Both groups participated in a five-visit motor imagery-based mental practice training program managed over a period of two months. The intervention group received mental practice training with real-time feedback of movement-associated cortical activity-beta band Hz event-related desynchronization ERD in electroencephalography EEGusing a novel custom-made brain-computer interface BCI system.
The control group received the mental practice training program without EEG cortical feedback. Motor excitability was assessed by measuring the frequency power magnitude of the EEG rhythmic activity associated with physical execution of wrist extension before and after the motor imagery-based mental practice training.
The EEG frequency power magnitude associated with the physical execution of wrist extension was significantly lower i. The mental practice training program with motor imagery-associated cortical feedback facilitated motor excitability during the production of voluntary motor control. Motor imagery-based mental practice training with movement-associated cortical activity feedback may provide an effective strategy to facilitate motor recovery in brain injury patients, particularly during the early rehabilitation stage when full participation in physical and occupational therapy programs may not be possible due to excessive motor weakness.
A survey on robotic devices for upper limb rehabilitation. The existing shortage of therapists and caregivers assisting physically disabled individuals at home isexpected to increase and become serious problem in the near future. The patient population needingphysical rehabilitation of the upper extremity is also constantly increasing. Robotic devices have thepotential to address this problem as noted by the results of recent research studies.
However, theavailability of these devices in clinical settings is limited, leaving plenty of room for improvement. The purpose of this paper is to document a review of robotic devices for upper limb rehabilitationincluding those in developing phase in order to provide a comprehensive reference about existingsolutions and facilitate the development of new and improved devices.
In particular the followingissues are discussed: This paper also includes a comprehensive, tabulated comparison oftechnical solutions implemented in various systems. Effects of robotic therapy of the arm after stroke. Three-dimensional, task-specific robot therapy of the arm after stroke: A multicentre, parallel-group randomised trial. Arm hemiparesis secondary to stroke is common and disabling.Transform Your Mind, Change Your Brain
We aimed to assess whether robotic training of an affected arm with ARMin-an exoskeleton robot that allows task-specific training in three dimensions-reduces motor impairment more effectively than does conventional therapy. In a prospective, multicentre, parallel-group randomised trial, we enrolled patients who had had motor impairment for more than 6 months and moderate-to-severe arm paresis after a cerebrovascular accident who met our eligibility criteria from four centres in Switzerland.
Eligible patients were randomly assigned 1: For both groups, therapy was given for at least 45 min three times a week for 8 weeks total 24 sessions. Assessors tested patients immediately before therapy, after 4 weeks of therapy, at the end of therapy, and 16 weeks and 34 weeks after start of therapy. Assessors were masked to treatment allocation, but patients, therapists, and data analysts were unmasked. Analyses were by modified intention to treat. This study is registered with ClinicalTrials.
Between May 4,and Sept 3,individuals were tested for eligibility, of whom 77 were eligible and agreed to participate. No serious adverse events related to the study occurred. Neurorehabilitation therapy including task-oriented training with an exoskeleton robot can enhance improvement of motor function in a chronically impaired paretic arm after stroke more effectively than conventional therapy. However, the absolute difference between effects of robotic and conventional therapy in our study was small and of weak significance, which leaves the clinical relevance in question.
A Pilot Study. A significant factor in impaired movement caused by stroke is the inability to activate muscles independently. Although the pathophysiology behind this abnormal coactivation is not clear, reducing the coactivation could improve overall arm function. A myoelectric computer interface MCIwhich maps electromyographic signals to cursor movement, could be used as a treatment to help retrain muscle activation patterns.
To investigate the use of MCI training to reduce abnormal muscle coactivation in chronic stroke survivors.
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A total of 5 healthy participants and 5 stroke survivors with hemiparesis participated in multiple sessions of MCI training. Participants performed isometric activations of up to 5 muscles. Activation of each muscle was mapped to different directions of cursor movement. The MCI specifically targeted 1 pair of muscles in each participant for reduction of coactivation. Both healthy participants and stroke survivors learned to reduce abnormal coactivation of the targeted muscles with MCI training.
Out of 5 stroke survivors, 3 exhibited objective reduction in arm impairment as well improvement in FMA-UE of 3 points in each of these patients. These results suggest that the MCI was an effective tool in directly retraining muscle activation patterns following stroke.
