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Background Severe traumatic brain injury (STBI) is almost always accompanied by movement disorders. The use of electroencephalography (EEG), supplemented by mathematical analysis, in combination with functional magnetic resonance imaging (fMRI) expands the possibilities of studying brain neuroplasticity as a basis for compensation post-traumatic motor disorders. Material and methods Multichannel EEG and fMRI 3T during passive motor test (hand finger clenching by experimenter) were performed in 28 patients with STBI and 17 healthy subjects. The most detailed spectral-coherent analysis of spatial EEG changes was performed in 10 patients with varying degrees of hemiparesis, but similar to the norm fMRI response. Results It was revealed that individual EEG restructurings in a passive motor test in patients with STBI are characterized by significant variability and the inclusion of the brain regions not typical for the norm. Secondary statistical analysis showed that the topography of EEG coherence changes shows the greatest correlation with the degree of hemiparesis: increased reactivity of the frontal-central areas in the ipsilateral hemisphere relative movement with mild hemiparesis and the inclusion of both hemispheres as the motor disorders increase. Localization of these changes is similar to the topography of the fronto-pontine, parietotemporo-pontine and occipito-mesencephalic motor tracts cortical projections. Conclusions This results demonstrate a greater sensitivity of EEG responses to the degree of motor defect compared with hemodynamic (fMRI). They confirm our hypothesis put forward earlier on the possible participation of the extra-pyramidal system in compensating for the post-traumatic motor defect. Supported by RFFI 18-013-00355 .

Objectives The purpose of this study is to estimate the therapeutic potential of transcranial magnetic stimulation (TMS) in patients after traumatic brain injury (TBI) with impaired consciousness and motor activity. Methods Observation groups: (1)19 patients after TBI at the age of 16–50 with a prolonged (from 60 to 360 days) unconscious state in which the rhythmic TMS was performed; (2) Control group: 6 healthy men aged 22–28. Changes of neurological status, indicators of the memory and attention, and N100, N200 and P300 components of auditory ERP hour before and hour after stimulation, the dynamics of diagnostic TMS and bimodal (somatosensory and short latency auditory) EP’s were estimated. Results Therapeutic rTMS of the sagittal premotor cortex areas in both groups concurred with improvement of any attention and normalization of amplitude and latency of all ERP components, especially for P300. rTMS of the frontal lobes facilitated positive clinical dynamics, while rTMS of the parietal lobes did not prove any clear positive effects. Conclusions The obtained data proposes the availability of using rTMS for therapeutic purposes in patients with PUS. The most promising targets for stimulation at the moment seems to be the frontal and sagittal premotor areas of the brain. Further research is required to clarify the areas and parameters of stimulation. Supported by: RFFI N 16-29-08304 .

Objectives Recovery of both mental and motor functions is one of the key problems of neurorehabilitation of patients with traumatic brain injury (TBI), accompanied by posttraumatic unconsciousness state (PUS). The purpose of pilot study is to clarify the diagnostic and therapeutic potential of TMS in patients after TBI with impaired motor activity and consciousness. Methods Observation groups: (1) 15 patients after TBI at the age of 17–56, in which the diagnostic TMS (cortical motor areas (M1) bilaterally, CVII bilaterally, registration of MEPs from musculus abductor pollicis brevis) was performed; (2) 9 patients after TBI at the age of 16–44 with a prolonged (from 60 to 220 days) unconscious state in which the rhythmic TMS was performed; (3) Control group: 5 healthy men aged 22–28. Diagnostic TMS evaluated cortical, radicular latency and amplitude of MEPs,time of central motor conduction. In the second and third groups changes of neurological status, indicators of the memory and attention, and N100, N200 and P300 components of auditory ERP hour before and hour after stimulation were estimated. Results Diagnostic TMS in patients with positive or ambiguous clinical dynamics showed initial difference of conductivity of tracts in comparison with normal data by 20–30% or 30–40%, respectively, with progressive improvement as motor and cognitive functions recovered. In patients with negative clinical dynamics TMS values had significantly larger deviation of cortical latency and amplitudes of MEPs (over 45%), and also the time of central motor conduction. Statistical analysis of acquired data revealed the greatest prognostic significance for determining the level of the amplitudes of MEPs with undeniable importance for the indicators of cortical latency and the time of central motor conduction. Therapeutic TMS of the sagittal premotor cortex areas in groups 2 and 3 concurred with improvement of any attention and normalization of amplitude and latency of all ERP components, as well as indicators of their spatial synchronism, especially for P300. Conclusions The obtained data clarifies diagnostic parameters of TMS and proposes the availability of using rTMS for therapeutic purposes in patients with PUS. Supported by RFFI N16-29-08304 .

Severe traumatic brain injury (STBI) is nearly always comes with movement disorders. Objectives Comparison of cerebral structural-functional control of movement’s opportunity and implementation in healthy volunteers and patients with various degrees of hemiparesis after STBI. Methods Observation groups: 28 patients with SOBI (main) and 17 healthy volunteers (control). 3T fMRI recorded at rest and passive right hand finger clenching (by experimenter). Individual and group analysis of Sensorimotor resting-state network and motor fMRI responses was carried out by FSL software (ICA algorithm), SPM8 and CONN. Topography and volume activated brain regions as well as brain connectivity between them were determined. Results At STBI in the majority cases without hemiparesis or with its mild degree, neuroanatomy of the rest-state sensorimotor network and “passive” motor fMRI response are close to normal. However with an increase of hemiparesis expression we have seen an asymmetric reduction of sensorimotor resting-state network and more diffuse “passive” fMRI response - with activation of nonspecific to movement brain structures: frontal and temporal cortex, cerebellar vermis and others. Discussion A comparison of the passive movement’s functional anatomy in STBI with motor system topographic anatomy indicates a variability in movement disorders compensation mechanisms based on the possible inclusion of different “functional doublers”, such as fronto-pontinus conduction tract as well as occipito–temporopontinus. This hypothesis confirmed by comparative analysis of brain connectivity within different neuroanatomical motor tracts in healthy volunteers and patients with STBI. Conclusions The retrieved data can be useful to develop individualized neurorehabilitation programs of post-traumatic motor disorders. Supported by RFFI 115-36-01038.

