计流程并自动获取最优的网络结构,提出一种基于卷积和Transformer神经网络架构搜索的脑胶质瘤多组织分割网络(NASCT-Net),以在构建用于多模态MRI脑肿瘤分割的网络架构的过程中,提高分割的精确度。首先,将神经架构搜索(NAS)技术应用于编码器的构建,形成可堆叠的NAS编解码模块,以自动优化适用于脑胶质瘤精准分割的网络架构;其次,在编码器底层集成基于Transformer的特征编码模块,以增强对肿瘤各组之间的相对位置和全局信息的表征能力;最后,通过构建体积加权Dice损失函数(VWDiceLoss),解决前景与背景的不平衡问题。在BraTS2019脑肿瘤数据集上与Swin-Unet等方法进行比较的实验结果表明,NASCT-Net的平均Dice相似系数(DSC)提高了0.009,同时平均Hausdorff距离(HD)降低了1.831 mm,验证了NASCT-Net在提高脑肿瘤多组织分割精度方面的有效性。 展开更多
关键词 网络架构 神经网络架构搜索 脑肿瘤分割 卷积神经网络 TRANSFORMER
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Changes in brain functional network connectivity after stroke 被引量:5
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作者 Wei Li Yapeng Li +1 位作者 Wenzhen Zhu Xi Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第1期51-60,共10页
Studies have shown that functional network connection models can be used to study brain net- work changes in patients with schizophrenia. In this study, we inferred that these models could also be used to explore func... Studies have shown that functional network connection models can be used to study brain net- work changes in patients with schizophrenia. In this study, we inferred that these models could also be used to explore functional network connectivity changes in stroke patients. We used independent component analysis to find the motor areas of stroke patients, which is a novel way to determine these areas. In this study, we collected functional magnetic resonance imaging datasets from healthy controls and right-handed stroke patients following their first ever stroke. Using independent component analysis, six spatially independent components highly correlat- ed to the experimental paradigm were extracted. Then, the functional network connectivity of both patients and controls was established to observe the differences between them. The results showed that there were 11 connections in the model in the stroke patients, while there were only four connections in the healthy controls. Further analysis found that some damaged connections may be compensated for by new indirect connections or circuits produced after stroke. These connections may have a direct correlation with the degree of stroke rehabilitation. Our findings suggest that functional network connectivity in stroke patients is more complex than that in hea- lthy controls, and that there is a compensation loop in the functional network following stroke. This implies that functional network reorganization plays a very important role in the process of rehabilitation after stroke. 展开更多
