Improving motor imagery practice with synchronous action observation in stroke patients

Background: Action observation (AO) has the potential to improve motor imagery (MI) practice in stroke patients. However, currently only a few results are available on how to use AO effectively.

Objective: The aim of this study is to investigate whether MI practice can be improved more effectively by synchronous AO than by asynchronous AO.

Methods: Ten patients with upper limb motor dysfunction following stroke were selected as the participants. They were divided into two groups to perform MI practice combined with a daily conventional rehabilitation for four consecutive weeks. The control group was asked to perform MI guided by asynchronous AO (MIAAO), and the experimental group was asked to perform the same MI but guided by synchronous AO (MISAO). The event-related power decrease (ERD) in sensorimotor rhythms of electroencephalograph was calculated to reflect the sensorimotor cortex activation and to assess the cortex excitability during MI. Fugl-Meyer assessment (FMA) and pinch strength test (PST) were used to assess the limb motor recovery.

Results: The ERD pattern of the experimental group not only had greater amplitude and longer duration, but also included more frequency components. Furthermore, the effect sizes of ERD values between the two groups continuously increased (d_ES > 0.8) during the course of treatment. Moreover, the FMA and PST scores achieved with MISAO were also significantly higher than those achieved with MIAAO (p < 0.05).

Conclusions: Compared with MIAAO, MISAO can enhance the excitation of sensorimotor cortex more effectively and lead to a more rapid neurorehabilitation of stroke patients.     

Leap motion controlled videogame-based therapy for rehabilitation of elderly patients with subacute stroke: a feasibility pilot study

Abstract

Background:

The leap motion controller (LMC) is a new optoelectronic system for capturing motion of both hands and controlling a virtual environment. Differently from previous devices, it optoelectronically tracks the fine movements of fingers neither using glows nor markers.

Objective:

This pilot study explored the feasibility of adapting the LMC, developed for videogames, to neurorehabilitation of elderly with subacute stroke.

Methods:

Four elderly patients (71.50?±?4.51 years old) affected by stroke in subacute phase were enrolled and tested in a cross-over pilot trial in which six sessions of 30 minutes of LMC videogame-based therapy were added on conventional therapy. Measurements involved participation to the sessions, evaluated by means of the Pittsburgh Rehabilitation Participation Scale, hand ability and grasp force evaluated respectively by means of the Abilhand Scale and by means of the dynamometer.

Results:

Neither adverse effects nor spasticity increments were observed during LMC training. Participation to the sessions was excellent in three patients and very good in one patient during the LMC trial. In this period, patients showed a significantly higher improvement in hand abilities (P?=?0.028) and grasp force (P?=?0.006).

Conclusions:

This feasibility pilot study was the first one using leap motion controller for conducting a videogame-based therapy. This study provided a proof of concept that LMC can be a suitable tool even for elderly patients with subacute stroke. LMC training was in fact performed with a high level of active participation, without adverse effects, and contributed to increase the recovery of hand abilities.     

Behavioral and neurophysiological mechanisms underlying motor skill learning in patients with post-stroke hemiparesis

Objective

Given the presence of execution deficits after stroke, it is difficult to determine if patients with stroke have deficits in motor skill learning with the paretic arm. Here, we controlled for execution deficits while testing practice effects of the paretic arm on motor skill learning, long-term retention, and corticospinal excitability.

An fMRI study of action observation and action execution in childhood

Although many studies have examined the location and function of the mirror neuron system (MNS) in human adults, we know relatively little about its development. The current study fills this gap by using fMRI to examine for the first time the development of the brain regions implicated in action execution, action observation, and their overlap. We examined age-related differences in brain activation by contrasting a group of children (n = 21) and adults (n = 18). Surfaced-based analyses of action execution and action observation revealed that brain activity for action observation and execution in children is similar to adults, though adults displayed greater activity than children within the right superior parietal lobe during action execution and the occipital lobe during action observation compared to control. Further, within-individual measures of overlapping activation between action observation and execution revealed age-related differences, such that adults, compared to children, displayed more spatial overlap. Moreover, the extent of the overlap in activation across conditions was related to better motor skills and action representation abilities in children. These data indicate that the MNS changes between middle childhood and adulthood. The data also demonstrate the functional significance of the putative MNS to motor skills and action representation during development.     

