Visual feedback therapy for restoration of upper limb function of stroke patients

Objective:To investigate the effects of mirror neuron theory-based visual feedback therapy(VFT)on restoration of upper limb function of stroke patients and motor-related cortical function using functional magnetic resonance imaging(fMRI).Methods:Hemiplegic stroke patients were randomly divided into two groups:a VFT group and a control(CTL)group.Sixteen patients in the VFT group received conventional rehabilitation(CR)and VFT for 8 weeks,while 15 patients in the CTL group received only CR.The Barthel Index(BI)was used to assess the activities of daily living at baseline and the 8th week of the recovery training period.The Fugl-Meyer assessment(FMA)scale,somatosensory evoked potential(SEP),and fMRI were used to evaluate the recovery effect of the training therapies.The latencies and amplitudes of N9 and N20 were measured.Before recovery training,fMRI was performed for all patients in the VFT and CTL groups.In addition,17 patients(9 in the VFT group and 8 in the CTL group)underwent fMRI for follow-up 2 months after treatment.Qualitative data were analyzed using the x2 test.The independent sample t-test was used to compare normally distributed data among different groups,the paired sample t-test was used to compare data between groups,and the non-parametric test was used to comparing data without normal distribution among groups.Results:There were no significant differences between the VFT and CTL group in all indexes.However,after 8 weeks of recovery training,these indexes were all significantly improved(P<0.05).As compared with the CTL group,the FMA scores,BI,and N9/N20 latencies and amplitudes of SEP in the VFT group were significantly improved(P<0.05).Two months after recovery training,fMRI showed that the degree of activation of the bilateral central anterior gyrus.parietal lobe,and auxiliary motor areas was significantly higher in the VFT group than the CTL group(P<0.05).Conclusions:VFT based on mirror neuron theory is an effective approach to improve upper extremity motor function and daily activity performance of stroke patients.The therapeutic mechanism promotes motor relearning by activating the mirror neuron system and motor cortex.SEP amplitudes increased only for patients who participated in visual feedback.VFT promotes sensory-motor plasticity and behavioral changes in both the motor and sensory domains.

Method for Latency Measurement of Visual Feedback-Based Master–Slave Minimally Invasive Surgical Robot

To measure the latency between human motion stimulation and stereo image display response in a visual feedback-based minimally invasive surgical(MIS) robotic system,a method was proposed by comparing the orientations of input and output events through image-processing technology. This method used a black bar to keep pace with the measured joint rotating at a number of speeds. During tests,an external camera was placed in front of the apparatus with a proper visual field,so that it can simultaneously view orientations of both bars fixed on the corresponding joints. After quantitatively analyzing the accuracy of the proposed measurement method,the method was applied to a visual feedback-based master–slave robotic system with two-degrees-of-freedom. Experimental results show that the latency of the overall system was approximately 250 ms,and the opposite clearance of the measured joint was in the range of 1.7°–1.9°.

Effects of combined rTMS and visual feedback on the rehabilitation of supernumerary phantom limbs in a patient with spinal cord injury:A case report

BACKGROUND Supernumerary phantom limb(SPL)caused by spinal cord injury(SCI)has previously been reported in several studies.However,the mechanisms and management of SPL in SCI patients are still not fully understood.Herein,we report a rare case of SPL in a patient with incomplete SCI.CASE SUMMARY A 46-year-old man complained of four hands 7 d after SCI.He was diagnosed with SPL complicated with actual limb neuropathic pain.Following a period of treatment with neurotrophic agents and Chinese traditional and analgesic medications,SPL symptoms and actual limb pain did not improve.However,his symptoms gradually lessened after combined treatment with high-frequency repetitive transcranial magnetic stimulation(rTMS),a promising neuromodulation technique,over the M1 cortex and visual feedback.After 7 wk of this treatment,SPL disappeared completely and actual limb pain was significantly relieved.CONCLUSION Cerebral plasticity changes may be a mechanism underlying the occurrence of non-painful SPL in SCI patients,and high-frequency rTMS applied to the M1 cortex could be a promising treatment method for SPL.

