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Effective connectivity based on functional magnetic resonance imaging (fMRI) allows assessing directions of interaction between brain regions. For real-time fMRI, we compared models of positive social emotion regulation based on a network involving the bilateral amygdala, dorsomedial prefrontal, and subgenual anterior cingulate cortex. The top-down regulation model implied modulation of the dorsomedial prefrontal cortex exerted onto other regions, while the bottom-up model implied the inverse modulation. The validity of model calculations was tested using the data from three healthy volunteers who imagined positive interactions with people in presented photos (stimuli). We confirmed the dominance of the top-down model and evaluated the number and duration of iterations required for model estimations. The study shows the applicability of the four-node effective connectivity models for regulation of positive social emotions using real-time fMRI, e.g., for neurofeedback applications., (© 2023. Springer Science+Business Media, LLC, part of Springer Nature.)

Real-time functional magnetic resonance imaging (rt-fMRI) neurofeedback was found to reduce depressive symptoms. However, no direct comparison of drug-free patients with an active psychotherapy control group is available. The present study compared rt-fMRI neurofeedback with cognitive behavioral therapy, as the standard treatment in patients declining anti-depressants. Twenty adult, drug-free patients with mild or moderate depression were non-randomly assigned either to a course of eight half-hour sessions of neurofeedback targeting the left medial prefrontal cortex (N = 12) or to a 16-session course of cognitive behavioral therapy (N = 8). Montgomery-Asberg Depression Rating Scale was introduced at baseline, mid-treatment, and end-treatment points. In each group, 8 patients each remained in the study to a mid-treatment evaluation and 6 patients each to the study end-point. ANOVA revealed a depression reduction with a significant effect of Time (F(3,6) = 19.0, p < 0.001, η 2  = 0.76). A trend to greater improvement in the cognitive behavioral therapy group compared to neurofeedback emerged (Group × Time; p = 0.078). Percent signal change in the region of interest between up- and down-regulation conditions was significantly correlated with session number (Pearson's r = 0.85, p < 0.001) indicating a learning effect. As limitations, small sample size could lead to insufficient power and non-random allocation to selection bias. Both neurofeedback and cognitive behavioral therapy improved mild and moderate depression. Neurofeedback was not superior to cognitive behavioral therapy. Noteworthy, the neurofeedback training course was associated with continuous improvement in the self-regulation skill, without plateau. This study delivers data to plan clinical trials comparing neurofeedback with cognitive behavioral interventions., (© 2022. The Author(s).)

Recently, human mesenchymal stem cells (hMSc) have attracted a great deal of attention as potential therapeutic agents in the treatment of socially significant diseases. Despite substantial advances in stem-cell therapy, the biological mechanisms of hMSc action after transplantation remain unclear. The use of magnetic resonance imaging (MRI) as a non-invasive method for tracking stem cells in the body is very important for analysing their distribution in tissues and organs, as well as for ensuring control of their lifetime after injection. Herein, detailed experimental data are reported on the biocompatibility towards hMSc of heavily gadolinium-doped cerium oxide nanoparticles (Ce 0.8 Gd 0.2 O 2-x ) synthesised using two synthetic protocols. The relaxivity of the nanoparticles was measured in a magnetic field range from 1 mT to 16.4 T. The relaxivity values ( r 1 = 11 ± 1.2 mM -1 s -1 and r 1 = 7 ± 1.2 mM -1 s -1 in magnetic fields typical of 1.5 and 3 T MRI scanners, respectively) are considerably higher than those of the commercial Omniscan MRI contrast agent. The low toxicity of gadolinium-doped ceria nanoparticles to hMSc enables their use as an effective theranostic tool with improved MRI-contrasting properties.

Frontal alpha asymmetry neurofeedback is used in affective disorders; however, little is known about the effects of this protocol on the composition of brain networks. In the current study, 13 healthy women underwent a course of self-regulation of the asymmetry of the EEG alpha or theta (control condition) band power. Before and after the course, resting state fMRI recordings were made. In the experimental group compared with the control group, the connectivity of the right occipital regions with the anterior cingulate, the left anterior insula, and the left caudate was blunted. Also, in the experimental group in the right hemisphere, the connectivity of the activity of the dorsal prefrontal cortex and the frontal pole was reduced. Thus, the experience of controlling the EEG alpha activity may specifically rearrange the functional connections of the emotional and motivational systems of the brain to the region of the maximum alpha amplitudes., (© 2022. Springer Science+Business Media, LLC, part of Springer Nature.)

We analyzed characteristics of diffusion and its kurtosis obtained using diffusion-kurtosis MRI in the hemisphere contralateral to the one affected by acute cerebrovascular accident. Diffusion characteristics in the white and gray matter were compared using analysis of covariance (ANCOVA) in healthy subjects and stroke patients with consideration for the age and sex factors. Significant differences between the groups were revealed for apparent diffusion coefficient and mean kurtosis in the white matter. Age dependence was studied using regression analysis and, according to the results of ANCOVA, this factor was found to be significant for apparent diffusion coefficient and diffusion kurtosis in the white matter. Metrics are proposed that can be used to determine the risk of stroke., (© 2022. Springer Science+Business Media, LLC, part of Springer Nature.)