人-环境-作业模式促进脑卒中后手和上肢功能的康复

一侧肢体功能障碍是脑卒中后的典型症状,其中手和上肢功能障碍严重影响着作业表现,使患者的生活受到不同程度的限制。本文基于人-环境-作业(personenvironment-occupation,PEO)模式,从人、环境、作业活动和作业表现等方面,探讨脑卒中患者手和上肢功能的康复治疗,以期提升人们对中国脑卒中患者作业治疗内涵的理解。通过作业治疗,可以改善患者的行为表现,减轻功能受限程度,增强日常生活的活动能力,从而提高患者的生活质量。     

Sex and individual differences in induced and evoked EEG measures of action observation

We used two established methods for analysing the EEG response of the neurotypical adult human brain to examine the execution and observation of simple motor actions. In one, execution or observation of a button-press in response to a tone caused a decrease in the power at 8-13 Hz (“mu”) frequencies. In the other, the response preparation (or the inferred response preparation when these actions are observed in another person) was measured by the averaged response time-locked potentials measured over motor cortex - the “readiness potential”. Results indicated that the mirrored readiness potentials were bilaterally generated. We found sex differences for both measures. However, whereas females showed a greater degree of response for the mu power measure during the observation of movement only, males showed larger readiness potentials during both movement performance and observation. Both measures have been claimed to be neural correlates of mirror systems in the brain where processes responsible for actions are linked to the perception of such actions. Such mirror systems have also been implicated in higher order social cognition such as empathy. However, we found no correlations between either of our EEG measures and self-report scales of social cognition. The results imply sex differences in the measured systems and for mirroring that are not directly related to social cognition. We suggest that the results may indicate two dissociable motor mirroring systems that can be measured by induced and evoked EEG.     

Effects of right unilateral electroconvulsive therapy on motor cortical excitability in depressive patients

Electroconvulsive therapy (ECT) is a widely acknowledged effective treatment for severe major depression. ECT produces considerable anticonvulsant effects that may be related to an increased GABA-ergic neurotransmission. We aimed to explore whether motor cortical excitability as assessed with single and paired pulse transcranial magnetic stimulation (TMS) could be used to investigate these anticonvulsant effects. Therefore, parameters of motor cortical excitability were investigated in 10 patients before and after 10 sessions of right unilateral ECT. After 10 sessions of right unilateral ECT, an enhanced activity of inhibitory circuits in human motor cortex had been observed, as measured by both increased intracortical inhibition and cortical silent period duration, whereas intracortical facilitation and resting motor threshold remained unchanged. The reduction of seizure duration in the course of ECT was associated with clinical improvement and an increase in intracortical inhibition. We interpret this finding as further indirect evidence for changes in inhibitory circuits in the course of ECT in patients with major depression.     

Effects of observing normal and abnormal goal‐directed hand movements on somatosensory cortical activation

Existing evidence indicates the importance of observing correct, normal actions on the motor cortical activities. However, the exact neurophysiological mechanisms, particularly in the somatosensory system, remain unclear. This study aimed to elucidate the effects of observing normal and abnormal hand movements on the contralateral primary somatosensory (cSI), contralateral (cSII) and ipsilateral (iSII) secondary somatosensory activities. Experiment I was designed to investigate the effects of motor outputs on the somatosensory processing, in which subjects were instructed to relax or manipulate a small cube. Experiment II was tailored to examine the somatosensory responses to the observation of normal (Normal) and abnormal (Abnormal) hand movements. The subjects received electrical stimulation to right median nerve and magnetoencephalography (MEG) recordings during the whole experimental period. Regional cortical activation and functional connectivity were analyzed. Compared to the resting condition, a reduction in cSI and an enhancement of SII activation was found when subjects manipulated a cube, suggesting the motor outputs have an influence on the somatosensory responses. Further investigation of the effects of observing different hand movements showed that cSII activity was significantly stronger in the Normal than Abnormal condition. Moreover, compared with Abnormal condition, a higher cortical coherence of cSI‐iSII at theta bands and cSII‐iSII at beta bands was found in Normal condition. Conclusively, the present results suggest stronger activation and enhanced functional connectivity within the somatosensory system during the observation of normal than abnormal hand movements. These findings also highlight the importance of viewing normal, correct hands movements in the stroke rehabilitation.     

