Michael A. Piradov

Research center of Neurology · ICU

Studying rhythmic neural synchronization (cross-frequency coupling in various ranges) is an emerging topic in present-day neurophysiology. One of the best-studied cross-frequency couplings is theta-gamma phase-amplitude coupling that contributes to the cognitive function and may vary in patients with several conditions associated with cognitive imp...

Metaplasticity (plasticity of synaptic plasticity) is defined as a change in the direction or degree of synaptic plasticity in response to preceding neuronal activity. Recent advances in brain stimulation methods have enabled us to non-invasively examine cortical metaplasticity, including research in a clinical setting. According to current knowled...

The use of metaplasticity-based intermittent theta-burst stimulation (iTBS) protocols including several stimulation blocks could be a possible approach to increasing stimulation effectiveness. Our aim was to investigate the neurophysiological effects of two protocols with a short and a long interval between blocks. Seventeen healthy volunteers rece...

The existing system of medical care for patients with acute cerebrovascular accident of atherothrombotic genesis, namely lipid metabolism disorders, the modern evidence base for lipid-lowering therapy in this category of patients and the feasibility of interdisciplinary interaction of cardiologists and neurologists were discussed at a meeting of th...

Transcranial direct current electrical stimulation (tDCS) is an intensely developing area in noninvasive neuromodulation. Despite large numbers of published studies, data on the possible clinical applications of the method are contradictory. One limitation of tDCS is the relatively non-local nature of stimulation using the standard montage. High-de...

Background. Trigeminal neuralgia is the most common cause of facial pain. Insufficient effectiveness and frequent side effects of pharmacological therapy, as well as the risk of complications of invasive neurosurgical manipulations, determine the relevance of the development of new treatment approaches, one of which is repetitive transcranial magne...

Introduction: Dementia is currently one of the leading causes of mortality globally, and mortality due to dementia will likely increase in the future along with corresponding increases in population growth and population aging. However, large inconsistencies in coding practices in vital registration systems over time and between countries complica...

Objective : linguistic and cultural adaptation of the original version of Berg Balance Scale (BBS) and assessment its psychometric properties. Patients and methods . The staff of the Validation Center of International Scales and Questionnaires of the Research Center of Neurology received consent from Katherine Berg to validate the BSS in Russia. We...

Repetitive transcranial magnetic stimulation (rTMS) is an alternative treatment option for patients with drug-resistant trigeminal neuralgia (TN). However, the effect of rTMS is variable. The aim of this study was to find neuroimaging biomarkers of clinical efficacy of navigated rTMS. Seventeen patients with TN (14 women and 3 men, median age 56 ye...

INTRODUCTION Determination of the degree of depression of consciousness in patients with brain damage upon admission to the intensive care unit and intensive therapy is a primary task. In order to carry out a quick and at the same time sufficiently complete assessment of this kind, in 1974 neurosurgeons Graham Teasdale and Bryan Jennett from the Un...

Insight is the sudden unpredictable appearance of a problem’s solution. The solution of anagrams is one of the tasks available for studying insight. Repetitive transcranial magnetic stimulation (rTMS) allows the detection of a causal relationship between the activity of a cerebral cortex area and the studied cognitive phenomenon. During online-rTMS...

Chronic disorders of consciousness (DOC; i.e., vegetative state and minimally consciousness state) develop in patients surviving coma after severe brain damage. Characteristic clinical feature of these syndromes is the dissociation between preserved wakefulness and complete or almost complete absence of awareness. Advanced diagnostic technologies p...

The detection of conscious awareness in patients with disorders of consciousness using behavioral signs is challenging in the presence of sensory, motor, or executive function deficits. Brain signal measurements provide additional information for patient stratification, and the large amounts and multidimentional nature of the obtained data motivate...

Objective. To run a parallel placebo-controlled trial to assess the effects of navigated combined high-frequency rhythmic transcranial magnetic stimulation (rTMS) of the primary motor (bilateral) and left dorsolateral prefrontal cortex on the clinical dynamics of the symptoms of Parkinson’s disease (PD). Materials and methods. A total of 46 patient...

Chronic disorders of consciousness (DOC) develop after severe traumatic and non-traumatic brain damage and are characterized by the restoration of wakefulness in a patient after a coma without the recovery of consciousness. To optimize the diagnosis and treatment of patients with chronic DOC, a Russian working group on the problems of chronic DOC w...

Objective: To perform linguistic and cultural adaptation of the Fugl-Meyer Assessment of Physical Performance. Materials and methods: The study for assessment of psychometric properties included 53 post-stroke patients with neurological deficit presented by hemiparesis of different severity. The patients were assessed twice: at admission and aft...

