Ekaterina Sergeevna Ikonnikova

BACKGROUND: Currently, the use of transcranial direct current stimulation (tDCS) is being actively studied as a rehabilitation method for patients with various central nervous system diseases. Only a few studies have investigated the use of this technique in patients with hereditary ataxias, which limits its application as a routine rehabilitation method. However, this study demonstrates the promising potential of these methods for treating patients with hereditary cerebellar ataxias. Thus, an important task is the development and testing of a tDCS protocol, as well as the evaluation of its effectiveness in patients with hereditary cerebellar ataxias. AIM: Evaluation of the effectiveness of a new tDCS protocol for motor rehabilitation in patients with hereditary cerebellar ataxias. METHODS: The study included 20 patients: 7 men and 13 women; the median age was 51.5 [44; 58.5] years. All patients underwent a course of 10 tDCS sessions according to an original protocol. The effect on mobility and balance functions was assessed using clinical scales (Berg Balance Scale, Timed Up and Go test and 10 Meter Walk Test) and stabilometric assessment (Romberg test, static and dynamic tests). The effect on the severity of ataxia symptoms was assessed using the SARA and ICARS clinical scales. RESULTS: There was a significant improvement in mobility, as measured by the Timed Up and Go test, and in balance, as measured by the Berg Balance Scale (p 0.05). Stabilometric assessment confirmed an improvement in static balance function. Following the stimulation course, a decrease in the severity of ataxia symptoms was also observed, attributed to a reduction in static-locomotor impairments and limb movement disturbances. CONCLUSION: Thus, our study showed the efficacy of the developed tDCS protocol for the rehabilitation of gait, mobility, and balance disorders in patients with hereditary ataxias.

Background. Although a significant number of studies have focused on the rehabilitation of children patients with cerebral palsy (CP), the use of restorative treatment in the adult population with this pathology remains understudied. High-technology robot-assisted rehabilitation using exoskeleton systems for gait restoration has proven effective in various neurological disorders, including the rehabilitation of children with CP. However, questions concerning the application of these methods in adult patients require further clarification. Aim. To investigate the effect of robot-assisted gait training in an exoskeleton in an outpatient setting on mobility, gait speed, and gait biomechanics in adult patients with CP (students of an inclusive university), and to determine the feasibility and effectiveness (i.e., the appropriateness) of outpatient motor rehabilitation using such training for this patient population. Materials and methods. The study included 11 patients with spastic CP (spastic diplegia), classified as Gross Motor Function Classification System levels II–III. All patients underwent 10 training sessions on the Remotion robotic exoskeleton system (JSC "Volzhsky Electromechanical Plant", Russian Federation) once a day, 5 days a week. Clinical assessment included the timed up and go test and the 10-meter walk test. To objectify the clinical assessment data, biomechanical analysis of cyclic walking was performed using the Biomekhanika Nevrokor system (LLC Nevrokor, Russian Federation). Results. The study demonstrated a clinically significant improvement in mobility as assessed by the timed up and go test (p 0.05) and in fast walking speed measured by the 10-meter walk test (p 0.05). Based on the gait biomechanics analysis, the patients were divided into two groups: a symmetric gait group (n = 5) and an asymmetric gait group (n = 5). In the asymmetric gait group, a statistically significant improvement in step phase symmetry was observed after the rehabilitation course using the Remotion exoskeleton system. These changes occurred due to a reduction in compensatory movements at the hip joint and normalization of the phase characteristics of the flexion/extension angles of the lower limb joints. Conclusion. The present study confirmed that outpatient motor rehabilitation using robot-assisted therapy with an exoskeleton system is feasible, appropriate, and effective in adult patients with a previously established diagnosis of CP who are continuing their higher education.