VFM： Visual Feedback Model for Robust Object Recognition

Object recognition, which consists of classification and detection, has two important attributes for robustness： 1） closeness： detection windows should be as close to object locations as possible, and 2） adaptiveness： object matching should be adaptive to object variations within an object class. It is difficult to satisfy both attributes using traditional methods which consider classification and detection separately; thus recent studies propose to combine them based on confidence contextualization and foreground modeling. However, these combinations neglect feature saliency and object structure, and biological evidence suggests that the feature saliency and object structure can be important in guiding the recognition from low level to high level. In fact, object recognition originates in the mechanism of ＂what＂ and ＂where＂ pathways in human visual systems. More importantly, these pathways have feedback to each other and exchange useful information, which may improve closeness and adaptiveness. Inspired by the visual feedback, we propose a robust object recognition framework by designing a computational visual feedback model （VFM） between classification and detection. In the ＂what＂ feedback, the feature saliency from classification is exploited to rectify detection windows for better closeness; while in the ＂where＂ feedback, object parts from detection are used to match object structure for better adaptiveness. Experimental results show that the ＂what＂ and ＂where＂ feedback is effective to improve closeness and adaptiveness for object recognition, and encouraging improvements are obtained on the challenging PASCAL VOC 2007 dataset.

Dynamic feedback robust stabilization of nonholonomic mobile robots based on visual servoing

This paper investigates the visual servoing robust stabilization of nonholonomic mobile robots. The calibration of visual parameters is not only complicated, but also needs great consumption of calculated time so that the accurate calibration is impossible in some situations for high requirement of real timing. Hence, it is interesting and important to consider the design of stabilizing controllers for nonholonomic kinematic systems with uncalibrated visual parameters. A novel uncertain model of these nonholonomic kinematic systems is proposed. Based on this model, a stabilizing controller is discussed by using dynamic feedback and two-step techniques. The proposed robust controller makes the mobile robot image pose and the orientation converge to the desired configuration despite the lack of depth information and the lack of precise visual parameters. The stability of the closed loop system is rigorously proved. The simulation is given to show the effectiveness of the presented controllers.

Improvement of Praxis Skills in Children with Hemiplegic Cerebral Palsy by Using New Trend of Augmented Visual and Auditory Feedback Training: A Case Report

Aims: The aim of the study is to investigate if the new method of auditory and visual biofeedback as Upper Limb Exercise may improve praxis skills alone without any traditional physical therapy treatment or not and within three successive months of treatment in children with hemiplegic cerebral palsy. Methods: A 6-year-old hemiplegic cerebral palsied child was treated with Upper-Limb Exerciser as one of augmented visual and auditory feedback devices. Sensory Integration and Praxis test was used to measure a child’s ability to integrate sensory input for perception, motor planning, and spatial actions in;Space Visualization, Figure-Ground Perception, Standing and Walking Balance, Design Copying, Postural Praxis, Bilateral Motor Coordination, Constructional Praxis, Postrotary Nystagmus, Motor Accuracy, Sequencing Praxis, Oral Praxis, Manual Form Perception, Kinesthesia, Finger Identification, Graphethesia, Localization of Tactile Stimuli, and Praxis on Verbal Command. Results: The results revealed improvement of the major standard score for each of the 17 subtests of Sensory Integration and Praxis Test when compared after three successive treatment. Conclusion: The using upper limb exerciser as one method of augmented visual and auditory feedback can be used as one of the physical and occupational therapy programs aiming to improve praxis skills in hemiplegic cerebral palsied children.

