Background
Mirror therapy is used to improve motor function after stroke. During mirror therapy, a mirror is placed in the person's midsagittal plane, thus reflecting movements of the non-paretic side as if it were the affected side.

Objectives
To summarise the effectiveness of mirror therapy compared with no treatment, placebo or sham therapy, or other treatments for improving motor function and motor impairment after stroke. We also aimed to assess the effects of mirror therapy on activities of daily living, pain, and visuospatial neglect.

Search methods
We searched the Cochrane Stroke Group's Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, CINAHL, AMED, PsycINFO and PEDro (last searched 16 August 2017). We also handsearched relevant conference proceedings, trials and research registers, checked reference lists, and contacted trialists, researchers and experts in our field of study.

Selection criteria
We included randomised controlled trials (RCTs) and randomised cross-over trials comparing mirror therapy with any control intervention for people after stroke.

Data collection and analysis
Two review authors independently selected trials based on the inclusion criteria, documented the methodological quality, assessed risks of bias in the included studies, and extracted data. We assessed the quality of the evidence using the GRADE approach. We analysed the results as standardised mean differences (SMDs) or mean differences (MDs) for continuous variables, and as odds ratios (ORs) for dichotomous variables.

Main results
We included 62 studies with a total of 1982 participants that compared mirror therapy with other interventions. Of these, 57 were randomised controlled trials and five randomised cross-over trials. Participants had a mean age of 59 years (30 to 73 years). Mirror therapy was provided three to seven times a week, between 15 and 60 minutes for each session for two to eight weeks (on average five times a week, 30 minutes a session for four weeks).When compared with all other interventions, we found moderate-quality evidence that mirror therapy has a significant positive effect on motor function (SMD 0.47, 95% CI 0.27 to 0.67; 1173 participants; 36 studies) and motor impairment (SMD 0.49, 95% CI 0.32 to 0.66; 1292 participants; 39 studies). However, effects on motor function are influenced by the type of control intervention. Additionally, based on moderate-quality evidence, mirror therapy may improve activities of daily living (SMD 0.48, 95% CI 0.30 to 0.65; 622 participants; 19 studies). We found low-quality evidence for a significant positive effect on pain (SMD −0.89, 95% CI −1.67 to −0.11; 248 participants; 6 studies) and no clear effect for improving visuospatial neglect (SMD 1.06, 95% CI −0.10 to 2.23; 175 participants; 5 studies). No adverse effects were reported.

Authors' conclusions
The results indicate evidence for the effectiveness of mirror therapy for improving upper extremity motor function, motor impairment, activities of daily living, and pain, at least as an adjunct to conventional rehabilitation for people after stroke. Major limitations are small sample sizes and lack of reporting of methodological details, resulting in uncertain evidence quality.

Mirror therapy for improving motor function after stroke

Brain-Computer interfaces (BCIs) enhance the capability of human brain activities to interact with the environment. Recent advancements in technology and machine learning algorithms have increased interest in electroencephalographic (EEG)-based BCI applications. EEG-based intelligent BCI systems can facilitate continuous monitoring of fluctuations in human cognitive states under monotonous tasks, which is both beneficial for people in need of healthcare support and general researchers in different domain areas. In this review, we survey the recent literature on EEG signal sensing technologies and computational intelligence approaches in BCI applications, compensating for the gaps in the systematic summary of the past five years. Specifically, we first review the current status of BCI and signal sensing technologies for collecting reliable EEG signals. Then, we demonstrate state-of-the-art computational intelligence techniques, including fuzzy models and transfer learning in machine learning and deep learning algorithms, to detect, monitor, and maintain human cognitive states and task performance in prevalent applications. Finally, we present a couple of innovative BCI-inspired healthcare applications and discuss future research directions in EEG-based BCI research.

/pdf/eeg-based-brain-computer-interfaces-bcis-a-survey-of-recent-429m85k6zs.pdf

EEG-Based Brain-Computer Interfaces (BCIs): A Survey of Recent Studies on Signal Sensing Technologies and Computational Intelligence Approaches and Their Applications

It is important to evaluate closed-loop FES (functional electrical stimulation) control systems using standard time- and frequency-domain performance metrics to facilitate the discussion of results between research groups. Moreover, uniform reporting of the performance of control methods expedites the process of developing clinically useful controllers by concentrating research efforts on promising control designs. In this article, we have focused on FES applications that benefit individuals who have spinal cord injury. However, this technology is also used for rehabilitation after stroke and traumatic brain injury and can potentially be useful for managing the effects of other neuromuscular diseases and conditions.