关键词 nerve regeneration brain injury STROKE motor areas functional magnetic resonanceimaging brain network independent component analysis functional network connectivity neuralplasticity NSFC grant neural regeneration
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Performance comparison of three artificial neural network methods for classification of electroencephalograph signals of five mental tasks
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作者 Vijay Khare Jayashree Santhosh +1 位作者 Sneh Anand Manvir Bhatia 《Journal of Biomedical Science and Engineering》 2010年第2期200-205,共6页
In this paper, performance of three classifiers for classification of five mental tasks were investigated. Wavelet Packet Transform (WPT) was used for feature extraction of the relevant frequency bands from raw Electr... In this paper, performance of three classifiers for classification of five mental tasks were investigated. Wavelet Packet Transform (WPT) was used for feature extraction of the relevant frequency bands from raw Electroencephalograph (EEG) signal. The three classifiers namely used were Multilayer Back propagation Neural Network, Support Vector Machine and Radial Basis Function Neural Network. In MLP-BP NN five training methods used were a) Gradient Descent Back Propagation b) Levenberg-Marquardt c) Resilient Back Propagation d) Conjugate Learning Gradient Back Propagation and e) Gradient Descent Back Propagation with movementum. 展开更多
关键词 ELECTROENCEPHALOGRAM (EEG) Wavelet Packet Transform (WPT) Support Vector Machine (SVM) Radial Basis Function neural network (RBFNN) Multilayer Back Propagation neural network (MLP-BPNN) brain Computer Interface (BCI)
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基于改进卷积神经网络的SSVEP解析算法
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作者 杨建利 赵松磊 +2 位作者 刘凤双 杨晓茹 张烁 《河北大学学报(自然科学版)》 北大核心 2025年第5期530-540,共11页
稳态视觉诱发电位(steady-state visual evoked potentials,SSVEP)是脑机接口中常用的一种方式,该方式通常存在时域和频域信息利用不充分,导致信号解析不精准、不及时的问题.为此,本文提出了一种改进卷积神经网络模型的SSVEP解析算法.... 稳态视觉诱发电位(steady-state visual evoked potentials,SSVEP)是脑机接口中常用的一种方式,该方式通常存在时域和频域信息利用不充分,导致信号解析不精准、不及时的问题.为此,本文提出了一种改进卷积神经网络模型的SSVEP解析算法.设计了多通道输入模型,以多个频带滤波的信号作为输入,利用并行的时间注意力模块和多频带组合模块分别提取时域和频域的深度特征,经分类模块的多特征域融合分析实现了SSVEP信号的精准解析.在2个公共数据集上对本文算法进行了验证,分别取得了98.14%和82.72%的分类准确率.实验结果表明,该模型具有较高性能和鲁棒性,有助于推动基于SSVEP的脑机接口发展. 展开更多
关键词 卷积神经网络 脑机接口 稳态视觉诱发电位