This article discusses the contribution of fMRI- and fMRI-EEG-neurofeedback into recovery of motor function in two subacute stroke patients during the early post-stroke period. Premotor and supplementary motor zones of the cortex were chosen as the targets of voluntary control. Patient 1 received 6 sessions of motor imagery-based fMRI neurofeedback of secondary motor areas activity and Patient 2 received a similar course with the addition of μ- and β-EEG activity suppression. Both reduced the motor deficit severity, improved on the quality of life, and increased the C3/C4 coherence to other central leads within EEG μ-band. Patient 1 reliably increased the fMRI signal in target areas and improved on the strength and speed of hand movements. Patient 2 (fMRI-EEG) mastered the EEG activity regulation to a greater degree. The authors conclude that pure fMRI neurofeedback and bi-modal fMRI-EEG neurofeedback produce different clinical effects in motor rehabilitation, which confirms the prospect of the closed-loop stroke treatment., (© 2021. Springer Science+Business Media, LLC, part of Springer Nature.)

There are more than 30 inherited human disorders connected with repeat expansion (myotonic dystrophy type I, Huntington's disease, Fragile X syndrome). Fragile X syndrome is the most common reason for inherited intellectual disability in the human population. The ways of the expansion development remain unclear. An important feature of expanded repeats is the ability to form stable alternative DNA secondary structures. There are hypotheses about the nature of repeat instability. It is proposed that these DNA secondary structures can block various stages of DNA metabolism processes, such as replication, repair and recombination and it is considered as the source of repeat instability. However, none of the hypotheses is fully confirmed or is the only valid one. Here, an experimental system for studying (CGG)n repeat expansion associated with transcription and TCR-NER is proposed. It is noteworthy that the aberrations of transcription are a poorly studied mechanism of (CGG)n instability. However, the proposed systems take into account the contribution of other processes of DNA metabolism and, therefore, the developed systems are universal and applicable for various studies. Transgenic cell lines carrying a repeat of normal or premutant length under the control of an inducible promoter were established and a method for repeat instability quantification was developed. One type of the cell lines contains an exogenous repeat integrated into the genome by the Sleeping Beauty transposon; in another cell line, the vector is maintained as an episome due to the SV40 origin of replication. These experimental systems can serve for finding the causes of instability and the development of therapeutic agents. In addition, a criterion was developed for the quantification of exogenous (CGG)n repeat instability in the transgenic cell lines' genome., (Copyright © AUTHORS, 2021.)

Network mechanisms of depression development and especially of improvement from nonpharmacological treatment remain understudied. The current study is aimed at examining brain networks functional connectivity in depressed patients and its dynamics in nonpharmacological treatment. Resting state fMRI data of 21 healthy adults and 51 patients with mild or moderate depression were analyzed with spatial independent component analysis; then, correlations between time series of the components were calculated and compared between-group (study 1). Baseline and repeated-measure data of 14 treated (psychotherapy or fMRI neurofeedback) and 15 untreated depressed participants were similarly analyzed and correlated with changes in depression scores (study 2). Aside from diverse findings, studies 1 and 2 both revealed changes in within-default mode network (DMN) and DMN to executive control network (ECN) connections. Connectivity in one pair, initially lower in depression, decreased in no treatment group and was inversely correlated with Montgomery-Asberg depression score change in treatment group. Weak baseline connectivity in this pair also predicted improvement on Montgomery-Asberg scale in both treatment and no treatment groups. Coupling of another pair, initially stronger in depression, increased in therapy though was unrelated to improvement. The results demonstrate possible role of within-DMN and DMN-ECN functional connectivity in depression treatment and suggest that neural mechanisms of nonpharmacological treatment action may be unrelated to normalization of initially disrupted connectivity., Competing Interests: The authors declare that there is no conflict of interest regarding the publication of this paper., (Copyright © 2021 Dmitry D. Bezmaternykh et al.)

We performed a fMRI study during which 18 healthy subjects passively viewed abstract images and tried to name them. The images were geometric primitives, impossible images (Penrose images), and ambiguous images (Rorschach inkblots). Activation and deactivation areas were revealed for each task. The results of psychological assessment of ambiguity tolerance according to MSTAT-I inventory were used as regressors. Deactivation of the precuneus (Brodmann area 7) and neighboring structures (especially when observing geometric primitives and inventing names for them) and in the fronto-temporal areas was associated with high ambiguity tolerance. Similar links were observed for both activation and deactivation (depending on the certain contrast) of the occipito-cerebellar area.

We report a rare case of decompensated chronic internal hydrocephalus in an adult patient. A 35-year-old woman experienced acute intracranial hypertension in 3 weeks after relief of postoperative inflammation in the oral cavity (tooth extraction). MRI revealed severe internal hydrocephalus. Third ventriculostomy was followed by significant clinical improvement. However, postoperative survey and subsequent neuroimaging confirmed no reduction of ventricular system. Thus, decompensation of chronic hydrocephalus following dental intervention and subsequent oral inflammation was assumed. Impaired venous outflow from the brain and destabilization of CSF circulation can be considered as a pathogenetic mechanism.

Interaction of EEG and BOLD brain activity was studied in subjects during EEG-biofeedback training course (20 sessions). Healthy male subjects aged 20-35 underwent a training course of sound-reinforced upregulation of alpha- (20 participants) or beta-activity (9 participants). Pretraining, intermediate (after 10 sessions), and post-training fMRI-EEG recordings were conducted in resting state and during the participants' attempts to upregulate the power of target EEG activity. Regression analysis was carried out on three sessions in total; the main changes in BOLD signal connected with alpha rhythm power were related to the subjects who performed alpha training "good enough" (were able to increase alpha power at least at one stage). Maximum changes in BOLD response connected with alpha rhythm power were observed in the form of deactivation at T8 lead in the right hemisphere, and at F7 in the left hemisphere, and involved middle frontal gyrus, triangular part of inferior frontal gyrus, superior temporal gyrus, parietal lobule, and insula. The identified areas correspond to the executive control network (ECN) and anterior salience network (ASN).