Motor network activation during human action observation and imagery: Mu rhythm EEG evidence on typical and atypical neurodevelopment

The mental simulation theory suggests activation of the motor network during imagery and observation of human movements, similarly to the activation during action execution and is proposed to be mediated by the mirror neuron system. This activation can be measured by several technologies such as electroencephalography, magnetoencephalography, functional magnetic resonance imaging and positron emission tomography. It is proposed that motor network activation and therefore increased cortical excitability of primary motor cortex occur due to premotor mirror neuron system inputs. This mechanism has been demonstrated as important for planning actions and seems relevant for anticipating others actions and for empathy establishing as well as for language development. In this review we focused on studies relative to electroencephalography data of motor neural network activation during movement observation and imagery in typical and atypical development.     

娱乐康复对卒中后抑郁及神经功能缺损改善的疗效分析

目的 观察娱乐康复对卒中后抑郁及神经功能缺损改善的影响.方法 160例卒中后抑郁患者随机分为对照组和干预组,各80例.均采用常规治疗,干预组则在此基础之上给予娱乐康复.治疗前后分别采用Zung抑郁自评量表（SDS）、汉密尔顿抑郁量表（HAMD）、神经功能缺损程度评分标准（NFDS）、日常生活能力量表（ADL）进行评定.结果 干预前两组患者各项指标组间差异均无统计学意义（P＞0.05）,治疗3月后SDS、HAMD、NFDS、ADL评分较治疗前均明显改善（P＜0.05）,且干预组上述指标改善幅度均优于对照组,组间差异有统计学意义（P＜0.05）.结论 娱乐康复对改善卒中后抑郁及神经功能缺损效果显著.     

Effects of botulinum toxin A therapy and multidisciplinary rehabilitation on lower limb spasticity classified by spastic muscle echo intensity in post-stroke patients

Objectives: The purpose of the present study was to investigate retrospectively the relationship between botulinum toxin type A plus multidisciplinary rehabilitation and muscle echo intensity in post-stroke patients with spasticity. The primary aim was to investigate whether the effects of the intervention on the improvement of spasticity depend on muscle echo intensity, and the secondary aim was to investigate whether the motor function of the lower limbs depends on muscle echo intensity.

Methods: A 12-day inpatient protocol was designed for 102 post-stroke patients with spasticity due to lower limb paralysis. Muscle echo intensity of the triceps surae muscle was measured by ultrasonography, and the patients were categorized into four groups based on Heckmatt scale grades (Grades I–IV).

Results: All four groups classified by the Heckmatt scale showed significant pre-to-post-intervention differences in the knee and ankle modified Ashworth scale scores (p < 0.05). Grades I–III patient groups showed a significant improvement in lower limb motor function following intervention. Grade IV patients did not show a significant improvement in lower limb motor function.

Conclusions: We observed significant improvements in the modified Ashworth scale scores after botulinum toxin type A and multidisciplinary rehabilitation therapy on post-stroke patients with spasticity. Although patients with lower muscle echo intensity demonstrated improvements in motor function, the improvement was poor in those with higher muscle echo intensity.     

Lateralized EEG mu power during action observation and motor imagery in typically developing children and children with unilateral Cerebral Palsy

ObjectiveDuring motor execution (ME), mu power is diminished over the contralateral hemisphere and increased over the ipsilateral hemisphere, which has been associated with cortical activation of the contralateral motor areas and inhibition of the ipsilateral motor areas respectively. The influence of action observation (AO) and motor imagery (MI) on mu power is less clear, especially in children, and remains to be studied in children with unilateral cerebral palsy (uCP).MethodsWe determined mu power during ME, AO, and MI of 45 typically developing (TD) children and 15 children with uCP over both hemispheres, for each hand.ResultsIn TD children, over the left hemisphere mu power was lowered during ME when the right hand was used. In line, over the right hemisphere mu power was lowered when the left hand was addressed. In addition, during AO and MI increased mu power was observed when the right hand was addressed. In children with uCP, over the spared hemisphere mu power was diminished during ME when the less-affected hand was used. However, over the lesioned hemisphere, no mu changes were observed.ConclusionsThe results of TD children fit the activation/inhibition model of mu power.SignificanceThe results of children with uCP suggest that the lesioned hemisphere is unresponsive to the motor tasks.     