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青少年吸烟者结构脑网络的可控性分析 被引量:1
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作者 丁静静 董芳 +6 位作者 王宏德 袁凯 程永欣 王娟 马宇欣 薛婷 喻大华 《生物化学与生物物理进展》 北大核心 2025年第1期182-193,共12页
目的基于控制和脑网络理论来探讨青少年吸烟者结构脑网络的可控性变化,考察可控性指标是否可以作为预测青少年吸烟者睡眠情况的有力因子。方法在内蒙古科技大学筛选出50例青少年吸烟者和51例健康对照者。基于弥散张量成像(DTI)构建每例... 目的基于控制和脑网络理论来探讨青少年吸烟者结构脑网络的可控性变化,考察可控性指标是否可以作为预测青少年吸烟者睡眠情况的有力因子。方法在内蒙古科技大学筛选出50例青少年吸烟者和51例健康对照者。基于弥散张量成像(DTI)构建每例受试者的基于各项异分数(FA)加权矩阵的结构脑网络。依据控制和脑网络理论计算平均可控性和模态可控性。采用双样本t检验进行组间差异比较,采用Pearson相关性分析对存在组间差异脑区的平均可控性和模态可控性与Fagerström尼古丁依赖测试(FTND)进行相关性分析。选取可控性得分在前10%的节点作为超级控制器,最后采用反向传播(backPropagation,BP)神经网络来预测青少年吸烟者的匹兹堡睡眠质量指数(PSQI)。结果吸烟组的背外侧额上回、辅助运动区、豆状核壳、豆状苍白球脑区的平均可控性,以及眶部额下回、辅助运动区、回直肌、后扣带回的模态可控性,均与健康对照组有显著性差异(P<0.05);吸烟组右侧辅助运动区(SMA.R)的平均可控性与FTND呈正相关(r=0.3801,P=0.0065),模态可控性与FTND呈负相关(r=0.3292,P=0.0196);利用可控性指标预测青少年PSQI睡眠指数时,平均可控性的预测效果(R=0.72281)要优于模态可控性的预测效果(R=0.60226)。结论青少年吸烟者结构脑网络的可控性存在异常,其可控性指标可以有效预测其睡眠情况,可为评估其认知功能损伤提供影像依据。 展开更多
关键词 青少年吸烟者 结构脑网络 可控性 反向传播神经网络
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基于迁移学习和改进EfficientNet-B0的脑肿瘤分类算法
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作者 王勇 杨义龙 +2 位作者 范晓晖 周雷 孔祥勇 《电子科技》 2025年第4期46-51,共6页
针对现有脑肿瘤分类模型和方法复杂度高以及识别率低等问题,文中提出一种基于改进EfficientNet-B0的模型用于3种脑肿瘤分类。在数据预处理阶段,使用ROI(Region of Interest)特征裁剪出脑肿瘤图像的关键特征区域,并按肿瘤类型扩增数据集... 针对现有脑肿瘤分类模型和方法复杂度高以及识别率低等问题,文中提出一种基于改进EfficientNet-B0的模型用于3种脑肿瘤分类。在数据预处理阶段,使用ROI(Region of Interest)特征裁剪出脑肿瘤图像的关键特征区域,并按肿瘤类型扩增数据集。根据卷积网络设计思想重新设计了EfficientNet中的MBConv(Mobile Inverted Bottleneck Convolution)模块,在首步卷积后引入卷积注意力CBAM(Convolutional Block Attention Module)。为了更完整地进行迁移学习,在不修改原始输出结构的基础上外接3个神经元用于脑肿瘤的三分类。改进网络模型具有更低的复杂度,可更好地适应肿瘤病灶的识别。文中利用迁移学习方法在公开数据集figshare-Brain Tumor Dataset上进行微调。实验结果表明,改进模型在该公共数据集上分类准确率为99.67%,相较于原始EfficientNet-B0网络提升了约3.1百分点。 展开更多
关键词 脑肿瘤分类 深度学习 卷积神经网络 阈值化处理 类平衡 EfficientNet ECA注意力机制 CBAM注意力机制
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重性抑郁障碍快感缺失的磁共振成像与神经生物学机制研究进展 被引量:1
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作者 黄佩姗 王克 +2 位作者 张雪琳 苗懿 董强利 《中国神经精神疾病杂志》 北大核心 2025年第3期180-185,共6页
重性抑郁障碍的核心症状之一是快感缺失,表现为个体对愉悦刺激的反应能力下降。伴快感缺失的重性抑郁障碍患者脑影像表现出一定特点,如纹状体、颞叶等脑区体积或皮质厚度减少,脑白质束微观结构改变,额叶、颞叶和边缘系统的神经元活动异... 重性抑郁障碍的核心症状之一是快感缺失,表现为个体对愉悦刺激的反应能力下降。伴快感缺失的重性抑郁障碍患者脑影像表现出一定特点,如纹状体、颞叶等脑区体积或皮质厚度减少,脑白质束微观结构改变,额叶、颞叶和边缘系统的神经元活动异常,默认模式网络、奖赏网络和额顶叶网络的连接性改变等。此外,压力应激、基因表达、谷氨酸系统及生物节律等因素也可能对快感缺失产生影响。快感缺失的神经生物学机制复杂多样,对重性抑郁障碍的诊断、治疗和预后具有重要指导意义。 展开更多
关键词 快感缺失 重性抑郁障碍 磁共振成像 脑结构 脑功能 脑网络 奖赏网络 神经机制