Background: Apparent diffusion coefficient (ADC) is known as a quantitative biomarker of prenatal brain maturation. Fast macromolecular proton fraction (MPF) mapping is an emerging method for quantitative assessment of myelination that was recently adapted to fetal MRI., Purpose: To compare the capability of ADC and MPF to quantify the normal fetal brain development., Study Type: Prospective., Population: Forty-two human fetuses in utero (gestational age [GA] = 27.7 ± 6.0, range 20-38 weeks)., Field Strength/sequence: 1.5 T; diffusion-weighted single-shot echo-planar spin-echo with five b-values for ADC mapping; spoiled multishot echo-planar gradient-echo with T 1 , proton density, and magnetization transfer contrast weightings for single-point MPF mapping., Assessment: Two operators measured ADC and MPF in the medulla, pons, cerebellum, thalamus, and frontal, occipital, and temporal cerebral white matter (WM)., Statistical Tests: Mixed repeated-measures analysis of variance (ANOVA) with the factors of pregnancy trimester and brain structure; Pearson correlation coefficient (r); Hotelling-Williams test to compare strengths of correlations., Results: From the 2 nd to 3 rd trimester, ADC significantly decreased in the thalamus and cerebellum (P < 0.005). MPF significantly increased in the medulla, pons, thalamus, and cerebellum (P < 0.005). Cerebral WM had significantly higher ADC and lower MPF compared with the medulla and pons in both trimesters. MPF (r range 0.83, 0.89, P < 0.001) and ADC (r range -0.43, -0.75, P ≤ 0.004) significantly correlated with GA and each other (r range -0.32, -0.60, P ≤ 0.04) in the medulla, pons, thalamus, and cerebellum. No significant correlations or distinctions between regions and trimesters were observed for cerebral WM (P range 0.1-0.75). Correlations with GA were significantly stronger for MPF compared with ADC in the medulla, pons, and cerebellum (Hotelling-Williams test, P < 0.003) and similar in the thalamus. Structure-averaged MPF and ADC values strongly correlated (r = 0.95, P < 0.001)., Data Conclusion: MPF and ADC demonstrated qualitatively similar but quantitatively different spatiotemporal patterns. MPF appeared more sensitive to changes in the brain structures with prenatal onset of myelination., Level of Evidence: 2 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2019;50:52-61., (© 2019 International Society for Magnetic Resonance in Medicine.)

Synchronous fMRI-EEG mapping of cerebral activity in stroke patients made it possible to implement neurofeedback, a novel and promising therapeutic technology. This method integrates a real-time monitoring of cerebral activity by EEG and fMRI signals and training of the patients to control this activity simultaneously or alternatively via neurofeedback. The targets of such cerebral stimulation are cortical regions controlling arbitrary movements (Brodmann area 4), whereas its aim is optimization of activity in these regions in order to achieve better rehabilitation of stroke patients. The paper discusses the methodical details, advantages, and promise of bimodal neurofeedback treatment.

The connections between large neuronal networks were analyzed in 12 patients with ischemic or hemorrhagic strokes and hemiparesis included in the course of the interactive brain stimulation in the area of the primary motor cortex by the analysis of independent components of fMRI. The results obtained in 3 patients are presented. Desynchronization of the visual networks with each other and with the motor networks as well as positive dynamics in Rankin scale and box and blocks test were observed in the patients. These data attest to a decrease in the importance of visual control during movements and probably on partial restoration of prioperception. The important role of interactive brain stimulation and network analysis of fMRI data in neurology are discussed.

A course of interactive stimulation of primary motor cortex (Brodmann area 4) in the brain of a stroke patient resulted in recovery of locomotion volume in the paretic extremities and in improvement of general health accompanied with diverse changes in cerebral activity. During the training course, the magnitude of response in the visual fields of Brodmann areas 17 and 18 decreased; in parallel, the motor areas were supplemented with other ones such as area 24 (the ventral surface of anterior cingulate gyrus responsible for self-regulation of human brain activity and implicated into synthesis of tactile and special information) in company with Brodmann areas 40, 41, 43, 44, and 45. EEG data showed that neurofeedback sessions persistently increased the θ rhythm power in Brodmann areas 7, 39, 40, and 47, while the corresponding powers progressively decreased during a real motion. Both real motion and its virtual sibling constructed by interactive stimulation via neurofeedback were characterized with decreasing powers of the EEG β rhythm in Brodmann areas 6 and 8. The neurofeedback course decreased the coherence between the left Brodmann area 6 and some other ones examined in α and θ ranges. In the context of real motions, the coherence assessed in the EEG β range generally increased. Overall, the EEG and fMRI parameters attest to growing similarity between the moieties of functional communications effected in real and imaginary movements during neurofeedback course. The data open the vista for interactive stimulation to rehabilitate stroke patients; they highlight the important role of Brodmann areas in rearrangement of the brain in such patients; finally, the present results revealed the "common nervous pathway" that can be used to restore the capability for imaginary and real movements by a neurofeedback course after stroke.