What You Think Matters. Oct J Neurosci. Imperceptible transcranial alternating current stimulation tACS changes the endogenous cortical oscillatory activity in a frequency-specific manner. In the human motor system, tACS coincident with the idling beta rhythm of the quiescent motor cortex increased the corticospinal output. We reasoned that changing the initial state of the brain i. We tested this hypothesis by delivering tACS at different frequencies theta, alpha, beta, and gamma on the primary motor cortex at rest and during motor imagery.
During motor imagery, the increase of corticospinal excitability was maximal with theta-tACS, likely reflecting a reinforcement of working memory processes required to mentally process and "execute" the cognitive task. As expected, the maximal MEPs increase with subjects at rest was instead obtained with beta-tACS, substantiating previous evidence. This dissociation provides new evidence of state and frequency dependency of tACS effects on the motor system and helps discern the functional role of different oscillatory frequencies of this brain region.
These findings may be relevant for rehabilitative neuromodulatory interventions. Neurofeedback training of motor imagery-related brain-states with brain-machine interfaces BMI is currently being explored prior to standard physiotherapy to improve the motor outcome of stroke rehabilitation.
Pilot studies suggest that such a priming intervention before physiotherapy might increase the responsiveness of the brain to the subsequent physiotherapy, thereby improving the clinical outcome. However, there is little evidence up to now that these BMI-based interventions have achieved operate conditioning of specific brain states that facilitate task-specific functional gains beyond the practice of primed physiotherapy.
In this context, we argue that BMI technology needs to aim at physiological features relevant for the targeted behavioral gain. Moreover, this therapeutic intervention has to be informed by concepts of reinforcement learning to develop its full potential.
Such a refined neurofeedback approach would need to address the following issues 1 Defining a physiological feedback target specific to the intended behavioral gain, e. This targeted brain state could well be different from the brain state optimal for the neurofeedback task 2 Selecting a BMI classification and thresholding approach on the basis of learning principles, i. Three upper limb robotic devices for stroke rehabilitation: A review and clinical perspective.
Stroke is a leading cause of disability worldwide. Many survivors of stroke remain with residual disabilities, even years later. Advances in technology have led to the development of a variety of robotic devices for use in rehabilitation. The integration of robotics in the delivery of neurorehabilitation is promising, but still not widely used in clinical settings. The aim of this review is to discuss the general design of three typical upper limb robotic devices, and examine the practical considerations for their use in a clinical environment.
Each device is described, the available clinical literature is reviewed and a clinical perspective is given on the usefulness of these robotic devices in rehabilitation of this population. Current literature supports the use of robotics in the clinical environment.
However, claims that robotic therapy is more effective than traditional treatment is not substantially supported. The majority of clinical trials reported are small, and lack the use of a control group for comparison treatment.
The use of robotics in stroke rehabilitation is still a relatively new treatment platform, and still evolving. As technological advances are made, there is much potential for growth in this field. A Controlled Study. Jul Ann Neurol. Chronic stroke patients with severe hand weakness respond poorly to rehabilitation efforts. Here, we evaluated efficacy of daily brain-machine interface BMI training to increase the hypothesized beneficial effects of physiotherapy alone in patients with severe paresis in a double-blind sham-controlled design proof of concept study.
Thirty-two chronic stroke patients with severe hand weakness were randomly assigned to 2 matched groups and participated in Both groups received identical behavioral physiotherapy immediately following BMI training or the control intervention. Upper limb motor function scores, electromyography from arm and hand muscles, placebo-expectancy effects, and functional magnetic resonance imaging fMRI blood oxygenation level-dependent activity were assessed before and after intervention.
Placebo-expectancy scores were comparable for both groups. The addition of BMI training to behaviorally oriented physiotherapy can be used to induce functional improvements in motor function in chronic stroke patients without residual finger movements and may open a new door in stroke neurorehabilitation. Dec Neural Plast. The corpus callosum, which is the largest white matter structure in the human brain, connects the 2 cerebral hemispheres. It plays a crucial role in maintaining the independent processing of the hemispheres and in integrating information between both hemispheres.
The functional integrity of interhemispheric interactions can be tested electrophysiologically in humans by using transcranial magnetic stimulation, electroencephalography, and functional magnetic resonance imaging. As a brain structural imaging, diffusion tensor imaging has revealed the microstructural connectivity underlying interhemispheric interactions. Sex, age, and motor training in addition to the size of the corpus callosum influence interhemispheric interactions.
