EEG-Based Evidence of Mirror Neuron Activity from App-Mediated Stroke Patient Observation

Video parameters for action observation training in stroke rehabilitation: a scoping review

PURPOSE

Action observation training (AOT) is a therapeutic approach used in stroke rehabilitation. Videos form the core of AOT, and knowledge of constituent parameters is essential to make the intervention robust and generalizable. Currently, there is a dearth of available information on video parameters to be used for AOT. Our purpose was to identify and describe the parameters that constitute AOT videos for stroke rehabilitation.

METHOD

Electronic databases like PubMed, CINAHL, Scopus, Web of Science, ProQuest, and Ovid SP from inception to date according to PRISMA-ScR guidelines. Title, abstract, and full-text screening were done independently by two authors, with a third author for conflict resolution. Data on video parameters like length, quality, perspective, speed, screen size and distance, sound, and control videos were extracted.

RESULTS

Seventy studies were included in this review. The most-reported parameters were video length (85.71%) and perspective of view (62.85%). Movement speed (7.14%) and sound (8.57%) were the least reported. Static landscapes or geometrical patterns were found suitable as control videos.

CONCLUSION

Most video parameters except for length and perspective of view remain underreported in AOT protocols. Future studies with better descriptions of video parameters are required for comprehensive AOT interventions and result generalisation.

Development of digital mirror therapy for stroke-severe patients

Mirror therapy (MT), which is used in the existing stroke rehabilitation environment, has significant limitations for use with severe stroke patients. Since mirrors only reflect symmetrical movement, allowing a patient to observe precise asymmetrical movement is impossible. This study proposes a new MT system by developing a pyramid hologram technology that uses delayed motion to create realistic images. Significant differences, observed via electroencephalogram, were shown in all motor cortex channels immediately after the event in the delayed condition when compared to before the event (C3: p < 0.001; Cz: p < 0.001, C4: p < 0.001). The illusion of asymmetrical movement using the proposed system can be applied to severe stroke patients to increase the positive outcome of rehabilitation.

Effect of virtual running with exercise on functionality in pre-frail and frail elderly people: randomized clinical trial

BACKGROUND

Virtual mirror therapies could increase the results of exercise, since the mirror neuron system produces an activation of motor execution cortical areas by observing actions performed by others. In this way, pre-frail and frail people could use this system to reach an exercise capacity threshold and obtain health benefits.

AIM

The aim of this study is to evaluate the effects of a virtual running (VR) treatment combined with specific physical gait exercise (PE) compared to placebo VR treatment combined with PE on functionality, pain, and muscular tone in pre-frail and frail older persons.

METHODS

A single blinded, two-arm, randomised controlled trial design was employed. Thirty-eight participants were divided into two intervention arms: Experimental Intervention (EI) group, in which VR and gait-specific physical exercises were administered and Control Intervention (CI) group, in which a placebo virtual gait and the same exercise programme was administered. Functionality, pain, and tone were assessed.

RESULTS

EI group improved in aerobic capacity, functional lower-limb strength, reaction time, and pain, while CI group remained the same. Regarding static balance and muscle tone, no differences were found for either group. Further analysis is needed to asses VR effectiveness for improving gait, stand-up and sit-down performance and velocity.

CONCLUSIONS

Virtual running therapy appears to enhance capacities related with voluntary movements (i.e., aerobic capacity, functional lower-limb strength, and reaction time) and reduce pain.

Action Observation Therapy for Arm Recovery after Stroke: A Preliminary Investigation on a Novel Protocol with EEG Monitoring

This preliminary study introduces a novel action observation therapy (AOT) protocol associated with electroencephalographic (EEG) monitoring to be used in the future as a rehabilitation strategy for the upper limb in patients with subacute stroke. To provide initial evidence on the usefulness of this method, we compared the outcome of 11 patients who received daily AOT for three weeks with that of patients who undertook two other approaches recently investigated by our group, namely intensive conventional therapy (ICT), and robot-assisted therapy combined with functional electrical stimulation (RAT-FES). The three rehabilitative interventions showed similar arm motor recovery as indexed by Fugl-Meyer's assessment of the upper extremity (FMA_UE) and box and block test (BBT). The improvement in the FMA_UE was yet more favourable in patients with mild/moderate motor impairments who received AOT, in contrast with patients carrying similar disabilities who received the other two treatments. This suggests that AOT might be more effective in this subgroup of patients, perhaps because the integrity of their mirror neurons system (MNS) was more preserved, as indexed by EEG recording from central electrodes during action observation. In conclusion, AOT may reveal an effective rehabilitative tool in patients with subacute stroke; the EEG evaluation of MNS integrity may help to select patients who could maximally benefit from this intervention.