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头针治疗缺血性脑卒中后吞咽障碍的机制研究概况 被引量:1
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作者 杨晨 王东岩 +4 位作者 董旭 周以皓 张虹岩 杨思宇 李东霞 《环球中医药》 2025年第3期609-614,共6页
吞咽障碍是缺血性脑卒中后常见并发症之一,头针疗法在治疗缺血性脑卒中及其并发症方面疗效确切。本文对近年来国内外头针治疗缺血性脑卒中后吞咽障碍的机制研究进行总结,归纳发现头针作用机制如下:(1)上调血管内皮生长因子、缺氧诱导因... 吞咽障碍是缺血性脑卒中后常见并发症之一,头针疗法在治疗缺血性脑卒中及其并发症方面疗效确切。本文对近年来国内外头针治疗缺血性脑卒中后吞咽障碍的机制研究进行总结,归纳发现头针作用机制如下:(1)上调血管内皮生长因子、缺氧诱导因子-1α表达水平,激活Wnt/β-连环蛋白信号通路促进血管再生,加快脑血流速度,改善循环灌注和代谢,从而改善病灶缺血状态;(2)提高吞咽皮质兴奋性刺激麻痹的吞咽肌,平衡左右侧脑区活性增强脑网络连接,从而增强吞咽中枢功能调控;(3)上调神经生长因子、脑源性神经营养因子水平,下调肿瘤坏死因子-α、白细胞介素-6、白细胞介素-1β等促炎因子水平,改善免疫稳定性;(4)减轻兴奋性谷氨酸毒性,保护神经元;(5)提高神经突触可塑性,重塑吞咽反射通路;(6)抑制细胞凋亡,减轻神经破坏程度。头针治疗可以多途径修复神经系统损伤,促进吞咽功能恢复。今后的研究应对头针作用靶点与疗效进行进一步探索,为临床头针治疗缺血性脑卒中后吞咽障碍提供理论依据。 展开更多
关键词 头针 缺血性脑卒中 吞咽障碍 机制 细胞因子 脑网络 神经重塑 细胞凋亡
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基于类脑脉冲神经网络的边缘联邦持续学习方法
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作者 王冬芝 刘琰 +1 位作者 郭斌 於志文 《计算机科学》 北大核心 2025年第3期326-337,共12页
移动边缘计算因具有通信成本低、服务响应快等优势,已经成为适应智能物联网应用需求的重要计算模式。在实际应用场景中,一方面,单一设备能够获取到的数据通常有限;另一方面,边缘计算环境通常是动态多变的。针对以上问题,主要对边缘联邦... 移动边缘计算因具有通信成本低、服务响应快等优势,已经成为适应智能物联网应用需求的重要计算模式。在实际应用场景中,一方面,单一设备能够获取到的数据通常有限;另一方面,边缘计算环境通常是动态多变的。针对以上问题,主要对边缘联邦持续学习展开研究,将脉冲神经网络(SNN)创新性地引入到边缘联邦持续学习框架中,在降低设备计算和通信资源消耗的同时,解决本地设备在动态边缘环境中所面临的灾难性遗忘问题。利用SNN解决边缘联邦持续学习问题主要面临两个方面的挑战:首先,传统脉冲神经网络没有考虑持续增加的输入数据,难以在较长的时间跨度内存储和更新知识,导致无法实现有效的持续学习;其次,不同设备学习到的SNN模型存在差异,通过传统联邦聚合获得的全局模型无法在每个边缘设备上取得较好的性能。因此,提出了一种新的脉冲神经网络增强的边缘联邦持续学习(SNN-Enhanced Edge-FCL)方法。针对挑战一,提出了面向边缘设备的类脑持续学习算法,在单个设备上采用类脑脉冲神经网络进行本地训练,同时采用基于羊群效应的样本选择策略保存历史任务的代表样本;针对挑战二,提出了多设备协同的全局自适应聚合算法,基于SNN工作原理设计脉冲数据质量指标,并利用数据驱动的动态加权聚合方法,在全局模型聚合时对不同设备模型赋予相应权重以提升全局模型的泛化性。实验结果表明,相比基于传统神经网络的边缘联邦持续学习方法,SNN-Enhanced Edge-FCL方法在边缘设备上消耗的通信资源和计算资源减少了92%,且边缘设备在测试集上5个连续任务中的准确率都在87%以上。 展开更多
关键词 移动边缘计算 资源受限 灾难性遗忘 联邦学习 持续学习 类脑脉冲神经网络
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面向BraTS数据集的脑肿瘤分割深度学习方法研究进展 被引量:2
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作者 李学辉 魏国辉 +2 位作者 贠恺 赵文华 马志庆 《北京生物医学工程》 2025年第1期96-103,共8页
脑肿瘤分割任务在医学图像分割领域备受关注,其复杂性和多样性迫切需要研究学者采用高效的深度学习技术进行精确处理。随着深度学习技术的快速发展,各种针对脑肿瘤数据集(如BraTS)的深度学习模型层出不穷。本文综述了3种面向BraTS数据... 脑肿瘤分割任务在医学图像分割领域备受关注,其复杂性和多样性迫切需要研究学者采用高效的深度学习技术进行精确处理。随着深度学习技术的快速发展,各种针对脑肿瘤数据集(如BraTS)的深度学习模型层出不穷。本文综述了3种面向BraTS数据集的脑肿瘤分割深度学习方法的研究进展。首先,本文详细介绍了BraTS数据集的背景和来源,深入剖析该多模态数据集的结构组成和各项性能评价指标,为后续深度模型分析提供理论基础;其次,针对3种不同的深度学习模型在BraTS数据集上的性能表现进行详细探讨,包括卷积神经网络(convolutional neural network,CNN)、U型卷积网络(U-Net convolutional networks,U-Net)和Transformer等网络模型在脑肿瘤分割领域中对其基础模型做出的优化和改进,并对此类模型在面临数据集类不平衡问题和模型的建模、特征提取和特征融合等方面的挑战时所采取的策略进行深入分析;最后,本文总结了目前模型的研究趋势,并对Transformer模型的未来方向进行展望,强调在模型性能提升的同时,自监督学习和轻量化的研究将会是未来研究的焦点。本文旨为初步涉足该领域的研究学者了解当前研究现状提供深入的理解和启发,为开发更高性能、更具泛化能力的脑肿瘤分割方法提供参考。 展开更多