Several neurological disorders change hemispheric asymmetry directly by impairing the corpus callosum. Moreover, stroke lesions and unilateral peripheral impairments such as amputation alter interhemispheric interactions indirectly. Noninvasive brain stimulation changes the interhemispheric interactions between both motor cortices.
Recently, these brain stimulation techniques were applied in the clinical rehabilitation of patients with stroke by ameliorating the deteriorated modulation of interhemispheric interactions. Here, we review the interhemispheric interactions and mechanisms underlying the pathogenesis of these interactions and propose rehabilitative approaches for appropriate cortical reorganization.
Interhemispheric Control of Unilateral Movement. To perform strictly unilateral movements, the brain relies on a large cortical and subcortical network. This network enables healthy adults to perform complex unimanual motor tasks without the activation of contralateral muscles. However, mirror movements involuntary movements in ipsilateral muscles that can accompany intended movement can be seen in healthy individuals if a task is complex or fatiguing, in childhood, and with increasing age.
Lateralization of movement depends on complex interhemispheric communication between cortical i. Brain computer interface BCI technology has been proposed for motor neurorehabilitation, motor replacement and assistive technologies. It is an open question whether proprioceptive feedback affects the regulation of brain oscillations and therefore BCI control. We developed a BCI coupled on-line with a robotic hand exoskeleton for flexing and extending the fingers.
Performance was defined as the difference in power of the sensorimotor rhythm during motor task and rest and calculated offline for different tasks. Participants were divided in three groups depending on the feedback receiving during task 2 the other tasks were the same for all participants. We observed that proprioceptive feedback feeling and seeing hand movements improved BCI performance significantly.
Furthermore, in the contingent positive group only a significant motor learning effect was observed enhancing SMR desynchronization during motor imagery without feedback in time. Furthermore, we observed a significantly stronger SMR desynchronization in the contingent positive group compared to the other groups during active and passive movements.
To summarize, we demonstrated that the use of contingent positive proprioceptive feedback BCI enhanced SMR desynchronization during motor tasks. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: Sep Exp Neurol. Neural synchrony within the motor system: What have we learned so far? Synchronization of neural activity is considered essential for information processing in the nervous system.
Both local and inter-regional synchronization are omnipresent in different frequency regimes and relate to a variety of behavioral and cognitive functions. Here, we review these studies with the purpose to delineate what they have added to our understanding of the neural control of movement. We highlight important findings regarding oscillations in primary motor cortex, synchronization between cortex and spinal cord, synchronization between cortical regions, as well as abnormal synchronization patterns in a selection of motor dysfunctions.
The interpretation of synchronization patterns benefits from combining results of invasive and non-invasive recordings, different data analysis tools, and modeling work.
Importantly, although synchronization is deemed to play a vital role, it is not the only mechanism for neural communication. Spike timing and rate coding act together during motor control and should therefore both be accounted for when interpreting movement-related activity.
Electromechanical and robot-assisted arm training for improving arm function and activities of daily living after stroke. Electromechanical and robot-assisted arm training devices are used in rehabilitation, and might help to improve arm function after stroke. To assess the effectiveness of electromechanical and robot-assisted arm training for improving generic activities of daily living, arm function, and arm muscle strength in patients after stroke.
We will also assess the acceptability and safety of the therapy. Search methods: We also handsearched relevant conference proceedings, searched trials and research registers, checked reference lists, and contacted trialists, experts and researchers in our field, as well as manufacturers of commercial devices.
Selection criteria: Randomised controlled trials RCTs comparing electromechanical and robot-assisted arm training for recovery of arm function with other rehabilitation or placebo interventions, or no treatment, for patients after stroke.
Data collection and analysis: Two review authors independently selected trials for inclusion, assessed trial quality, and extracted data. We included 19 trials involving participants in this update of our review. Electromechanical and robot-assisted arm training did improve activities of daily living SMD 0. Electromechanical and robot-assisted arm training did not increase the risk of patients to drop out RD 0. Patients who receive electromechanical and robot-assisted arm training after stroke are more likely to improve their generic activities of daily living.
Paretic arm function may also improve, but not arm muscle strength.
The_Limbic_System_and_Nearby_Structures_small | neuroscience | Brain anatomy, Limbic system, Brain
However, the results must be interpreted with caution because there were variations between the trials in the duration and amount of training, type of treatment, and in the patient characteristics. We show that exogenously induced frontoparietal theta synchronization significantly improves visual memory-matching reaction times as compared to placebo stimulation.