经颅磁刺激结合镜像视觉反馈训练对脑卒中后偏侧忽略的改善效果

目的 探究经颅磁刺激联合镜像视觉反馈训练系统治疗脑卒中后偏侧忽略的临床疗效。方法 选取2021年1月-2022年12月就诊于上海市同仁医院康复科的脑卒中偏侧忽略患者60例作为研究对象,根据随机数字表法分为对照组和联合组,各30例。对照组接受经颅磁刺激治疗,联合组接受经颅磁刺激联合镜像视觉反馈训练。治疗前及治疗4周后,比较两组蒙特利尔认知评估(MoCA)量表评分、中国行为性忽略测试-香港版(CBIT-HK)量表评分、凯瑟琳-波哥量表(CBS)评分及改良Barthel指数(MBI)评分。结果 治疗后,联合组MoCA评分、CBIT-HK评分、MBI评分均高于对照组(P<0.05),CBS评分低于对照组(P<0.05)。结论 经颅磁刺激联合镜像视觉反馈训练能更好地改善脑卒中后偏侧忽略。

可视化反馈促进自我调节学习的实验研究

建设终身学习型社会要求学习者具备更高的自我调节学习能力。这就要求教育不仅要教会学生知识,更要教会学生学习。然而,当前关于促进基础教育中学习者自我调节学习的研究较少,并且缺乏可以应用于线下课堂的实用工具,导致测评数据无法被深入解读。立足于基础教育课堂教学,设计开发促进学习者自我调节学习的可视化反馈工具,深入分析测评数据,挖掘其中蕴藏的有效信息。该工具提供包括自我认识、学习动机、学习策略三个维度的可视化反馈报告,将知识掌握情况、错题归因、试题定位等信息呈现给学习者,助力其自我调节学习的发生。为检验该工具的效果,在两个班级开展对比实验,对两组学生的自我调节学习能力和学习成绩进行差异性检验。独立样本T检验结果显示,实验班和对照班在自我调节学习能力和学习成绩之间均存在显著性差异,并且均呈现出0.4左右的效应量。证明该工具提供的可视化反馈报告能够有效促进学习者的自我调节学习,同时能够促进学业表现。

基于PSO-BP神经网络的分拣机器人视觉反馈跟踪

针对分拣机器人视觉反馈跟踪精度差、耗时较长的问题,研究基于粒子群算法-反向传播(particle swarm optimization-back propagation,PSO-BP)神经网络的分拣机器人视觉反馈跟踪方法,以提升视觉反馈跟踪效果。依据分拣机器人的视觉反馈信息,建立分拣机器人运动学模型,并求解分拣机器人机械臂输出位置和输入位置的误差函数;利用PSO算法优化BP神经网络的权值与偏置;在权值与偏置优化后的BP神经网络内,输入误差函数,预测分拣机器人视觉反馈跟踪控制量;利用预测视觉反馈跟踪控制量,在线调整增量式比例-积分-微分(proportional-integral-derivative,PID)的参数,输出高精度的分拣机器人视觉反馈跟踪控制量,实现分拣机器人视觉反馈跟踪。实验结果表明,该方法可有效视觉反馈跟踪分拣机器人机械臂的关节角;存在干扰情况下,在运行时间为10 s左右时,阶跃响应趋于稳定;有干扰情况下,视觉反馈跟踪的平均误差为0.09 cm,耗时平均值为0.10 ms;无干扰情况下,平均误差为0.03 cm,耗时平均值为0.04 ms。

运动人因视角下体育馆光环境评价预测模型研究

体育馆光环境设计直接影响运动者的舒适水平。为探究运动者对天然光环境的舒适需求反馈,本文基于主观调查与客观生理测量的互证方法,确定运动者光环境评价影响因素,利用神经网络算法构建以运动人因健康为导向的体育馆光环境评价预测模型,并结合遗传算法优化迭代得出适宜全民健身的体育馆天然光环境视觉舒适亮度阈值。

基于视觉反馈的柔性充气仿生臂控制系统设计

设计了一种基于视觉反馈的柔性仿生臂控制系统,通过将其等效为刚体的建模方法对所设计的柔性仿生臂进行了理论分析。利用手动操纵杆实现了对柔性仿生臂的手动操控。在柔性仿生臂头端安装有摄像头,可以通过卷积神经网络目标检测和识别算法识别目标物体,其获得的位置信息可用于闭环控制。通过视觉反馈实现了对目标的搜索和锁定。相较于传统的刚性机械臂,本研究具有安全性高和体积小的优点。同时,计算机仿真和实验均验证了该设计的合理性与有效性。