Visuomotor priming effects in Parkinson's disease patients depend on the match between the observed and the executed action

Evidence exists that action observation activates the same cortical motor areas that are involved in the performance of the observed actions. An untested idea is whether subcortical structures such as the basal ganglia play a role in the coding of other people's actions. This study used kinematics to examine how Parkinson's disease patients react to the observation of an action which they were subsequently requested to perform. In each trial a model and an observer, which could be either a Parkinsonian patient or a neurologically healthy participant, were seated facing each other. The model was requested to grasp a stimulus (action condition), to perform a kicking action towards the stimulus (control-action condition), and to not perform any action (control condition). The task for the observer was always to grasp the stimulus after having watched the model performing her task. Results show that Parkinson's disease patients did show facilitation effects only when the model was a Parkinsonian patient. Whereas, neurologically healthy participants’ movements were facilitated following the observation of either the Parkinsonian and the healthy model grasping the object. No facilitation effects were found for both the control and the control-action conditions. The fact that normal visuomotor priming takes place in PD patients when the observed action matches with what they can perform suggests that basal ganglia might not be necessary for it. However, damage to the basal ganglia might become relevant when such a match does not occur. In such circumstances, a damage to these structures might prevent the deployment of additional activity which might be necessary to influence cortical functions related to the representations of observed actions.     

呼吸肌训练经皮质-膈肌通路对缺血性脑卒中患者的作用机制分析

目的 分析呼吸肌训练经皮质-膈肌通路对缺血性脑卒中患者的作用机制。方法 选取2019年6月-2021年6月本院收治的98例缺血性脑卒中患者作为研究对象,按照随机数字表法按1∶1比例分为观察组、对照组,每组各49例;对照组采用常规康复训练,观察组在对照组基础上加用呼吸肌训练;比较2组治疗前、治疗8周后呼吸肌功能[最大吸气压(Maximum inspiratory pressure, MIP)、最大呼气压(Maximal expiratory pressure, MEP)、胸廓活动度]、躯干损伤量表(Trunk impaiment scale, TIS)、Fugl-Meyer评定量表(Fugl-Meyer assessment, FMA)、简易上肢功能检查量表(Simple test for evaluating hand function, STEF)、三维步态、Barthel指数(Barthelindex, BI)、脑卒中专门化生活质量量表(Stroke specific quality of life scale, SS-QOL)评分、皮质-膈肌通路[膈神经运动传导(Phrenic ...     

抗抑郁治疗对老年脑卒中后抑郁及康复的影响

目的:观察抗抑郁治疗对老年缺血性脑卒中后抑郁症状及神经功能康复的作用.方法:将老年脑卒中后抑郁患者356例分为文拉法辛组128例、阿米替林组116例及对照组112例,于治疗前后进行汉密尔顿抑郁量表(HAMD)和神经功能缺损量表(CSS)、日常生活能力量表(ADL)评定.结果:文拉法辛组和阿米替林组治疗第2周HAMD评分和第12周CSS评分较治疗前和对照组均明显降低;文拉法辛组和阿米替林组3个月后ADL亦明显改善(P均＜0.05),但阿米替林组不良反应明显高于文拉法辛组.结论:抗抑郁治疗有利于老年脑卒中后抑郁患者神经功能康复,提高生活能力,减少并发症.     