The effect of action observation combined with high-definition transcranial direct current stimulation on motor performance in healthy adults: A randomized controlled trial

Action observation (AO) can improve motor performance in humans, probably via the human mirror neuron system. In addition, there is some evidence that transcranial direct current stimulation (tDCS) can improve motor performance. However, it is yet to be determined whether AO combined with tDCS has an enhanced effect on motor performance. We investigated the effect of AO combined with high-definition tDCS (HD-tDCS) targeting the inferior parietal lobe (IPL) and inferior frontal gyrus (IFG), the main aggregates of the human mirror neuron system, on motor performance in healthy adults and compared the immediate vs. 24-h retention test effects (anodal electrodes were placed over these regions of interest). Sixty participants were randomly divided into three groups that received one of the following single-session interventions: (1) observation of a video clip that presented reaching movement sequences toward five lighted units + active HD-tDCS stimulation (AO + active HD-tDCS group); (2) observation of a video clip that presented the same reaching movement sequences + sham HD-tDCS stimulation (AO + sham HD-tDCS group); and (3) observation of a video clip that presented neutral movie while receiving sham stimulation (NM + sham HD-tDCS group). Subjects' reaching performance was tested before and immediately after each intervention and following 24 h. Subjects performed reaching movements toward units that were activated in the same order as the observed sequence during pretest, posttest, and retest. Occasionally, the sequence order was changed by beginning the sequence unexpectedly with a different activated unit. Outcome measures included mean Reaching Time and difference between the Reaching Time of the unexpected and expected reaching movements (Delta). In the posttest and retest, Reaching Time and Delta improved in the AO + sham HD-tDCS group compared to the NM + HD-sham tDCS group. In addition, at posttest, Delta improved in the AO + active HD-tDCS group compared to the NM + sham HD-tDCS group. It appears that combining a montage of active HD-tDCS, which targets the IPL and IFG, with AO interferes with the positive effects of AO alone on the performance of reaching movement sequences.

Activity of Mirror Neurons and Its Effect on Various Diseases

Ayna nöronların nöroanatomik yapılanması ve işlevselliğinin araştırılması son yıllarda oldukça artmıştır. Özellikle nörolojik ve ortopedik hasta gruplarında uygulanan tedavi yaklaşımlarında pasif uygulamalar yerine hastanın katılımının olduğu aktif uygulamalar tercih edilmektedir. Bunun temel sebeplerinden birisi ayna nöronları ve birincil motor korteksi dâhil ederek tedaviyi kalıcı hale getirmeyi amaçlamaktır. Ayna nöronların fonksiyonel ve disfonksiyonel durumlarını ortaya koymak, tedavi seanslarında hastaların semptomlarını anlamada çok büyük katkı sağlamaktadır. Özellikle ayna nöronları aktive ederek planlanan ayna terapisi ile hastalar nöronal bağlantılarını yeniden yapılandırarak nöroplastik aktivite sağlarlar ve böylece iyileşme süreçlerine katkıda bulunmuş olurlar. Literatür taramalarında ayna nöronların aktivasyonlarının yer aldığı hastalıkların yapısal özellikleri birbirinden farklı olsa da ortak özellik olarak ayna nöronların aktive edilerek tedaviye katkı sağladığını söylemek mümkündür. Yapılan tedavi uygulamalarında, ilgili fonksiyonel hareketin hasta tarafından fiziksel olarak yapılmadığı durumlarda dahi bilişsel olarak hareketin yapıldığının imgelenmesi, ayna nöronları aktive ederek hastanın iyilik halini arttırdığı belirlenmiştir.