Introduction. The widespread use of transluminal balloon angioplasty with stenting of the internal carotid arteries as part of the prevention of ischemic stroke has led to an increase in the number of publications in the world literature indicating the development of carotid sinus syndrome (“hemodynamic instability”) in the perioperative period, ce...

Background and Purpose: Despite continuing efforts in the multimodal assessment of the motor system after stroke, conclusive findings on the complementarity of functional and structural metrics of the ipsilesional corticospinal tract integrity and the role of the contralesional hemisphere are still lacking. This research aimed to find the best com...

Ischemic stroke (IS) and type 2 diabetes mellitus are factors that a ff ect the homeostasis of low-molecularweight aminothiols (cysteine, homocysteine, glutathione etc.). It has already been shown that IS in the acute period led to a decrease a level of reduced forms of aminothiols, but it is not clear whether type 2 diabetes mellitus has a noticeab...

Introduction. White matter hyperintensity (WMH) is a neuroimaging age-related phenomenon associated with an increased cardiovascular risk in people with arterial hypertension (AH). The prevalence of WMH and its relationship with risk factors for cerebrovascular disease (CVD) in middle-age population requires clarification. Aim: to assess the preval...

Background: Balance dysfunction is one of the most common problems in older people. Nevertheless, there is no objective tool for assessing psychophysiological indicators of adaptation of functional systems of the brain, and the effect of training in a virtual environment on neurodynamic processes has not been sufficiently studied. Aims: To study th...

Due to the slowing of the neurodynamic and cognitive processes, as well as changes in the musculoskeletal system that accompany aging, attention, reaction, and movement coordination are impaired in elderly patients. Decreased overall brain adaptability leads to an increased risk of falls and disability, thus reducing the age of active aging. Accord...

The difficulties of behavioral evaluation of prolonged disorders of consciousness (DOC) motivate the development of brain-based diagnostic approaches. The perturbational complexity index (PCI), which measures the complexity of electroencephalographic (EEG) responses to transcranial magnetic stimulation (TMS), showed a remarkable sensitivity in dete...

Insight is one of the most mysterious problem-solving phenomena involving the sudden emergence of a solution, often preceded by long unproductive attempts to find it. This seemingly unexplainable generation of the answer, together with the role attributed to insight in the advancement of science, technology and culture, stimulate active research in...

Major depression is a common mental disorder predominantly affecting working population and being one of the main causes of the “global burden of disease”. The lack of effectiveness of existing pharmaco􏲤 and psychotherapeutic approaches determines the high relevance of developing and implementing new effective and safe methods of treatment using no...

Transcranial magnetic stimulation (TMS) is one of rehabilitation approaches for patients with chronic disorders of consciousness (DOC). The aim of our study was to assess neurotrophic factors and the changes of those after TMS course in patients with chronic DOC. We enrolled 26 patients with chronic DOC of various etiology and 21 heathy volunteers....

The key factor promoting post-stroke gait disturbances is motor impairment of the ankle joint (AJ) which results in pathological synergies. Robotic devices used for gait training are equipped with hip and knee joint actuators. However, there is no consensus in the literature on their effect on AJ movements. The aim of this study was to investigate...

Transcranial magnetic stimulation (TMS) is an intensively developing method of non-invasive brain stimulation. TMS is widely used in cognitive neuroscience to study the causal role of various cortical areas in visual perception, memory, attention, speech, and other cognitive functions. The article discusses the general principles and main direction...

Obesity is a pathological condition caused by overweight and requiring medical intervention. The clinical and scientific experience gained over the past decades has allowed researchers to consider this problem as an independent disease with its own pathophysiological features, prevalence, incidence, approaches to therapy and prevention. One of the...

Spasticity after stroke is a factor that causes disability and restricts activities of daily living, and presents a problem for both doctors and patients’ relatives. At the present time, the Modified Ashworth scale (MAS) is a useful method of assessing increased muscle tone in patients after a cerebrovascular incident. The aim of the work is the li...

Introduction. To date, patients with chronic disorders of consciousness (CDC) represent a serious problem from the medical, social, and economic points of view. Because of the relatively small incidence of this condition, accumulation of the sufficient experience in its diagnosis and treatment remains a complex task, while the lack of a unified app...

It has been proposed that the effectiveness of non-invasive brain stimulation (NIBS) as a cognitive enhancement technique may be enhanced by combining the stimulation with concurrent cognitive activity. However, the benefits of such a combination in comparison to protocols without ongoing cognitive activity have not yet been studied. In the present...