https://hal-lirmm.ccsd.cnrs.fr/lirmm-01636985/document

Functional Electrical Stimulation

Although there is a vast clinical literature on phantom limbs, there have been no experimental studies on the effects of visual input on phantom sensations. We introduce an inexpensive new device--a 'virtual reality box'--to resurrect the phantom visually to study inter-sensory effects. A mirror is placed vertically on the table so that the mirror reflection of the patient's intact had is 'superimposed' on the felt position of the phantom. We used this procedure on ten patients and found the following results. 1. In six patients, when the normal hand was moved, so that the phantom was perceived to move in the mirror, it was also felt to move; i.e. kinesthetic sensations emerged in the phantom. In D.S. this effect occurred even though he had never experienced any movements in the phantom for ten years before we tested him. He found the return of sensations very enjoyable. 2. Repeated practice led to a permanent 'disappearance' of the phantom arm in patient D.S. and the hand became telescoped into the stump near the shoulder. 3. Using an optical trick, impossible postures--e.g. extreme hyperextension of the fingers--could be induced visually in the phantom. In one case this was felt as a transient 'painful tug' in the phantom. 4. Five patients experienced involuntary painful 'clenching spasms' in the phantom hand and in four of them the spasms were relieved when the mirror was used to facilitate 'opening' of the phantom hand; opening was not possible without the mirror. 5. In three patients, touching the normal hand evoked precisely localized touch sensations in the phantom. Interestingly, the referral was especially pronounced when the patients actually 'saw' their phantom being touched in the mirror. Indeed, in a fourth patient (R.L.) the referral occurred only if he saw his phantom being touched: a curious form of synaesthesia. These experiments lend themselves readily to imaging studies using PET and fMRI. Taken collectively, they suggest that there is a considerable amount of latent plasticity even in the adult human brain. For example, precisely organized new pathways, bridging the two cerebral hemispheres, can emerge in less than three weeks. Furthermore, there must be a great deal of back and forth interaction between vision and touch, so that the strictly modular, hierarchical model of the brain that is currently in vogue needs to be replaced with a more dynamic, interactive model, in which 're-entrant' signalling plays the main role.

Synaesthesia in phantom Limbs induced with mirrors

Mirror Therapy for Improving Motor Function After Stroke

The purpose of this study was to evaluate the effects of mirror therapy program in addition with physical therapy methods on upper limb recovery in patients with subacute ischemic stroke. 15 subjects followed a comprehensive rehabilitative treatment, 8 subjects received only control therapy (CT) and 7 subjects received mirror therapy (MT) for 30 min every day, five times a week, for 6 weeks in addition to the conventional therapy. Brunnstrom stages, Fugl–Meyer Assessment (upper extremity), the Ashworth Scale, and Bhakta Test (finger flexion scale) were used to assess changes in upper limb motor recovery and motor function after intervention. After 6 weeks of treatment, patients in both groups showed significant improvements in the variables measured. Patients who received MT showed greater improvements compared to the CT group. The MT treatment results included: improvement of motor functions, manual skills and activities of daily living. The best results were obtained when the treatment was started soon after the stroke. MT is an easy and low-cost method to improve motor recovery of the upper limb.

Mirror therapy enhances upper extremity motor recovery in stroke patients

Motor imagery (MI) based brain-computer interfaces (BCI) extract commands in real-time and can be used to control a cursor, a robot or functional electrical stimulation (FES) devices. The control of FES devices is especially interesting for stroke rehabilitation, when a patient can use motor imagery to stimulate specific muscles in real-time. However, damage to motor areas resulting from stroke or other causes might impair control of a motor imagery BCI for rehabilitation. The current work presents a comparative evaluation of the MI-based BCI control accuracy between stroke patients and healthy subjects. Five patients who had a stroke that affected the motor system participated in the current study, and were trained across 10-24 sessions lasting about 1 h each with the recoveriX system. The participants' EEG data were classified while they imagined left or right hand movements, and real-time feedback was provided on a monitor. If the correct imagination was detected, the FES was also activated to move the left or right hand. The grand average mean accuracy was 87.4% for all patients and sessions. All patients were able to achieve at least one session with a maximum accuracy above 96%. Both the mean accuracy and the maximum accuracy were surprisingly high and above results seen with healthy controls in prior studies. Importantly, the study showed that stroke patients can control a MI BCI system with high accuracy relative to healthy persons. This may occur because these patients are highly motivated to participate in a study to improve their motor functions. Participants often reported early in the training of motor improvements and this caused additional motivation. However, it also reflects the efficacy of combining motor imagination, seeing continuous bar feedback, and real hand movement that also activates the tactile and proprioceptive systems. Results also suggested that motor function could improve even if classification accuracy did not, and suggest other new questions to explore in future work. Future studies will also be done with a first-person view 3D avatar to provide improved feedback and thereby increase each patients' sense of engagement.