Congenital medulloblastoma is extremely rare. MRI appearance of this tumor in the fetal brain has not been described. A case of congenital medulloblastoma initially observed by antenatal MRI with postnatal follow-up and treatment is presented. A pregnant female underwent fetal MRI on the 31st gestational week for routine indications. Midline cerebellar lesion of ≤2 cm in size with minor T 2 hypointensity and T 1 hyperintensity was identified. Additionally, quantitative MRI including apparent diffusion coefficient (ADC) and fast macromolecular proton fraction (MPF) mapping was performed. The lesion showed a marked ADC decrease and MPF increase. MPF maps depicted the lesion most conspicuously. After term delivery, a male neonate presented with symptoms of increased intracranial pressure. Postnatal MRI identified obstructive hydrocephalus caused by a large posterior fossa mass. The child was treated by cerebrospinal fluid shunt placement. Follow-up quantitative MRI on the fifth month revealed tumor growth and vivid changes of its tissue contrast associated with brain maturation. The tumor appeared nearly isointense on T 1 - and T 2 -weighted images and slightly hypointense on the ADC map. MPF contrast showed the most remarkable change from hyper- to hypointensity due to brain myelination with stable MPF in the tumor. Subsequently, the child underwent partial tumor resection, and currently continues treatment with chemotherapy. The pathological diagnosis was desmoplastic/nodular medulloblastoma. The described case illustrates evolution of the tumor contrast in the course of fetal and postnatal brain development and highlights the added diagnostic value of MPF mapping in fetal and neonatal neuroimaging., (Copyright © 2018. Published by Elsevier Inc.)

In depressed patients, changes in spontaneous brain activity, in particular, the strength of functional connectivity between different regions are observed. The data on changes in the synchrony of different regions of interest in the brain can serve as markers of depressive symptoms and as the targets for the corresponding therapy. The study involved 21 patients with mild depression and 21 healthy volunteers; by the time of second fMRI scanning, 15 and 19 subjects, respectively). The subjects underwent two 4-min sessions of resting state fMRI with 2-4 months interval between the recordings; on the basis of these data, functional connectivity between regions of interest was assessed. During the first session, depressed patients demonstrated more pronounced connection between the right frontal eye field and cerebellar area III. When the sample was restricted to subjects who underwent both fMRI sessions, depressed patients demonstrated closer relations of the right parietal operculum and cerebellar vermis area VIII. During the second recording, healthy subjects showed stronger connectivity between more than 20 frontal, temporal, and subcortical regions of interest and cerebellum area II. In healthy participants, brainstem functional interactions increased from the first to the second fMRI-recording. In depressed subjects a number of cortical areas split from left intraparietal sulcus, but the left temporal cortex became more intra-connected. The results confirm the differences in functional connectivity between depressed and healthy subjects. At the same time, attention should be paid to the variability of the data obtained.

fMRI markers of mild depression were revealed using standard emotional test. Patients with mild depression and healthy volunteers were asked to determine gender of subjects in photographs with different emotional expressions (neutral, surprise, disgust, confusion, anger, sadness, fear, and joy). The pattern of response to different emotions was universal in both groups and included the largest clusters in the occipital region, as well as a certain volume in the parietal lobes and posterior lateral frontal cortex. In depression group, a lack of activation in the middle cingulate gyrus (bilaterally) and in the postcentral and inferior parietal gyrus (left) in response to presentation of sad faces. For other emotion, no large clusters of intergroup contrasts significant at p<0.05 with FWE correction were revealed. The response of the middle cingulate gyrus and the left inferior parietal lobe can be considered as a potential diagnostic marker of depressive disorders and as the target for neurofeedback.

Depressive disorders can be associated with changes in not only interaction between neural networks, but also in their composition. Resting state fMRI scanning was performed for 4 min twice for each subject and the results of patients with mild depression (N=15) and healthy subjects (N=19) were analyzed. The fMRI signal was reduced into the independent components and the contrasts between the groups and between the first and second records were constructed for each component. During the first scanning, the auditory network of individuals with depression involved greater volume in the left insular region and lower volume in the right hemisphere. In record 2, depression patients were characterized by expansion of the executive network in the left hemisphere in the region of the middle and inferior frontal cortex. In healthy people, from record 1 to record 2, representation of the dorsal default mode network (DMN) increased in the left medial prefrontal area, the precuneus network expanded in the left hemisphere, and presentation of the ventral DMN in the right precuneus decreased. In the depression group, the auditory network lost some part of the left temporo-insular cortex; the sensorimotor network expanded in the left hemisphere to the cerebellum or to the central parietal region depending on the evaluation method, and the visuospatial network included or excluded a cluster in the left parietal lobe (in different points). Our findings indicate that connection of the auditory network with the left insular cortex could be a possible depression marker and also demonstrate a possibility of evaluating the composition of cerebral networks in intergroup comparisons and in dynamics without interventions.

Background and Purpose: Fast macromolecular proton fraction mapping is a recently emerged MRI method for quantitative myelin imaging. Our aim was to develop a clinically targeted technique for macromolecular proton fraction mapping of the fetal brain and test its capability to characterize normal prenatal myelination., Materials and Methods: This prospective study included 41 pregnant women (gestational age range, 18-38 weeks) without abnormal findings on fetal brain MR imaging performed for clinical indications. A fast fetal brain macromolecular proton fraction mapping protocol was implemented on a clinical 1.5T MR imaging scanner without software modifications and was performed after a clinical examination with an additional scan time of <5 minutes. 3D macromolecular proton fraction maps were reconstructed from magnetization transfer-weighted, T1-weighted, and proton density-weighted images by the single-point method. Mean macromolecular proton fraction in the brain stem, cerebellum, and thalamus and frontal, temporal, and occipital WM was compared between structures and pregnancy trimesters using analysis of variance. Gestational age dependence of the macromolecular proton fraction was assessed using the Pearson correlation coefficient ( r )., Results: The mean macromolecular proton fraction in the fetal brain structures varied between 2.3% and 4.3%, being 5-fold lower than macromolecular proton fraction in adult WM. The macromolecular proton fraction in the third trimester was higher compared with the second trimester in the brain stem, cerebellum, and thalamus. The highest macromolecular proton fraction was observed in the brain stem, followed by the thalamus, cerebellum, and cerebral WM. The macromolecular proton fraction in the brain stem, cerebellum, and thalamus strongly correlated with gestational age ( r = 0.88, 0.80, and 0.73; P < .001). No significant correlations were found for cerebral WM regions., Conclusions: Myelin is the main factor determining macromolecular proton fraction in brain tissues. Macromolecular proton fraction mapping is sensitive to the earliest stages of the fetal brain myelination and can be implemented in a clinical setting., (© 2018 by American Journal of Neuroradiology.)