Introduction Repetitive transcranial magnetic stimulation (rTMS) is a promising method in treatment of patients with various neurological diseases not only transcranially, but also at other levels of the nervous system, including peripheral. Currently, there are different protocols for the treatment of patients with neurological disorders at the lumbar level, for the treatment of headache, central pain syndromes and other neurogenic disorders. Objective Goal of this pilot study was to update and adapt existing protocols of rTMS for neurological patients. Methods Therapeutical magnetic stimulation was performed in order to restore lost function or for pain relief between the two groups of observations: patients with the development of compression syndromes in the lumbar level (12 patients) and chronic headache (7 patients) and in two patients with tremor-rigid form of Parkinson’s disease. To avoid terminological confusion, the abbreviation “rTMS” in this paper is applied on the second group of patients and patients with Parkinson’s disease; for the first group, the term “rTMS” is replaced by the already adopted in the literature “rPMS” – rhythmic peripheral magnetic stimulation. After studying international experience (Le Faucheur JP et al. Evidence-based guidelines on the therapeutic use of repetitive transcranial magnetic stimulation (rTMS). Clin Neurophysiol 2014), for the first group of patients, it was decided to carry out a rhythmic low frequency stimulation of the lumbosacral (L3-S1) region, in the projection of the nerve structures, which caused motor deficit, sensory disorders, urinary retention. In the second group was used low (less than 5 Hz) and high (5–15 Hz) frequency rTMS at the nape area and left premotor area, respectively. Patients with Parkinson’s disease carried out high-frequency (8–12 Hz) RTMS to the left and right motor areas of the cerebral cortex (M1). For magnetic stimulation device was used MagPro X100 (“Medtronic”, USA) equipped with a circular coil (mcf-125), in combination with neurosensory analyzer “Viking IV” of “Nicolet” (USA) as a diagnostic system. Stimulation was carried at rates of 5–15 sessions lasting 15–35 min, 1 time per day. Results In the first group of patients after rTMS course most of them (8 of 12) subjectively noted relief of the pain syndrome. In more than 60% of cases the effect was persistent: 1.5 months after stimulation. In the second group of patients it was shown that only low-frequency rTMS of cervical-occipital region was ineffective – for 5 sessions, there was no evidence of any significant changes in patient’s status. The positive effect of reducing the intensity and duration of the headaches was noticed only after joining the high-frequency stimulation of the left premotor area (approximately after 8 sessions), which grew progressively by the end of therapy. During dynamic monitoring of patients with Parkinson’s disease positive changes in the motor functions were manifested by about 6–9 magnetic stimulation procedures (increase in muscle strength in the limbs, improvement of the accuracy of movements and improvement of fine motor skills). Thus, these results suggest a promising therapeutic application of rhythmical MS for patients in all represented groups, but verification and refinement of the effects on a larger sample of observations are required. Supported by grant RFBR # 15–29-08304.

FMRI RS analysis is adequate for basic level human brain’s functional activity study in health and pathology. However there is no recognized processing algorithm, convenient for clinic. We conducted a pilot RS studies (fMRI 3T) in 12 healthy volunteers and 6 patients with TBI with movement disorders and depression of consciousness, according ICA as implemented in FSL software. After the selection of liquor and vascular artifacts were detected 7–8 components, described as the main in literature. DMN, sensorimotor and lateralized fronto-parietal components were analyzed in more details, evaluated topography, the total volume and intensity of activation as well as power spectrum frequency characteristics of hemodynamic signals (average frequency, dominant frequency peak). It was found that activation volume and average power spectrum frequency of DMN network variative in healthy subjects and conjugate to gender, motor functional asymmetry and EEG pattern. Depression of consciousness in TBI patients accompanied by reduction of the DMN network cortical components, intensity of its activation and decrease frequency indicators. When hemiparesis we observed asymmetric reduction of sensorimotor component. These data demonstrate diagnostic informative of the used algorithm RS fMRI analysis and clarify the functional significance of individual independent components and their quantitative characteristics in TBI.

Repetitive transcranial magnetic stimulation (rTMS) is a method in treatment of posttraumatic unconsciousness states. Goal of the study was to analyze the affects on mental and bioelectric activity under low-frequency rTMS in healthy persons and patients with PUS. Two groups of participants were evaluated in view of functional sub-threshold rTMS effects on premotor cortex: (1) 5 healthy volunteers underwent placebo and single rTMS with memory, attention and AERP (N100, N200, P300) assessment prior and 1 h after stimulation; (2) 8 patients with PUS underwent single rTMS with clinical and AEP assessment; 5 of whom underwent 7-day rTMS. Clinical assessment included determination of consciousness recovery stages (Dobrokhotova et al., 1996) and functional activity scale developed by authors with focus on the attention and movement. AERP were recorded by two-stimulus oddball paradigm, in tasks of listening sounds and accounts of the target. Distinct rTMS effects on attention was revealed: (1) activization in healthy volunteers, (2) its restoration in patients. In target stimuli counting tasks (mainly voluntary attention) quantitative changes of N2 and P300 prevailed in the left frontal region. In listening sounds tasks (mainly involuntary attention) the most significant changes were recorded in P300 in the right temporal region.