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Objective To study the topography and neurophysiological differences in cortical motor representations of hand flexor and extensor muscles during motor imagery (MI). Methods Seven healthy volunteers (age 27 ± 3.4) were enrolled. Navigated transcranial magnetic stimulation was performed for mapping mm. Flexor digitorum superficialis, extensor digitorum communis cortical areas at rest and during MI (fingers flexion or extension). We assessed cortical excitability changes by the dynamics of motor threshold (MT) and paired stimuli with interstimulus intervals 2 ms (SICI) and 12 ms (ICF). Results The localization of flexor and extensor “hotspots” was different with a range of 1 cm. MT decreased during MI significantly from 50% to 47% at the flexor hotspot and from 47% to 46% at the extensor hotspot compared to resting state. There was observed the decrease of ICF during MI of both movements compared to resting state. SICI was reduced during imagery of flexion and enhanced during imagery of extension movement. Conclusions Further we will train the participants to imagine hand extension with brain–computer interface with evaluation the neurophysiological difference between trained and untrained. Topographic and neurophysiological differences of cortical motor representations of differentiated movements during MI can be the basis of new non-invasive brain–computer interface approach.

Objective To evaluate cortical plasticity processes induced by neurorehabilitation procedures and use of multimodal exoskeleton complex Methods 14 chronic stroke patients (mean age 57.5 ± 18.1 years, mean postsroke time 14.2 ± 9.9 months) were included. All patients trained 5 times per week for 2 weeks on multimodal exoskeleton complex and standardized physical therapy. Cortical plasticity processes were evaluated before and after trains by functional magnetic resonance imaging (fMRI) and navigated transcranial magnetic stimulation (nTMS). For fMRI we developed paradigm simulated reference load when walking. nTMS was performed for mapping leg cortical area. We evaluate rest motor threshold (RMT) and area’s squares for both tibialis anterior muscles. For clinical assessment we use a Fugl-Meyer Scale and 10 m walked test. Results No significant differences in clinical scales, RMT were found. Opposite directional changes in leg motor areas’ square (increase in affected hemisphere (before: 19.5 ± 22.2 mm 2 ; after: 22 ± 17.7 mm 2 ) and decreased in healthy hemisphere (before: 41.2 ± 24.9 mm 2 ; after: 39.2 ± 30.8 mm 2 ) were observed. In fMRI study the increase of activation zones in both SM1 and SMA and decrease of activation in both S2 were detected. Functional connectivity changes were founded: additional connections formation in the both hemispheres, and statistically significant interhemispheric connections between the primary motor cortex. Conclusions Founded changes in cortical plasticity can be the basics of future walking improvement.

Stroke is one of the most disabling diseases of the nervous system. Search for new approaches to stroke rehabilitation is an important clinical challenge. Among several noninvasive brain stimulation techniques repetitive transcranial magnetic stimulation (rTMS) demonstrated beneficial effect for motor recovery after stroke. Now there are two main therapeutic strategies of brain stimulation for motor rehabilitation in stroke patients: up-regulation of excitability of the primary motor cortex (M1) of the affected hemisphere (HS) with high-frequency stimulation and/or inhibition of the M1 of the unaffected HS with low-frequency stimulation. The transcranial magnetic stimulation with MRI navigation (nTMS) permits to take into account individual brain anatomy and to repeat stimulation focally. So, we supposed that for rTMS of the primary motor areas for stroke rehabilitation neuronavigation also may improve the results. The randomized blind sham-controlled study of repetitive navigated TMS of primary motor cortex for motor stroke rehabilitation was started. Design We plan to include 100 patients in this research. Primary Outcome Measures: evidence of clinically definite ischemic stroke confirmed by CT or MRI; emergence of epileptic seizures. Secondary Outcome Measures: evaluation of the clinical condition of the patients. Clinical condition of patients including motor deficit was assessed with a battery of scales: Fugl-Meyer scale, Ashworth scale, Perry scale, test with 10 meters walking, Bartel index, Renkin scale. Patients were randomly assigned to one of the four groups in the study: 1. Experimental: Low-frequency: 1 Hz, 100% Motor threshold (MO), 20 min, unaffected hemisphere. 2. Experimental: High frequency stimulation: 10 Hz, 80% MT, 2 s-stimulation, 58 s-rest-8 session; affected hemisphere. 3. Experimental: Both hemispheric stimulation: low-frequency to unaffected hemisphere than high-frequency to affect hemisphere. 4. Sham stimulation group: standard treatment and sham transcranial magnetic stimulation. Patients were not aware of the stimulation regimen. Inclusion Criteria: stroke from 8 days to 3 years in a pool of carotid arteries. NIHSS from 5 to 20 points. Rankin scale at most 3. Exclusion Criteria: implanted pacemaker, intracardiac catheters, electronic pumps, pregnancy or possibility of pregnancy in women of reproductive age; presence of metallic elements or implants in the head region; epilepsy or seizures in anamnesis. It has been recruited 15 patients until now: 3 patients in the sham group; 6 patients in the first group and 6 in the second experimental group. Mean age was 56.6 ± 9.7 years. Results Headache appeared at 5 patients after stimulation which held itself. Four patients had an increase of epileptiform discharges on EEG after 10 sessions. Secondary generalized epileptic seizure occurred in 1 patient during single pulse diagnostic TMS (3 months after the stroke in the middle cerebral artery region). Preliminary results show the relief of the post-stroke spasticity and pain after high-frequency stimulation of the affected M1. Motor improvement was demonstrated for low-frequency stimulation of the unaffected M1. Conclusion Repeated nTMS is safe and effective add-method in motor post-stroke rehabilitation, but continuous study and forming protocols are necessary to validate this method. ClinicalTrials.gov Identifier: NCT01652677.