Despite intensive study, the data regarding functional role of specific brain regions in the working memory processes still remain controversial. The study was aimed to determine the activation of cerebral cortex regions at different stages of the working memory task (information encoding, maintenance and retrieval). Functional magnetic resonance i...

Background. Carpal tunnel syndrome is the most common tunnel neuropathy in which the median nerve is compressed at the level of the wrist in the carpal canal. Treatment of carpal tunnel syndrome can be conservative and surgical. Surgical treatment is indicated in case of ineffective conservative treatment. However, the strategy of managing patients...

A rare case of acute necrotizing encephalitis associated with influenza virus in an adult man is described. This clinical case is one of the few published cases in the world literature and the only one in the Russian literature.

Objective: To evaluate therapeutic effects of navigational dual-target high-frequency rTMS over the primary motor (M1, bilateral) and the left dorsolateral prefrontal cortex (DLPFC) on clinical dynamics of Parkinson's disease (PD) symptoms in a parallel placebo-controlled study. Material and methods: The study included 46 patients randomized int...

Objective: To evaluate the hemostasis of plasma aminothiols in different subtypes of ischemic stroke (IS). Material and methods: The study included 177 patients, aged 62 (55-68) years, admitted in the first 8-24 hours since IS onset. The pathogenetic subtype of IS was clarified according to the results of clinical and instrumental examination by...

Objective: To study diagnostic and therapeutic values of transcranial magnetic stimulation (TMS) in writing cramp (WC). Material and methods: Twelve right-handed patients with WC were enrolled in the study. All patients underwent low-frequency repetitive TMS (rTMS) of the premotor cortex of contralateral to affected hand hemisphere. The clinical...

Background and Purpose Despite the continuing efforts in multimodal assessment of the motor system after stroke, conclusive findings on the complementarity of functional and structural metrics of the corticospinal tract (CST) integrity and the role of the contralesional hemisphere are still missing. The aim of this work was to find the best combina...

Hypertension (HT) and its cerebral complications are extremely vexing medical and social problems. Despite the obvious association between hypertension and the clinical and neuroimaging features of cerebral microangiopathy (CMA) (also known as cerebral small vessel disease), the causal links between them remain ambiguous. Besides, antihypertensive...

High-frequency repetitive transcranial magnetic stimulation (rTMS) is approved by the Food and Drug Administration (FDA) for the treatment of pharmacotherapy-resistant depressive disorders (DD). Individual target determination for stimulation can be one of the approaches that can increase the efficiency of the technique. Objective: to compare of th...

Objectives. To assess the efficacy of using a brain–computer interface with a hand exoskeleton (BCI–exoskeleton) in the complex rehabilitation of patients with the sequelae of cerebrovascular accidents and to determine the minimally adequate reserves of cognitive functions required for the patient to carry out effective mental training using the mo...

Introduction. The assessment of the level of consciousness in patients with acute brain injury is a mandatory first step of neurological examination. There is a need for clinical scales which allow to assess the level of wakefulness and degree of patient non-responsiveness in 23 minutes. The Full Outline of UnResponsiveness (FOUR) scale is an optim...

Motor function deficit due to stroke is one of the leading causes for disability among working-age population. The most effective evidence-based treatment strategies are task oriented exercise approaches including constrained-induced movement therapy. Robot-assisted training provides high amount of repetitions and feedback to patient. Adjuvant ther...

According to the literature data, only 5–20% of post-stroke patients are able to restore the hand motor function completely. Correct goal setting and individual approach to the patient's functional recovery are important. Our study aimed to develop an algorithm of impaired hand motor functioning assessment for post-stroke patients and to determine...

Motor evoked potentials (MEPs) caused by transcranial magnetic stimulation (TMS) provide a possibility of noninvasively mapping cortical muscle representations for clinical and research purposes. The interpretation of such results is complicated by the high variability in MEPs and the lack of a standard optimal mapping protocol. Comparing protocols...

Background Transcranial direct current stimulation (tDCS) is a promising method for motor recovery in patients with stroke. At present different electrodes montages are used in motor stroke, but their comparative efficacy remains unclear. The aim of this study was to evaluate efficacy of different tDCS montages in chronic motor stroke. Materials a...

Background Navigated transcranial magnetic stimulation enables noninvasive mapping of muscle cortical representations for research and clinical purposes. Several mapping protocols are in use, with no consensus regarding the optimal one and insufficient data about their influence on the mapping accuracy. We aimed to determine this influence for prot...

Background The search for biomarkers in amyotrophic lateral sclerosis (ALS) can provide pathophysiological insights and is important for early diagnosis and monitoring of the disease progression. Mapping muscle cortical representations using navigated transcranial magnetic stimulation (nTMS) is a noninvasive method for probing corticospinal excitab...