In contrast, exogenously induced frontoparietal theta desynchronization deteriorates performance. The present findings provide for the first time evidence of causality of theta phase-coupling of distant cortical areas for cognitive performance in healthy humans.
Moreover, the results demonstrate the suitability of transcranial alternating current stimulation to artificially induce coupling or decoupling of behaviorally relevant brain rhythms between segregated cortical regions. The common approach to the multiplicity problem calls for controlling the familywise error rate FWER. This approach, though, has faults, and we point out a few. A different approach to problems of multiple significance testing is presented.
It calls for controlling the expected proportion of falsely rejected hypotheses — the false discovery rate. This error rate is equivalent to the FWER when all hypotheses are true but is smaller otherwise.
Therefore, in problems where the control of the false discovery rate rather than that of the FWER is desired, there is potential for a gain in power. A simple sequential Bonferroni-type procedure is proved to control the false discovery rate for independent test statistics, and a simulation study shows that the gain in power is substantial. The use of the new procedure and the appropriateness of the criterion are illustrated with examples. The behavioral significance of coherent resting-state oscillations after stroke.
Mar NeuroImage. Parietofrontal integrity determines neural modulation associated with grasping imagery after stroke. Feb Brain. Chronic stroke patients with heterogeneous lesions, but no direct damage to the primary sensorimotor cortex, are capable of longitudinally acquiring the ability to modulate sensorimotor rhythms using grasping imagery of the affected hand.
Volitional modulation of neural activity can be used to drive grasping functions of the paralyzed hand through a brain-computer interface. The neural substrates underlying this skill are not known. Magnetoencephalography data acquired throughout training was used to derive functional networks. Structural network models and local estimates of extralesional white matter microstructure were constructed using T 1 -weighted and diffusion-weighted magnetic resonance imaging data.
We employed a graph theoretical approach to characterize emergent properties of distributed interactions between nodal brain regions of these networks. Patients displaying greater magnetoencephalography global cost-efficiency, a measure of information integration within the distributed functional network, achieved greater levels of skill.
Analysis of lesion damage to structural network connectivity revealed that the impact on nodal betweenness centrality of the ipsilesional primary motor cortex, a measure that characterizes the importance of a brain region for integrating visuomotor information between frontal and parietal cortical regions and related thalamic nuclei, correlated with skill.
Edge betweenness centrality, an analogous measure, which assesses the role of specific white matter fibre pathways in network integration, showed a similar relationship between skill and a portion of the ipsilesional superior longitudinal fascicle connecting premotor and posterior parietal visuomotor regions known to be crucially involved in normal grasping behaviour. Finally, estimated white matter microstructure integrity in regions of the contralesional superior longitudinal fascicle adjacent to primary sensorimotor and posterior parietal cortex, as well as grey matter volume co-localized to these specific regions, positively correlated with sensorimotor rhythm modulation leading to successful brain-computer interface control.
Thus, volitional modulation of ipsilesional neural activity leading to control of paralyzed hand grasping function through a brain-computer interface after longitudinal training relies on structural and functional connectivity in both ipsilesional and contralesional parietofrontal pathways involved in visuomotor information processing.
Extant integrity of this structural network may serve as a future predictor of response to longitudinal therapeutic interventions geared towards training sensorimotor rhythms in the lesioned brain, secondarily improving grasping function through brain-computer interface applications.
Gerwin Schalk. Many laboratories have begun to develop brain-computer interface BCI systems that provide communication and control capabilities to people with severe motor disabilities. Further progress and realization of practical applications depends on systematic evaluations and comparisons of different brain signals, recording methods, processing algorithms, output formats, and operating protocols.
However, the typical BCI system is designed specifically for one particular BCI method and is, therefore, not suited to the systematic studies that are essential for continued progress.
In response to this problem, we have developed a documented general-purpose BCI research and development platform called BCI BCI can incorporate alone or in combination any brain signals, signal processing methods, output devices, and operating protocols. This report is intended to describe to investigators, biomedical engineers, and computer scientists the concepts that the BCI system is based upon and gives examples of successful BCI implementations using this system.
To date, we have used BCI to create BCI systems for a variety of brain signals, processing methods, and applications. The data show that these systems function well in online operation and that BCI satisfies the stringent real-time requirements of BCI systems.