Introduction. Gait disorders are a common and severe consequence of stroke, limiting patient autonomy and quality of life. A functional near-infrared spectroscopy (NIRS)-based brain–computer interface (BCI) represents a promising technology for restoring motor functions; however, its application in gait rehabilitation remains insufficiently studied. Study aim: To evaluate the clinical applicability and technical feasibility of an NIRS-based BCI technology combined with a pneumatic plantar support load simulator (pneumatic orthosis) as an adjunct to comprehensive motor rehabilitation in post-stroke patients. Materials and methods. Seventeen patients were enrolled in the pilot study, of whom 15 (median age 58.0 [47.0; 64.0] years, median time since stroke 6.0 [3.0; 9.0] months) completed a course of 7–13 (median 10 [9; 10]) training sessions with the NIRS-BCI–pneumatic orthosis technology in addition to a comprehensive motor rehabilitation program. Motor function was assessed using the Fugl–Meyer Assessment scale for the lower extremity, the 10-Meter Walk Test, and the Timed Up and Go test. Results. A total of 147 NIRS-BCI–pneumatic orthosis training sessions were conducted, with a total median exposure of 229 minutes per patient. The median BCI classifier recognition rate for patients’ mental states was 54.93% [53.10; 69.70]. The median of the maximum achieved recognition rates was 75.57% [67.54; 87.14]. Characteristic hemodynamic activation patterns were identified in motor and associative cortical areas. Following the course, statistically significant improvements were noted on the Fugl–Meyer Assessment scale (from 19.0 [16.0; 24.0] to 24.0 [20.0; 25.0] points; p = 0.001) and the Timed Up and Go test (from 17.61 [14.21; 22.34] to 16.06 [13.00; 17.41] s; p = 0.041), but not on the 10-Meter Walk Test (p 0.05). Most patients tolerated the procedures satisfactorily; two participants withdrew early. Conclusion. The clinical applicability and technical feasibility of the NIRS-BCI–pneumatic orthosis technology for post-stroke gait rehabilitation have been confirmed. Randomized controlled trials are required to assess its clinical efficacy.

The effectiveness of forming a new fine motor coordination skill, hook-based wire maze tracing, on a hand muscle bioelectrical activity was studied using three training programs: (a) specific maze coordination training, (b) single-session training of discrete relaxation capability in forearm pronators and supinators, and (c) combined practice of maze tracing and discrete relaxation exercises in healthy volunteers (n = 32). According to the training regimens (10 sessions of 30 min per day in the laboratory), four groups were formed: “Coordination” (n = 8), “Relaxation” (n = 8), “Combined” (n = 8), and “Control” (n = 8). Skill acquisition efficiency was assessed by the number of errors and the length of the maze path completed within 3 min. Electromyographic activity of seven muscles (m. pronator teres, supinator, trapezius, biceps brachii, triceps brachii, deltoideus, pectoralis major) during maze tracing was recorded using a wireless Delsys EMG system (Delsys Trigno EMG) integrated with the Vicon motion capture system (Nexus 2.12). It was found that the trained skill improved only in the Coordination and Combined groups, as reflected by a reduction in the number of errors by –62% (p < 0.01) and –55% (p < 0.01), and an increase in the completed maze path length by 53% (p < 0.05) and 69% (p < 0.05), respectively. This confirms the concept of high specificity in complex motor learning. Skill refinement led to two key shifts in muscle activity, also in the Coordination and Combined groups: (1) a significant decrease in the activity of proximal musculature (m.m. trapezius, deltoideus, pectoralis major), which is responsible for shoulder girdle stabilization; (2) a parallel optimization of distal coordination: a reduction in excessive activity of antagonists during pronation (m. biceps brachii) and supination (m. pronator teres), as well as of the agonist during pronation. This reorganization of muscle activity reflects a transition from less efficient control with excessive joint stiffness to differentiated and predictive control, ensuring precision and economy of distal hand movements. The obtained data can be used to improve the training of complex coordination skills in sports and to plan rehabilitative training programs in neurorehabilitation.

Transcranial magnetic resonance–guided focused ultrasound is a rapidly evolving noninvasive treatment modality for neurological disorders associated with movement disturbances. The greatest clinical experience has been accumulated in patients with essential tremor and Parkinson disease. Despite the minimally invasive nature of this intervention, adverse effects have been reported, including postural imbalance, which may occur in 75%–90% of cases. The most pronounced disturbances are detected in patients undergoing high-energy exposure, as well as in patients with extension of the treatment area into the subthalamic region. The present clinical observation describes the characteristics of balance disturbances and changes in gait biomechanics in a 63-year-old patient with pharmacoresistant essential tremor who underwent focused ultrasound brain surgery. As part of the preoperative assessment, magnetic resonance imaging and computed tomography of the brain were performed; based on computed tomography findings, the skull density ratio was calculated. Given the low skull density ratio, modification of the standard magnetic resonance–guided focused ultrasound protocol was performed. In the postoperative period, following high-energy exposure in the region of the left ventral intermediate nucleus of the thalamus with extension into the posterior subthalamic region, regression of tremor in the right extremities was noted; however, clinical assessment of the patient’s condition, as well as comparative stabilometric analysis in the preoperative and postoperative periods, demonstrated alterations in balance and gait. Thus, on the one hand, the unequivocal efficacy of the focused ultrasound method in essential tremor is clearly demonstrated; on the other hand, the possibility of adverse events is evident, which, despite regression of the main clinical manifestation of the disease, may lead to insufficient patient satisfaction with treatment. Further studies will help identify factors leading to balance disturbances, improve the selection of patients for focused ultrasound interventions, and develop fall-prevention programs aimed at reducing gait and balance disorders in this patient population.