Depression is associated with changes in the pattern of interaction of cerebral networks, which can reflect both existing symptoms and compensatory processes. The study is based on analysis of resting state fMRI data from 15 patients with mild depression and 19 conventionally healthy individuals. From fMRI signal recorded at rest for 4 min, the independent components were reconstructed. The intergroup differences and dynamics of functional connectivity from the first to the second recording were analyzed. Initially, depressive patients demonstrated weaker connectivity between cerebellar declive network (CN) and left central executive network (CEN) and also sensorimotor network (SMN); left CEN and primary visual network (PVN). During the second recording, the patients demonstrated more intensive reciprocal connection of the dorsal domain of default mode network (DMN) and auditory network (AN). In healthy subjects, positive correlations of the dorsal DMN and left CEN, right CEN and CN, and negative correlation of dorsal DMN and visuospatial network weakened from the first to second record. In the depression group, the interaction of AN with PVN, the right CEN with the anterior salience network and with ventral DMN weakened. At the same time, the connectivity between SMN and CN were strengthened. The results can be interpreted as spontaneous normalization of brain activity, but no direct evidence for their relation to the improvement of depression symptoms was found.

Neural networks interaction was studied in healthy men (20-35 years old) who underwent 20 sessions of EEG biofeedback training outside the MRI scanner, with concurrent fMRI-EEG scans at the beginning, middle, and end of the course. The study recruited 35 subjects for EEG biofeedback, but only 18 of them were considered as "successful" in self-regulation of target EEG bands during the whole course of training. Results of fMRI analysis during EEG biofeedback are reported only for these "successful" trainees. The experimental group (N = 23 total, N = 13 "successful") upregulated the power of alpha rhythm, while the control group (N = 12 total, N = 5 "successful") beta rhythm, with the protocol instructions being as for alpha training in both. The acquisition of the stable skills of alpha self-regulation was followed by the weakening of the irrelevant links between the cerebellum and visuospatial network (VSN), as well as between the VSN, the right executive control network (RECN), and the cuneus. It was also found formation of a stable complex based on the interaction of the precuneus, the cuneus, the VSN, and the high level visuospatial network (HVN), along with the strengthening of the interaction of the anterior salience network (ASN) with the precuneus. In the control group, beta enhancement training was accompanied by weakening of interaction between the precuneus and the default mode network, and a decrease in connectivity between the cuneus and the primary visual network (PVN). The differences between the alpha training group and the control group increased successively during training. Alpha training was characterized by a less pronounced interaction of the network formed by the PVN and the HVN, as well as by an increased interaction of the cerebellum with the precuneus and the RECN. The study demonstrated the differences in the structure and interaction of neural networks involved into alpha and beta generating systems forming and functioning, which should be taken into account during planning neurofeedback interventions. Possibility of using fMRI-guided biofeedback organized according to the described neural networks interaction may advance more accurate targeting specific symptoms during neurotherapy.

Patients with mild depression and apparently healthy individuals were presented images and asked to sort them into "pleasant" and "unpleasant" subsets. In both groups, the main differences between brain activation patterns during presentation of pleasant and unpleasant images were localized in the motor regions (precentral and postcentral gyrus) and in the cerebellum (p<0.05 with FWE correction). Most likely, these clusters are associated with motion (pressing a button in accordance with the instruction). According to the data of intergroup contrasts, patients with depression had less pronounced activation of frontal structures (middle frontal gyrus and other areas, including the white matter) in response to both positive and negative images (p<0.001). In healthy subjects, the response of the temporo-occipital areas (lingual and fusiform gyrus) to unpleasant stimuli was more intensive than in patients (p<0.001). This can be due to differences in the semantic image processing. Thus, in case of mild depression, the response of the amygdaloid complex, the key structure in the development in affective disorder, was not always observed. At the same time, the response of frontal and temporo-occipital regions has a certain potential as a biomarker of mild depression, although the reliability of the obtained data requires additional confirmation.

Some aspects of resting-state fMRI signal can be the key markers of depression. fMRI was recoded over 4 min in evidently healthy persons (N=21) and in patients with mild depression (N=21). The data were separated into the independent spatial components, and the strength of their association with established brain networks was analyzed. The patients with mild depression were characterized with greater correlations between the components representing the ventral and dorsal subdivisions of default mode network (DMN), whereas correlations between the components relating to cerebellum and to the left hemisphere language system were less pronounced. The data revealed a significant role of DMN in the development of affective abnormalities and importance of its functional state as a probable marker of mild depression.

In this report, we describe a molecular cytogenetic study of a family burdened with intellectual disability (ID) and suicide. Our study revealed that the mother has a heterozygous premutation in the FMR1 gene and supernumerary X chromosomes as well as X-derived marker chromosomes. Both of her sons have ID and a normal chromosome number. One of the sons has fragile X syndrome, and the other has ID of an unclear nature.

Brain EEG-fMRI activity was studied in subjects, who had successfully completed the EEG alpha stimulating training course (20 sessions): for 14 healthy men (20-35 years) three records were obtained in the feedback loop (biofeedback with EEG alpha rhythm with sound reinforcement): in the beginning, middle and at the end of the course. During alpha training, increased functional connectivity was revealed between precuneus network and anterior salience network, left executive control network, default mode network, primary visual network; anterior salience network and executive control network, visual-spatial network. The most prominent changes were found for precuneus network and anterior salience network, which could be due to their key role in the biofeedback phenomenon. Significant changes in functional connectivity were recorded for anterior salience network and precuneus network (synchronicity increased from the first to the third trial) and right and left executive control networks (weakening from the first to the second session.