卒中患者T淋巴细胞亚型的变化与卒中后感染的关系

目的 观测卒中患者外周血T细胞亚型的改变,探讨卒中后感染发生的危险因素.方法取卒中患者(n=37)入院时、入院后第1、7和14天以及对照组(同期体检的健康患者20例)的外周血,流式细胞仪检测外周血CD3+、CD4+、CD8+及CD4+/CD8+变化,将符合标准的卒中患者纳入感染组和未感染组,Logistic回归分析卒中后发生感染的易感因素.结果 卒中患者CD3+、CD4+和CD8+T细胞百分比较对照组明显下降,差异均有统计学意义(P＜0.05).在卒中后出现感染的患者(n=12),在入院后的第1、7、14天外周血CD3+、CD4+和CD8+T细胞百分比逐步上升,但在整个观察期内仍明显低于对照组,差异均有统计学意义(P＜0.05);卒中后未发生感染的患者(n=12),CD4+T细胞百分比在入院后第1天起与对照组比较,差异均无统计学意义(P＞0.05).Logistic回归分析结果显示卒中入院时CD4+、CD8+T细胞百分比,入院第1天CD3+、CD4+T细胞百分比,入院第7天CD3+、CD4+、CD8+T细胞百分比以及入院第14天CD3+T细胞百分比与卒中后发生感染密切相关.结论 卒中患者存在外周血T细胞亚型的变化和免疫功能的降低,T细胞亚型的变化可能对卒中后感染的发生有一定的影响.     

Action observation improves sit-to-walk in patients with Parkinson's disease and freezing of gait. Biomechanical analysis of performance

IntroductionFreezing of gait (FoG) is one of the most disabling gait disorders in Parkinson's disease (PD), reflecting motor and cognitive impairments, mainly related to dopamine deficiency. Recent studies investigating kinematic and kinetic factors affecting gait in these patients showed a postural instability characterized by disturbed weight-shifting, inappropriate anticipatory postural adjustment, worse reactive postural control, and a difficulty executing complex motor tasks (i.e. sit-to-walk). These symptoms are difficult to alleviate and not very responsive to Levodopa. For this reason, additional therapeutic actions based on specific therapeutic protocols may help patients with their daily lives. We conducted a randomized control trial aimed to test if two clinical protocols for PD patients with FoG were effective to improve postural control.MethodsRehabilitation protocols, conceived to improve gait, were based on learning motor exercises with the Action Observation plus Sonification (AOS) technique, or by the use of external sensory cues. We collected biomechanical data (Center of Mass COM, Center of Pressure COP, and moving timings), using the sit-to-walk task as a measure of motor and gait performance.ResultsKinetic and kinematic data showed that when treatment effects consolidate, patients treated with AOS protocol are more efficient in merging subsequent motor tasks (sit-to-stand and gait initiation), and diminished the total moving time and the area of the COP positions.ConclusionWe demonstrated for the first time that PD patients with FoG treated with an AOS protocol aimed at relearning appropriate gait patterns increased balance control and re-acquired more efficient postural control.     

头皮脑电图发作间期持续周期性局限性低波幅棘波的皮质脑电图特点及其对致痫灶的定位意义

目的 通过分析头皮脑电图上周期性局限性低波幅棘波的皮质脑电图特点,揭示皮质电场被头皮脑电图记录到的影响因素及此种低波幅棘波对致痫灶的定位意义.方法 以5例头皮脑电图上发作间期表现为周期性局限性低波幅棘波持续性发放为特点的难治性癫痫患者为研究对象.应用DaVinci系统所提供的数据分析功能对头皮脑电图和皮质脑电图上所记录的发作间期的棘波进行分析,测量棘波的波幅及棘波灶的范围;应用Matlab和Spike2软件的功率谱密度、自相关图和相干性分析等功能分析棘波灶的周期性震荡活动和同步性电活动;应用t检验进行统计学分析.结果 5例患者在头皮脑电图所记录的棘波的波幅(μV)分别为:22.2±4.8、30.4±7.1、20.7±3.2、58.4±10.1、23.4±3.9;在皮质脑电图所记录的棘波的波幅(μV)分别为:1253.8±199.3、806.5±161.4、1585.7±305.7、922.5 ±140.6、736.8 ±70.9.t检验显示皮质脑电图的棘波波幅显著高于头皮脑电图所记录到的棘波波幅(t=6.394,P＜0.05).5例患者棘波灶在大脑皮质上的面积(cm2)分别为:4.0、6.0、3.5、5.5、6.5.功率谱密度和自相关图分析表明这些棘波灶存在1～3 Hz的周期性震荡活动.互相关图和相干性分析表明皮质脑电图棘波灶内各电极触点的电活动具有同步性.结论 头皮脑电图发作间期持续周期性局限性低波幅棘波,对癫痫患者的术前定位具有一定的参考价值.