/pdf/high-classification-accuracy-of-a-motor-imagery-based-brain-1hocspp7zz.pdf

High Classification Accuracy of a Motor Imagery Based Brain-Computer Interface for Stroke Rehabilitation Training

Conventional therapies do not provide paralyzed patients with closed-loop sensorimotor integration for motor rehabilitation. This work presents the recoveriX system, a hardware and software platform that combines a motor imagery (MI)-based brain-computer interface (BCI), functional electrical stimulation (FES), and visual feedback technologies for a complete sensorimotor closed-loop therapy system for poststroke rehabilitation. The proposed system was tested on two chronic stroke patients in a clinical environment. The patients were instructed to imagine the movement of either the left or right hand in random order. During these two MI tasks, two types of feedback were provided: a bar extending to the left or right side of a monitor as visual feedback and passive hand opening stimulated from FES as proprioceptive feedback. Both types of feedback relied on the BCI classification result achieved using common spatial patterns and a linear discriminant analysis classifier. After 10 sessions of recoveriX training, one patient partially regained control of wrist extension in her paretic wrist and the other patient increased the range of middle finger movement by 1 cm. A controlled group study is planned with a new version of the recoveriX system, which will have several improvements.

Brain‐Computer Interfaces With Multi‐Sensory Feedback for Stroke Rehabilitation: A Case Study

Objective Heart rate variability analysis of electrocardiogram is becoming an increasingly common method to non-invasively evaluate autonomic nervous function. The aim of the study was to investigate cardiac autonomic function in subjects with and without migraine by using 24-hour ambulatory electrocardiographic recordings. Patients and methods We investigated 27 subjects with migraine (10 with migraine with aura and 17 without aura) during headache free periods and 10 age-matched healthy control subjects. The migraine was diagnosed using the International Classification of Headache Disorders 2nd Edition criteria. Beck Depression and Beck Anxiety Inventory forms were completed by all subjects. Time and frequency-domain of HRV was analyzed for two periods: diurnal and nocturnal. Results We found an increased frequency of anxiety and depressive symptoms in migraine patients, especially in migraine with aura group. The heart rate variability parameters SDNN, RMSSD, high frequency were decreased and low frequency was increased in migraine patients during night period compared with normal subjects, most affected were migraine with aura patients. During day period we found modification for SDNN, RMSSD and high frequency parameters only in migraine with aura group. Conclusions Reduced parasympathetic activity with sympathetic predominance was found in migraine patients during the night period, most affected being migraine with aura patients.

Autonomic impairment in patients with migraine

The cardiovascular system is regulated by the autonomic nervous system, under cortical modulation. Stroke can induce cardiac autonomic imbalance, therefore, causing secondary cardiovascular complications. Heart rate variability (HRV) analysis is a simple method to appraise the autonomic nervous function. The purpose of this study was to investigate the cardiac autonomic activity in patients that suffered an ischemic stroke in middle cerebral artery (MCA) territory. Using Biopac Acquisition System, we monitored ECG in rest condition and during Ewing's tests. From these measurements, HRV parameters (using time and frequency domain analysis) were determined in 20 right MCA and 20 left MCA ischemic stroke patients, in the first 6 months after the acute event. Data were compared with 20 age- and sex-matched healthy controls. All the patients were right handed. In ischemic stroke patients, HRV parameters were significantly modified compared to controls (p < 0.05) and we found asymmetric responses to different stimulation autonomic tests between right and left hemisphere. Parameters illustrating the parasympathetic predominance in time domain (RMSSD) and frequency domain (HF) analysis were higher in left hemisphere stroke compared to right hemisphere stroke patients (p < 0.01) in resting state. From Ewing's battery test, patients with left hemisphere ischemic stroke showed predominance of parasympathetic activity to deep breathing (p < 0.01), while HRV parameters in right hemisphere ischemic stroke patients described a reduced cardiac parasympathetic innervation (p < 0.01). Cardiac autonomic imbalance occurs more often after right hemisphere ischemic stroke. HRV study may highlight cardiac dysfunctions that increase the risk of cardiovascular complications and portends a poor long-term outcome.

Bogdan Ignat

Papers

Mirror therapy enhances upper extremity motor recovery in stroke patients

High Classification Accuracy of a Motor Imagery Based Brain-Computer Interface for Stroke Rehabilitation Training

Brain‐Computer Interfaces With Multi‐Sensory Feedback for Stroke Rehabilitation: A Case Study

Autonomic impairment in patients with migraine

Cortical modulation of cardiac autonomic activity in ischemic stroke patients