The neurofeedback based on the motor areas fMRI signal may be a promising treatment for improving motor impairment in post-stroke conditions and Parkinson's disease. In the majority of the studies has been conducted using the 3 T MR machines, and the region of interest has been placed to the secondary motor areas. The current study attempted to perform an fMRI neurofeeback based on response of the right hand projection locus within primary motor cortex utilizing the 1.5 T MR scanner and using the optimal parameters for the named magnetic field strength. The subjects were 16 healthy participants who underwent a 30-minute imaging session comprised 1) individual func- tional localization of the region of interest (using the hand clinging task) and attempts to control its activity with 2) motor imagery and 3) any cognitive strategy chosen by participant. In both self-regulation conditions subjects activated G. precentralis, G. cinguli anterior, G. frontalis superior, G. parietalis inferior, and 6-th Brodman area. Activation maps for these two tasks didn't differ one from another significantly, and the involved area had only a few overlays with the region of interest map which signifies that training was unsucessful. The limitations of the study and factors influenc- ing the biofeedback efficacy negatively are discussed.

The review summarizes the data related to the potential of the real time fMRI biofeedback (the rt-fMRI), a novel technology implementing instructing patients to modify the neural activity in the certain brain regions related to the disordered function. The recent positive results were gained for a treatment of the post-stroke impairments, the Parkinson disease, the pain syndrome, the tinnitus, the alcohol and nicotine abuse, the major depression, and phobias of contamination and spiders. The intervention Was found to be less promising for schizophrenia and nearly ineffective for the criminal antisocial personality disorder. The reliability of the results is mostly poor due to suboptimal study designs, lack of the control groups, and insufficient sample sizes. The article deals with biological basis of the technology, its current applications and perspectives; and also its method- ologicdl and methodical problems.

fMRI-EEG dynamics of brain activity in volunteers was studied during the course of EEG alpha-stimulation training (20 sessions). Twenty-three healthy men (20-35 years) were subjected to 3-fold mapping in a feedback loop (EEG alpha-rhythm biofeedback with acoustic reinforcement). This procedure was performed at the beginning, middle, and end of the course. During the first neurofeedback training session, deactivation (p<0.001) was found in the right angular gyrus, supramarginal, and superior temporal gyri, Brodmann area 39, and cerebellum. Activation (p<0.001) was observed in the medial frontal and cingulate gyri, motor areas of both hemispheres, and Brodmann area 32. During final (third) neurofeedback training session, we observed strong deactivation (p<0.05 with FDR) of zones responsible for spatial thinking and motor functions: left medial frontal and left medial temporal gyri; right postcentral, lingual, and superior frontal gyri; insula and right side of the cerebellum; and precuneus and cuneus (Brodmann areas 6, 9, 7, 31, 8, 13, and 22). Changes in the alpha wave power were most pronounced in the primary and secondary somatosensory cortex of the left hemisphere (Brodmann areas 2L and 5L).

Comparative identification of cerebral regions activated in men and women during perception of indefinite images was carried out by fMRT and psychological testing. Nine men and nine women aged 20-26 years took part in the study. The volunteers examined simple geometric figures, slightly structurized images (tables from Rorschach's test), and images of impossible figures. Activation in the cerebellum and visual cortex (bilateral) was more pronounced in women in response to all types of images and less so in the right G. temporalis medius. The right frontal regions (G. precentralis, G. frontalis superior, G. frontalis medius) were also stronger activated in women in response to indefinite stimuli.

Using functional magnetic resonance imaging, we studied intracerebral dynamics during completion of Raven's Progressive Matrices test. Solving the test organized in sets of progressively increasing difficulty cause changes in cerebellar activation functionally related to cognitive activities and operations. As the tasks became more complicated, we observed gradual suppression of the activity of default mode network (DMN). The most pronounced changes in cerebral activation patterns occurred the second set of the test and involved associative somatosensory area and Wernicke's area that is known to play an important role in cognitive processes associated with synthesis and analysis of information.

For the first time in neurobiology-related issues, the synergistic spatial dynamics of EEG and fMRI (BOLD phenomenon) was studied during cognitive alpha biofeedback training in the operant conditioning mode (acoustic reinforcement of alpha-rhythm development and stability). Significant changes in alpha-rhythm intensity were found in T6 electrode area (Brodmann area 37). Brodmann areas related to solving alpha-training tasks and maximally involved in the formation of new neuronal network were middle and superior temporal gyri (areas 21, 22, and 37), fusiform gyrus, inferior frontal gyrus (areas 4, 6, and 46), anterior cingulate gyrus (areas 23 and 24), cuneus, and precuneus (area 7). Wide involvement of Brodmann areas is determined by psychological architecture of alpha-rhythm generating system control that includes complex cognitive activities: decision making, retrieval of long-term memory, evaluation of the reward and control efficiency during alpha-EEG biofeedback.

Functional magnetic resonance imaging (fMRI) of the brain was applied for preclinical evaluation of the efficiency of Divaza preparation intended for the treatment of cerebrovascular disorders. Psychological testing (Stroop task) in the magnetic field of fMRI was performed before and after 12-week treatment course using a double blind placebo-controlled protocol. It was shown that standard psychological and neuropsychological protocols do not allow fully estimate the results of treatment, whereas fMRI targeted the pool of cerebral structures activated during task solution. In the treatment group (in contrast to placebo), active zones in these structures were found only during task solution. Thus, resolution capability of fMRI significantly extends the range of rational screening by identifying active zones and can radically change the procedure of selection and clinical trials.