视觉反馈平衡训练对脑卒中后平衡与步态康复的研究进展

脑卒中后患者肢体功能障碍及并发症较多,预后不良,严重影响其生活质量。研究显示,视觉反馈平衡训练可通过视觉反馈、镜像神经元激活、中枢刺激易化神经通路等机制改善脑卒中患者的平衡与步态,在提高患者康复主动性及生存质量方面有积极意义。本文综述了视觉反馈平衡训练的作用原理,概括了该技术对脑卒中患者平衡与步态康复的作用机制,分析其研究现状及进展,以期为视觉反馈平衡训练方法的优化及脑卒中平衡与步态的康复提供新思路。

视觉反馈训练对脊髓损伤患者运动功能康复作用机制的功能MRI研究进展

视觉反馈训练(visual feedback training, VFT)已经被广泛应用于脊髓损伤(spinal cord injury, SCI)及其他各种运动功能障碍性疾病的康复治疗,并取得较好疗效,但其对运动功能影响的神经机制尚不清楚。随着功能MRI的发展,研究发现VFT与大脑网络间和网络内的功能连接改变及感觉运动皮层的激活有一定相关性,为揭示其促进运动功能康复的神经机制提供了理论依据。因此,本文就VFT对SCI患者运动功能康复作用机制的功能MRI研究进展进行综述,旨在为VFT在SCI患者运动康复中的临床应用提供神经影像学证据。

县域中小学职初教师培养问题分析与优化建议

统筹规划好全县职初教师的培养是县级师训部门的重要职责。当前县域职初教师培养存在一些突出的问题,诸如课程体系不完善、优质培训资源匮乏、组织管理混乱、参训内生动力不足、培训效果无法预期等。解决这些问题,需要从根本上厘清教师培训的性质与价值导向等问题。建议师训部门从培训内容设置、目标定位、组织实施和效果评估等四个方面进行顶层设计,并对每个环节进行精细化运作,构建以“全景、进阶、协同、可视”为主要特征的县域职初教师培养的机制体制。

运动想象疗法联合视觉反馈训练在脑卒中偏瘫患者早期康复中的应用效果

目的:观察运动想象疗法联合视觉反馈训练在脑卒中偏瘫患者早期康复中的应用效果。方法:选取2021年3月—2022年6月于渭南市蒲城县医院接受康复训练的脑卒中偏瘫患者76例作为研究对象,采用随机数字表法分为常规训练组与联合训练组,各38例。常规训练组接受常规训练,联合训练组在常规训练组基础上接受运动想象疗法联合视觉反馈训练。比较两组生活能力、肢体功能、平衡能力。结果:干预后,两组自主如厕、自主穿衣、自主洗澡、自主运动、自主进食评分升高,联合训练组高于常规训练组,差异有统计学意义(P<0.05);干预后,两组运动能力、协调能力、感觉能力、关节活动能力评分升高,联合训练组高于常规训练组,差异有统计学意义(P<0.05);干预后,两组站立平衡、坐卧平衡、上臂前伸平衡、闭眼站立平衡、转身平衡评分升高,联合训练组高于常规训练组,差异有统计学意义(P<0.05)。结论:运动想象疗法联合视觉反馈训练在脑卒中偏瘫患者早期康复中的应用效果显著,可提高患者生活能力、肢体功能、平衡能力。