Background. The main clinical manifestation of hereditary cerebellar ataxias is a progressive loss of motor coordination and balance, leading to a reduced quality of life increased risk of falls. Balance impairments in patients are assessed using both general clinical and specialized scales, which allow for a detailed characterization of symptoms. Aim. To investigate the clinical and stabilometric parameters of balance and risk factors for falls in patients with hereditary cerebellar ataxias. Materials and methods. The study included 38 patients with hereditary cerebellar ataxias and 22 healthy volunteers in the control group. To assess balance impairments, mobility, and fall risk, general clinical scales (the Timed Up and Go (TUG) test, the Berg Balance Scale (BBS), the 10-meter walk test) and specific scales (the Scale for the Assessment and Rating of Ataxia (SARA), the International Cooperative Ataxia Rating Scale (ICARS)) were used. Stabilometric parameters were recorded using the ST-150 platform. Based on the clinical scales, patients were stratified according to their risk of falls. Results. When stratifying patients by fall risk, the use of general clinical scales led to different risk level classifications: according to the TUG test, the majority of patients (65 %) had a low risk, while according to the BBS, 76 % were classified as high-risk. Gait analysis confirmed a decrease in comfortable and fast walking speed with an increase in fall risk, which was more pronounced when stratified by the TUG test, reflecting dynamic balance impairments. The use of specific scales (SARA and ICARS) established that ataxia symptoms worsen with an increase in fall risk, especially when grouped by the TUG test, which better reflects the clinical features of patients associated with fall risk. Stabilometric analysis revealed significant changes in static and static-dynamic balance parameters even in patients with no fall risk according to the TUG test, and also showed that the BBS is the most sensitive to these impairments. Conclusion. The combined use of the BBS and the TUG test allows for a comprehensive assessment of balance disorders and enables the personalization of rehabilitation and fall prevention programs for this patient group.

The paper provides an overview of studies on the use of movement image training and brain-computer interfaces (BCIs) for cognitive rehabilitation in patients with neurological diseases. Based on the analysis of studies published from 2004 to 2025, the effectiveness of these methods in recovering cognitive functions in patients with stroke (13 studies), Parkinson’s disease (4 studies), and multiple sclerosis (2 studies) was evaluated. Most studies demonstrated a positive effect of movement image training on the cognitive functions of patients with neurological diseases and moderate cognitive deficits. The effectiveness of this approach is comparable to that of specialized cognitive training. In studies using BCI to control movement image training, an improvement in cognitive functions was also reported. Some studies showed a positive correlation between changes in cognitive indicators and the degree of motor recovery. In groups of patients with normal or near-normal baseline MoCA scores, no significant improvement in cognitive function was reported after a training course. The heterogeneity of the analyzed studies makes direct comparison between them difficult. The results of the analysis of published studies indicate the prospect of using the movement image training with BCI control in the cognitive rehabilitation of neurological patients. However, well-designed randomized controlled trials are necessary to study the mechanisms of the ideomotor training effects on cognitive functions and to develop standardized protocols for assessing their effectiveness.