By substantially reducing labor and cost, BCI facilitates the implementation of different BCI systems and other psychophysiological experiments. It is available with full documentation and free of charge for research or educational purposes and is currently being used in a variety of studies by many research groups. EEG signal processing. Jan Comput Intell Neurosci. Electroencephalograms EEGs are becoming increasingly important measurements of brain activity and they have great potential for the diagnosis and treatment of mental and brain diseases and abnormalities.
With appropriate interpretation methods they are emerging as a key methodology to satisfy the increasing global demand for more affordable and effective clinical and healthcare services. Developing and understanding advanced signal processing techniques for the analysis of EEG signals is crucial in the area of biomedical research. This book focuses on these techniques, providing expansive coverage of algorithms and tools from the field of digital signal processing.
It discusses their applications to medical data, using graphs and topographic images to show simulation results that assess the efficacy of the methods. Additionally, expect to find: Brain-computer interface BCI technology has the prospects of helping stroke survivors by enabling the interaction with their environ ment through brain signals rather than through muscles, and restoring motor function by inducing activity-dependent brain plasticity.
This paper presents a clinical study on the extent of detectable brain signals from a large population of stroke patients in using EEG-based motor imagery BCI.
EEG data were collected from 54 stroke patients whereby finger tapping and motor imagery of the stroke-affected hand were performed by 8 and 46 patients, respectively.
EEG data from 11 patients who gave further consent to perform motor imagery were also collected for second calibration and third independent test sessions conducted on separate days.
Off-line accuracies of classifying the two classes of EEG from finger tapping or motor imagery of the stroke-affected hand versus the EEG from background rest were then assessed and compared to 16 healthy subjects. It does not mean, however, that volume conduction is irrelevant when true interactions are present. Here, we analyze in detail the possibilities to construct measures of true brain interactions which are strictly invariant to linear spatial transformations of the sensor data.
Specifically, such measures can be constructed from maximization of imaginary coherency in virtual channels, bivariate measures as a corrected variate of imaginary coherence, and global measures indicating the total interaction contained within a space or between two spaces.
A complete theoretic framework on this question is provided for second order statistical moments.
Towards a roadmap in brain protection and recovery
Relations to existing linear and nonlinear approaches are presented. We applied the methods to resting state EEG data, showing clear interactions at all bands, and to a combined measurement of EEG and MEG during rest condition and a finger tapping task. Statistical testing in electrophysiological studies. This article describes the mechanics and rationale of four different approaches to the statistical testing of electrophysiological data: These approaches are evaluated from the perspective of electrophysiological studies, which involve multivariate i.
Besides formal statistical techniques, there are also techniques that do not involve probability calculations but are very useful in dealing with multivariate data i. Moreover, data-based decision making can also be informed by mechanistic evidence that is provided by the structure in the data.
Nov J Neurosci. Motor learning changes the activity of cortical motor and subcortical areas of the brain, but does learning affect sensory systems as well? We examined in humans the effects of motor learning using fMRI measures of functional connectivity under resting conditions and found persistent changes in networks involving both motor and somatosensory areas of the brain.
We developed a technique that allows us to distinguish changes in functional connectivity that can be attributed to motor learning from those that are related to perceptual changes that occur in conjunction with learning. Using this technique, we identified a new network in motor learning involving second somatosensory cortex, ventral premotor cortex, and supplementary motor cortex whose activation is specifically related to perceptual changes that occur in conjunction with motor learning.
We also found changes in a network comprising cerebellar cortex, primary motor cortex, and dorsal premotor cortex that were linked to the motor aspects of learning. In each network, we observed highly reliable linear relationships between neuroplastic changes and behavioral measures of either motor learning or perceptual function. Motor learning thus results in functionally specific changes to distinct resting-state networks in the brain.
Assessment of cortical reorganisation for hand function after stroke. Nov J Physiol. Stroke often leads to impairment of hand function. Over the following months a variable amount of recovery can be seen.
The evidence from animal and human studies suggests that reorganization rather than repair is the key. Surviving neural networks are important for recovery of function and non-invasive techniques such as functional magnetic resonance imaging allow us to study them in humans. For example, initial attempts to move a paretic limb following stroke are associated with widespread activity within the distributed motor system in both cerebral hemispheres, more so in patients with greater impairment.