Inhalation of air-dispersed sub-micrometre and nano-sized particles presents a risk factor for animal and human health. Here, we show that nasal aerodynamics plays a pivotal role in the protection of the subterranean mole vole Ellobius talpinus from an increased exposure to nano-aerosols. Quantitative simulation of particle flow has shown that their deposition on the total surface of the nasal cavity is higher in the mole vole than in a terrestrial rodent Mus musculus (mouse), but lower on the olfactory epithelium. In agreement with simulation results, we found a reduced accumulation of manganese in olfactory bulbs of mole voles in comparison with mice after the inhalation of nano-sized MnCl2 aerosols. We ruled out the possibility that this reduction is owing to a lower transportation from epithelium to brain in the mole vole as intranasal instillations of MnCl2 solution and hydrated nanoparticles of manganese oxide MnO · (H2O)x revealed similar uptake rates for both species. Together, we conclude that nasal geometry contributes to the protection of brain and lung from accumulation of air-dispersed particles in mole voles., (© 2014 The Author(s) Published by the Royal Society. All rights reserved.)

Brain studies by magnetic resonance imaging, angiography, and spectroscopy have been performed with rat strains Wistar, GC (genetic and catatonia), and PM+ (pendulum movements). Both GC and PM+ rats show similar deviations from the ancestral Wistar population in having smaller areas of the right striatum (coronal slice). The anterior horns of lateral ventricles in GC rats are smaller than in the control strain. The maximum blood flow velocity in the common carotid arteries of PM+ rats is greater. The GC and PM+ strains differ in myo-inositol level in the hippocampus. The PM+ strain is characterized by a lower taurine level in the hippocampus, which may be one of the participants regulated the predisposition to audiogenic seizures.

We studied the intracerebral dynamics of developing skills for self-regulation of psychophysiological functions in the biofeedback game model via functional MRI. Multiple game plots managed by physiological characteristics leave a trace in the form of activity zones in the middle occipital gyrus, middle temporal gyrus, middle frontal gyrus, inferior parietal lobule, and declive functionally related to cognitive actions and operations. During the development of self-regulation skills, the gradual shift of the localization of areas of activity is observed towards sensory projection fields (e.g., thalamus, superior parietal lobule), which indicates distribution of the load toward the perceptual areas.

In subterranean rodents, which dig down the passages with frontal teeth, adaptation to the underground mode of life presumes forming of mechanisms that provide protection against inhaling dust particles of different size when digging. One of such mechanisms can be specific pattern of air flow organization in the nasal cavity. To test this assumption, comparative study of geometry and aerodynamics of nasal passages has been conducted with regard to typical representative of subterranean rodents, the mole vole, and a representative of ground rodents, the house mouse. Numerical modeling of air flows and deposition of micro- and nanoparticle aerosols indicates that sedimentation of model particles over the whole surface of nasal cavity is higher in mole vole than in house mouse. On the contrary, particles deposition on the surface of olfactory epithelium turns out to be substantially less in the burrowing rodent as compared to the ground one. Adaptive significance of the latter observation has been substantiated by experimental study on the uptake ofnanoparticles of hydrated manganese oxide MnO x (H2O)x and Mn ions from nasal cavity into brain. It has been shown with use of magnetic resonance tomography method that there is no difference between studied species with respect to intake of particles or ions by olfactory bulb when they are introduced intranasally. Meanwhile, when inhaling nanoparticle aerosol of MnCl2, deposition of Mn in mouse's olfactory bulbs surpasses markedly that in vole's bulbs. Thereby, the morphology of nasal passages as a factor determining the aerodynamics of upper respiratory tract ensures for burrowing rodents more efficient protection of both lungs and brain against inhaled aerosols than for ground ones.

In vivo proton magnetic resonance spectroscopy ((1) H MRS) of outbred stock ICR male mice (originating from the Institute of Cancer Research) was used to study the brain (hippocampus) metabolic response to the pro-inflammatory stimulus and to the acute deficiency of the available energy, which was confirmed by measuring the maximum oxygen consumption. Inhibition of glycolysis by means of an injection with 2-deoxy-d-glucose (2DG) reduced the levels of gamma-aminobutyric acid (GABA, p < 0.05, in comparison with control, least significant difference (LSD) test), N-acetylaspartate (NAA, p < 0.05, LSD test) and choline compounds, and at the same time increased the levels of glutamate and glutamine. An opposite effect was found after injection with bacterial lipopolysaccharide (LPS) - a very common pro-inflammatory inducer. An increase in the amounts of GABA, NAA and choline compounds in the brain occurred in mice treated with LPS. Different metabolic responses to the energy deficiency and the pro-inflammatory stimuli can explain the contradictory results of the brain (1) H MRS studies under neurodegenerative pathology, which is accompanied by both mitochondrial dysfunction and inflammation. The prevalence of the excitatory metabolites such as glutamate and glutamine in 2DG treated mice is in good agreement with excitation observed during temporary reduction of the available energy under acute hypoxia or starvation. In turn, LPS, as an inducer of the sickness behavior, which was manifested as depression, sleepiness, loss of appetite etc., shifts the brain metabolic pattern toward the prevalence of the inhibitory neurotransmitter GABA., (Copyright © 2014 John Wiley & Sons, Ltd.)