Background Trigeminal neuralgia (TN) is one of the most common causes of chronic neuropathic pain. Chronic pain is currently seen as a result of impaired interaction between different brain structures that provide pain processing. We aimed to assess functional brain abnormalities in TN by an analysis of connectivity using resting-state fMRI. Metho...

Background Repetitive transcranial magnetic stimulation (rTMS) is used in both clinical practice and basic research. The aim of our study was to investigate rTMS tolerability using standardized questionnaires. Materials and methods 69 patients (vascular mild cognitive impairment – 36, recurrent depression – 13, post-stroke pain – 8, trigeminal neu...

Background: Clinical efficacy of rTMS in recurrent depression (RD) is highly variable. It is important to search for approaches improving the efficacy, and choosing the target based on functional connectiv- ity (FC) is promising. We aimed to compare the effects of the stan- dard and FC-based rTMS targeting in RD patients. Methods: 30 pharmacoresist...

Competition for resources is a fundamental characteristic of evolution. Auctions have been widely used to model competition of individuals for resources, and bidding behavior plays a major role in social competition. Yet how humans learn to bid efficiently remains an open question. We used model‐based neuroimaging to investigate the neural mechanis...

Objectives: To determine the disruption of low-molecular-weight aminothiols (LMWTs: cysteine, cysteinylglycine, homocysteine, and glutathione) homeostasis in blood plasma during the acute and early subacute stages after ischemic stroke. Patients and methods: We admitted 41 patients with primary large-artery atherosclerosis and cardioembolic stro...

Diagnostic accuracy of different chronic disorders of consciousness (DOC) can be affected by the false negative errors in up to 40% cases. In the present study, we aimed to investigate the feasibility of a non-Gaussian diffusion approach in chronic DOC and to estimate a sensitivity of diffusion kurtosis imaging (DKI) metrics for the differentiation...

Background: Navigated repetitive transcranial magnetic stimulation (rTMS) is a promising tool for neuromodulation. In previous studies it has been shown that the activity of the default mode network (DMN) areas, particularly of its key region-the angular gyrus-is positively correlated with the level of consciousness. Our study aimed to explore the...

Motor rehabilitation is one of the key tasks for the recovery of personal independence of patients suffering a stroke. Neuromuscular electrostimulation synchronized with the performance of a motor task, known as functional electrical stimulation (FES), is a proven and widely used method. Specialists have established the principles of safe neuromusc...

Navigated transcranial magnetic stimulation (nTMS) mapping of cortical muscle representations allows noninvasive assessment of the state of a healthy or diseased motor system, and monitoring changes over time. These applications are hampered by the heterogeneity of existing mapping algorithms and the lack of detailed information about their accurac...

Navigated TMS mapping of cortical muscle representations allows noninvasive assessment of the state of a healthy or diseased motor system and monitoring its change with time. These applications are hampered by the heterogeneity of existing mapping algorithms and the lack of detailed information about their accuracy. We aimed to find an optimal moto...

Rhythmic transcranial magnetic stimulation (rTMS) is a non-invasive method for brain stimulation, widely used in the treatment of various diseases and in research. In this regard, the problems of rTMS safety and tolerability are becoming especially relevant. Most studies describe only serious side effects of rTMS, which, in fact, are extremely rare...

Background: The number of individuals living with dementia is increasing, negatively affecting families, communities, and healthcare systems around the world. A successful response to these challenges requires an accurate understanding of the dementia disease burden. We aimed to present the first detailed analysis of the global prevalence, mortalit...

BACKGROUND: The number of individuals living with dementia is increasing, negatively affecting families, communities, and health-care systems around the world. A successful response to these challenges requires an accurate understanding of the dementia disease burden. We aimed to present the first detailed analysis of the global prevalence, mortali...

Aim: To assess diagnostic and therapeutic values of transcranial magnetic stimulation (TMS) in patients with writer's cramp (WC). Material and methods: Twelve right-handed patients with WC were enrolled in the study. All patients underwent low-frequency repetitive TMS (rTMS) over the premotor cortex of the hemisphere contralateral to the affecte...

The authors describe a rare clinical case of non-fatal acute necrotizing encephalitis associated with influenza virus in an adult man. This clinical case is one of the few cases published in the world literature and the only one in the Russian literature.

Objective : to develop a Russian version of the modified Rankin Scale (mRS) and to assess its psychometric properties. Patients and methods . The investigation involved 50 patients (25 women, 25 men) over 18 years of age (mean age, 56 years) with an acute cerebrovascular accident diagnosis. During the validation procedure, the authors carried out t...