关键词 脑肿瘤分割 深度学习 CNN U-Net TRANSFORMER
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大规模脉冲神经网络动态加载仿真方法
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作者 沈嘉玮 才大业 +2 位作者 杨国青 吕攀 李红 《系统仿真学报》 北大核心 2025年第2期541-550,共10页
针对大规模脉冲神经网络仿真时存在GPU内存需求高的问题,提出一种针对大规模脉冲神经网络的动态加载仿真方法。通过子网络粒度的数据移动,利用主机内存作为更大的内存池,减少GPU显存对于模型仿真规模的限制,实现在单GPU的计算机进行大... 针对大规模脉冲神经网络仿真时存在GPU内存需求高的问题,提出一种针对大规模脉冲神经网络的动态加载仿真方法。通过子网络粒度的数据移动,利用主机内存作为更大的内存池,减少GPU显存对于模型仿真规模的限制,实现在单GPU的计算机进行大规模脉冲神经网络仿真,并使用流水线加速技术减少数据移动对仿真速度的影响。最终实现了在单机GPU的实验环境下仿真百万级别神经元规模的仿真,解决了在脉冲神经网络仿真过程中内存不足的问题。 展开更多
关键词 类脑计算 脉冲神经网络 神经元 突触 仿真
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基于BO-SVM和ISO改进的ENN光伏功率超短期预测模型 被引量:1
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作者 王育飞 汪弦哲 +2 位作者 薛花 余光正 杨秀 《太阳能学报》 北大核心 2025年第6期280-288,共9页
针对超短期光伏功率预测时传统大脑情绪神经网络(ENN)短反射通路拟合能力不强导致预测精度不高的问题,提出一种基于贝叶斯优化-支持向量机(BO-SVM)和改进蛇优化(ISO)的大脑情绪神经网络光伏功率预测模型。首先,为提高短反射通路的非线... 针对超短期光伏功率预测时传统大脑情绪神经网络(ENN)短反射通路拟合能力不强导致预测精度不高的问题,提出一种基于贝叶斯优化-支持向量机(BO-SVM)和改进蛇优化(ISO)的大脑情绪神经网络光伏功率预测模型。首先,为提高短反射通路的非线性拟合能力,采用基于BO-SVM的历史数据三维相点分类平面选取方法,并考虑三维相点到分类平面距离,提取历史数据非线性特征;其次,改进蛇优化算法并用于ENN的权值寻优,确保短反射通路合理表达历史数据非线性特征;然后,对光伏功率时间序列进行混沌相空间重构,并建立基于BO-SVM和ISO改进的ENN光伏功率超短期预测模型;最后,运用实测数据,验证所提模型实现不同天气下光伏功率超短期预测精度的提升。 展开更多
关键词 光伏功率 预测 混沌理论 改进大脑情绪神经网络
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基于独立成分分析评估颅脑损伤患者额顶注意网络功能异常及注意障碍神经机制
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作者 张改云 金兴兴 +3 位作者 王红霞 刘旺毅 段金辉 闫瑞芳 《中国医学影像技术》 北大核心 2025年第7期1062-1067,共6页
目的基于独立成分分析(ICA)技术评估颅脑损伤(TBI)患者额顶注意网络功能连接异常及其注意障碍神经机制。方法前瞻性纳入84例TBI,根据症状、平扫MRI表现、格拉斯哥昏迷量表(GCS)评分及Mayo颅脑外伤分级标准将其分为轻度(n=33)、中度(n=27... 目的基于独立成分分析(ICA)技术评估颅脑损伤(TBI)患者额顶注意网络功能连接异常及其注意障碍神经机制。方法前瞻性纳入84例TBI,根据症状、平扫MRI表现、格拉斯哥昏迷量表(GCS)评分及Mayo颅脑外伤分级标准将其分为轻度(n=33)、中度(n=27)及重度TBI组(n=24);以ICA提取、分析背侧注意网络(DAN)及腹侧注意网络(VAN)最佳独立成分(IC);采用多元线性回归分析注意网络内组间差异显著的脑区功能连接(FC)与经典连线测试A/B(TMT-A/B)得分的相关性。结果相比对照组及轻度TBI组,中、重度TBI组DAN[尤其双侧额眼区(FEF)]空间分布明显变小、团簇趋于离散、强度明显减弱。对照组及轻、中度TBI组VAN右侧颞顶联合区(TPJ)及右侧腹部额叶皮层(VFC)存在显著FC,重度TBI组VFC连接强度更高。TBI患者右侧VFC内FC强度与TMT-A得分呈正相关(r=0.654,P<0.001),左侧FEF内FC强度与TMT-B得分呈负相关(r=-0.383,P<0.001)。结论TBI患者额顶注意网络FC异常可能为其出现注意行为障碍的神经机制。 展开更多
关键词 脑损伤 磁共振成像 神经网络 计算机 前瞻性研究
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