Introduction. The high prevalence of post-COVID syndrome (PCS), which frequently manifests with emotional disturbances, cognitive impairment, and asthenia, necessitates effective rehabilitation methods. One potential approach is electroencephalography (EEG)-based biofeedback (BFB) therapy, though its use in PCS management has been explored in only a few studies to date. The study aimed to evaluate the effects of EEG α-rhythm BFB training on emotional state and cognitive function recovery, and reduction of astheniа symptoms in PCS patients. Materials and methods. Patients diagnosed with U09. Post-COVID-19 condition were randomly assigned to two groups of 10 participants each. The main group underwent 12–15 sessions of EEG α-rhythm BFB training using the NeuroPlay-6C headset with the Neurocorrection of COVID-19 Psychoemotional Consequences protocol, while the control group received identical training without biofeedback. Assessments performed before and after the intervention included: emotional state evaluation (State-Trait Anxiety Inventory [STAI], Short Health Anxiety Inventory [SHAI], Beck Depression Inventory [BDI], Psychological Stress Measure [PSM-25]), cognitive function assessment (Addenbrooke’s Cognitive Examination III [ACE-III], Schulte tables, Stroop test, Tower of London test, N-back test, 10-word memory test), assessment of asthenia (Multidimensional Fatigue Inventory [MFI]), and sleep quality evaluation (Insomnia Severity Index [ISI]). Results. In both groups, the training resulted in a significant reduction of personal anxiety, psychological stress, depression, and asthenia. The main group additionally demonstrated decreased health-related anxiety and improved information retention parameters. Intergroup comparison revealed more pronounced dynamics in the main group: greater reduction of general fatigue manifestations, increased immediate word recall volume, and improved retention of verbal information in working memory. The proportion of patients transitioning to milder symptom severity levels on individual scales was comparable between both groups. Conclusion. EEG α-rhythm biofeedback training can be implemented at the outpatient rehabilitation stage for PCS patients.

Understanding patterns of interhemispheric asymmetry is crucial for monitoring neuroplastic changes during post-stroke motor rehabilitation. However, conventional laterality indices often pose computational challenges when applied to functional near-infrared spectroscopy (fNIRS) data due to the bidirectional hemodynamic responses. In this study, we analyze fNIRS recordings from 15 post-stroke patients undergoing motor imagery brain–computer interface training across multiple sessions. We compare traditional laterality coefficients with a novel task response asymmetry coefficient (TRAC), which quantifies differential hemispheric involvement during motor imagery tasks. Both indices are calculated for oxygenated and deoxygenated hemoglobin responses using general linear model coefficients, and their day-to-day dynamics are assessed with linear regression. The proposed TRAC demonstrates greater sensitivity than conventional measures, revealing significantly higher oxygenated hemoglobin TRAC values (0.18 ± 0.19 vs. −0.05 ± 0.20, p < 0.05) and lower deoxygenated hemoglobin TRAC values (−0.15 ± 0.27 vs. 0.04 ± 0.23, p < 0.05) in lesioned compared to intact hemispheres. Among patients who exhibit substantial motor recovery, distinct daily TRAC dynamics were observed, with statistically significant temporal trends. Overall, the novel TRAC metric offers enhanced discrimination of interhemispheric asymmetry patterns and captures temporal neuroplastic changes not detected by conventional indices, providing a more sensitive biomarker for tracking rehabilitation progress in post-stroke brain–computer interface applications.

Introduction. The relevance of studying balance impairment in patients with Parkinson’s disease (PD) lies in the need to prevent falls and injuries while enabling patients to maintain maximum independence and mobility. Promising advances in posture and gait screening using digital image processing require a thorough understanding of fundamental balance maintenance strategies. The study was aimed at investigating balance maintenance strategies during PD “on” and “off” periods using classical and integral stabilometric parameters. Materials and methods. The study included 27 PD patients with the median of 61 years. The mean total daily levodopa equivalent dose was 889.71 mg. All patients underwent clinical balance assessment using the Berg Balance Scale and stabilometric platform testing during “on” and “off” periods. Results. Berg Balance Scale scores revealed mild balance impairments in PD patients, with greater severity during the “off” period (p 0.05). Classical Romberg test parameters during the “on” period demonstrated deteriorated balance function and increased reliance on visual strategies for balance maintenance. Analysis of vector integral parameters during the “off” period showed a significant increase in angular velocity and coefficient of abrupt direction changes (p 0.05). Stabilometry data indicate balance impairments in both PD “on” and “off” states, accompanied by different compensatory strategies. Conclusion. Despite clinical assessments suggesting only mild balance impairments and low fall risk in PD patients, stabilometric parameters revealed more significant static balance disorders contributing to fall risk. Notably, the diagnostic value of classical stabilometric parameters decreases during the “off” period, while vector parameters characterizing balance maintenance strategies gain importance. We propose that these integral parameters can effectively assess balance quality and fundamental compensatory strategies in PD patients undergoing treatment. The findings are valuable for developing digitalized balance analysis technologies incorporating artificial intelligence.