Functional MRI was applied for studying the dynamics of brain hemodynamic response evoked by involuntary (visual) and voluntary (motor) excitations under condition of interdependent sensorimotor and visual paradigm (hand clenching in response to a light flash). Activation of the corresponding areas of the visual and sensorimotor cortex (Brodmann areas 18-4, respectively) was observed and quantitative data characterizing the response signal maximum delay were obtained. It was found that breath holding-induced hypercapnia disorders neuronal networks created during visual-motor stimulation.

On-line brain mapping in subjects operating a competitive virtual gameplay was performed using functional magnetic resonance imaging. The interaction between the brain and visceral systems was studied on the model of real and simulated adaptive biofeedback. The immersion into a virtual story leads to a large-scale activation of cortical regions characterized by high values of voxels in the midtemporal, occipital, and frontal areas as well as in cingulate gyrus, cuneus, and precuneus (Brodmann areas 6, 7, 9, 10, 19, 24, 32, 39, 40, 45). The maximum increase in activity was observed during stage 2 of the game biofeedback, when the volumes of activated voxels increased several times in comparison with the starting phase. Qualitative characteristics of real and imitation game periods are discussed.

Using functional magnetic resonance imaging technique, we performed online brain mapping of gamers, practiced to voluntary (cognitively) control their heart rate, the parameter that operated a competitive virtual gameplay in the adaptive feedback loop. With the default start picture, the regions of interest during the formation of optimal cognitive strategy were as follows: Brodmann areas 19, 37, 39 and 40, i.e. cerebellar structures (vermis, amygdala, pyramids, clivus). "Localization" concept of the contribution of the cerebellum to cognitive processes is discussed.

In vivo proton magnetic resonance spectroscopy (1H MRS) of ICR male mice was used to study the brain (hippocampus) metabolic response to the acute deficiency of the available energy or to the pro-inflammatory stimulus. Inhibition of glycolysis by means of an intraperitoneal injection with 2-deoxy-D-glucose (2DG) reduced the levels of gamma-aminobutiric acid (GABA), N-acetylaspartate (NAA) and choline compounds, and at the same time increased the levels of glutamate and glutamine. An opposite effect was found after injection with bacterial lipopolysaccharide (LPS)--a very common pro-inflammatory inducer. An increase in the amounts of GABA, NAA and choline compounds in the brain occurred three hours after the injection of LPS. Different metabolic responses to the energy deficiency and the pro-inflammatory stimuli can explain the contradictory results of the brain MRS studies under neurodegenerative pathology, which is accompanied by both mitochondrial dysfunction and inflammation. Prevalence of the excitatory metabolites such as glutamate and glutamine in 2DG treated mice is in good agreement with excitation observed during temporary reduction of the available energy under acute hypoxia or starvation. In turn, LPS, as an inducer of the sickness behavior, shifts brain metabolic pattern to prevalence of the inhibitory neurotransmitter GABA.

This review describes functional magnetic resonance imaging (fMRI), the intravital noninvasive dynamic study of the active zones of cerebral structures at the time of their activity, fMR is based on the difference in magnetic properties of oxyhemoglobin--the oxygen carrier, and deoxyhemoglobin--a product produced in the areas of oxygen consumption, the brain parenchyma. This ratio is reflected as the physical phenomenon BOLD (blood oxygenation level dependent) that is a marker of neuronal activity. fMRI has good spatial resolution and the possibility of multiple repetitions of the research. This allows the 3D reconstruction of the sequence of formation and intracerebral "geometry" (stereometry) of newly formed neural ensembles (NE) and/or realization of potentially pre-existing NE. fMRI is an optimal tool for neuronal activity mapping, or more accurate, for functional state of the NE in the reconstruction of neural networks; it should be regarded as the technology for studying the brain of humans and animals, both in terms of natural life activity, and in pathological conditions.

The generating functions (GF) formalism was applied for calculation of spin density matrix evolution under the influence of periodic trains of RF pulses. It was shown that in a general case, closed expression for the generating function can be found that allows in many cases to derive analytical expressions for the generating function of spin density matrix (magnetization, coherences). This approach was shown to be particularly efficient for the analysis of multi-echo sequences, where one has to average over various frequency isochromats. The explicit analytical expressions for the generating function for echo amplitudes in a Carr-Purcell-Meiboom-Gill (CPMG) echo sequence, a multiecho sequence with incremental phase of refocusing pulse, a gradient echo sequence including transient period were obtained for an arbitrary flip angle and an arbitrary resonance offset. Comparison of the theory and the spin-echo experiments was done, demonstrating a good agreement.

Explicit non-recursive expressions for spin echo amplitudes have been derived for CPMG sequences with arbitrary refocusing flip angle.

Toxic and magnetic resonance contrast characteristics of new nitroxyl radicals Fur-135 and Fur-176 were studied in experiments on mice. The test compounds exhibited low toxicity and allowed us to increase contrasting of transplanted RLS lymphoma. Fur-135 differs by the type of contrasting from Gd(3+)-containing preparation omniscan and locates the tumor focus with high precision.

The paper provides the results of magnetic resonance tomographic examination of patients with acoustic neurinoma, and shows that the method can be used in the defining the site of a focus, its size, and relations of the tumor with adjacent tissues. The paper also outlines the image structure of the tumor in relation to scanning techniques and gives magnetic resonance criteria for differential diagnosis of tumor processes in the region of the cerebellopontine angle. It is concluded that magnetic resonance tomography is of high informative value in the diagnosis of extra-axial tumors of the posterior cranial fossa.

The authors discuss the results of a MR tomographic examination in 12 patients with ischemic apoplexy who underwent operation for the formation of an extra-intracranial microanastomosis. It is shown that MR tomography is a valuable diagnostic method which allows visualization of the ischemic foci. It is proved that in combination with CT it yields valuable information for determining the indications for revascularization of foci of ischemia in the brain.