基于双重反馈的水炮射流稳定系统

在海上执法的过程中,执法船只经常会遭遇风浪,而风浪带来的船体晃动会导致水炮晃动,使水炮射流无法准确命中目标。现有的水炮系统多采用单反馈控制方法,没有考虑到载体运动对水射流的干扰。为了减轻载体运动对水炮射流的干扰,本文提出了一种基于双重反馈的水炮射流稳定系统。该系统利用IMU采集载体运动姿态,利用自回归滑动平均模型对载体姿态进行补偿;利用摄像机采集射流落点信息,通过反向传播算法实时调整射流模型参数,并对水炮关节角度进行反馈调整。在智能水炮平台上的实验结果表明,采用双重反馈机制后,水炮的射击误差可有效降低33%以上。

Control System Design and Validation for Visual Based Indoor Inspection Helicopter

This paper is on control system design for visual based indoor inspection by the model helicopters. For the indoor inspection system for large structures, there are some cases where it is difficult for htunans to work with. This paper introduces indoor inspection helicopter system with only inspection camera and prism for position sensing as payload. The control system is designed to help the operator of the inspection system to control the helicopter to designated position without much practice. The cases of the control by experienced and novice operators are compared and results show that the system has feasibility for indoor inspection system to be used by any kind of users.

二阶锥约束规划的机器人视觉闭环位姿自协调方法

将机器人“手-眼”位姿自协调视为无标定约束规划问题,提出一种基于二阶锥约束规划的视觉闭环控制方法。在图像平面和笛卡儿空间分别建立基于图像与基于位姿的视觉伺服控制算法;在路径约束和局部极小约束准则下构建二阶锥凸优化模型,实现了图像特征轨迹和机器人运动路径折中最优;将所提出的二阶锥约束规划模型嵌入自适应状态估计器,实现了机器人雅可比矩阵在线映射学习,解决了“手-眼”标定参数和视觉深度信息未知问题;最后通过无标定机器人视觉定位证明了二阶锥约束规划模型的有效性,真实环境抓取操作表明了机器人位姿自协调控制的可行性。

缺乏位置信息的视觉移动机器人leader-following编队控制

针对视觉移动机器人编队在缺乏位置信息情况下的控制问题,提出一种基于视觉的leader-following编队反馈控制方法。该方法利用leader标志物特征点在follower摄像机像平面上的坐标信息设计了观测器,对leader与follower间的相对位置进行估计,基于相对位置估计量与它们速度的关系,设计出leader-following编队反馈控制器,通过Lyapunov理论证明了闭环系统的稳定性。仿真结果表明,该控制方法能有效解决缺乏位置信息情况下视觉移动机器人编队的控制问题。

基于视觉反馈的姿势控制训练改善帕金森病患者平衡功能及日常生活活动能力的临床观察

目的:探讨基于视觉反馈的姿势控制训练对帕金森病患者的平衡功能及日常生活活动能力的影响。方法:纳入2018年1月至2021年12月于我院就诊的帕金森病患者60例,按照随机数字表法随机分为试验组和对照组,每组各30例。对照组接受常规的康复训练,试验组在对照组的基础上给予基于视觉反馈的动态平衡训练及核心肌群控制训练,共治疗8周。两组在治疗前、治疗8周后均进行Berg平衡量表(BBS)、起立-行走计时测试(timed“up and go”test,TUGT)及改良的Barthel指数(MBI)评定,并对两组患者的临床疗效及康复训练满意度进行分析比较。结果:治疗后,两组患者BBS[(49.00±1.97)vs.(44.77±1.78)]、TUGT[(10.17±2.31)vs.(13.67±2.26)]、MBI[(64.83±6.09)vs.(54.33±7.51)]评分均优于治疗前,具有显著性差异(P<0.05);与对照组比较,试验组BBS(49.00±1.97)、TUGT(10.17±2.31)、MBI(64.83±6.09)均优于对照组,差异有显著性(P<0.05);试验组患者康复训练效果满意度为93.33%,与对照组(70.00%)比较有显著性优势,差异有显著性(P<0.05)。结论:常规康复训练能够改善帕金森病患者的平衡功能及日常生活活动能力,在此基础上,增加视觉反馈的姿势控制训练效果更显著,具有一定的临床推广价值。