Disruption of activity in premotor areas using transcranial magnetic stimulation prior to movement can impair motor performance in stroke patients but not in controls suggesting that these new patterns of brain activity can support recovered function. In other words, this reorganisation is functionally relevant. More recently, research has been directed at understanding how surviving brain regions influence one another during movement. This opens the way for functional brain imaging to become a clinically useful tool in rehabilitation.
Understanding the dynamic process of systems level reorganization will allow greater understanding of the mechanisms of recovery and potentially improve our ability to deliver effective restorative therapy.
Effects of neurofeedback training with an electroencephalogram-based Brain Computer Interface for hand paralysis in patients with chronic stroke - a preliminary case series study. To explore the effectiveness of neurorehabilitative training using an electroencephalogram-based brain- computer interface for hand paralysis following stroke. A case series study. Eight outpatients with chronic stroke demonstrating moderate to severe hemiparesis.
Based on analysis of volitionally decreased amplitudes of sensory motor rhythm during motor imagery involving extending the affected fingers, real-time visual feedback was provided. After successful motor imagery, a mechanical orthosis partially extended the fingers. Brain-computer interface interventions were carried out once or twice a week for a period of months, and clinical and neurophysiological examinations pre- and post-intervention were compared.
New voluntary electromyographic activity was measured in the affected finger extensors in 4 cases who had little or no muscle activity before the training, and the other participants exhibited improvement in finger function. Significantly greater suppression of the sensory motor rhythm over both hemispheres was observed during motor imagery. Transcranial magnetic stimulation showed increased cortical excitability in the damaged hemisphere.
Success rates of brain-computer interface training tended to increase as the session progressed in 4 cases. Brain-computer interface training appears to have yielded some improvement in motor function and brain plasticity. Further controlled research is needed to clarify the role of the brain-computer interface system. Nonparametric statistical testing of coherence differences. Many important questions in neuroscience are about interactions between neurons or neuronal groups.
These interactions are often quantified by coherence, which is a frequency-indexed measure that quantifies the extent to which two signals exhibit a consistent phase relation. In this paper, we consider the statistical testing of the difference between coherence values observed in two experimental conditions. We pay special attention to problems induced by 1 unequal sample sizes and 2 the fact that coherence is typically evaluated at a large number of frequency bins and between large numbers of pairs of neurons or neuronal groups the multiple comparisons problem.
The original collection of chromosome-enumeration DNA probes to autosomes 1, 9, 15, 16, 18 and the sex chromosomes X and Y was used for the interphase cytogenetic analysis of chromosomes in the cells of the brain. Results and conclusion: The frequency of low-level aneuploidy per individual chromosome was 0. Thus, the three-fold increase in aneuploidy frequency in the brain in schizophrenia was detected.
It is suggested that mosaic aneuploidy, as a significant biological marker of genomic instability, may lead to genеtic imbalance and abnormal functional activity of neural cells and neural networks in schizophrenia. Hide publication data in Russian. Show publication data in Russian. Citations 4.
References 7. FISH was performed as described in a series of our previous molecular neuro cytogenetic reports   . The efficiency of IQ-FISH for scoring chromosomal loss was measured using our previous data on interphase molecular cytogenetic analysis of the same brain samples performed using interphase chromosome-specific multicolour banding or ICS-MCB for the whole datasets, see [24,25]. Chromosome losses were observed in 3.
Our studies of the normal and diseased human brain    have confirmed high applicability of QFISH in uncovering somatic chromosomal mosaicism in large cell populations. Interestingly, it has been reported that a QFISH protocol can be used for automated identification of gene amplifications . Full-text available. Feb Ivan Y Iourov Ilia V. Human Molecular Neurocytogenetics.
Sep Purpose of Review During the last decade, genomics has delivered basic insight into somatic genome variations contributing to human neuronal diversity in health and disease. Here, we review research on somatic chromosomal mosaicism and chromosome instability in the developing and adult normal and diseased human brain, representing the emerging field of molecular neurocytogenetics.
Recent Findings Chromosome instability and somatic chromosomal mosaicism were found to be involved in human brain development. Additionally, recent studies have highlighted the impact of neuronal aneuploidy and brain-specific chromosome instability on normal and pathological neurodevelopment and brain aging.
Summary Neurocytogenomic variations are nowadays thought to play a critical role in human brain development and aging. Chromosome instability is likely to be an element of pathogenetic cascades in a variety of brain diseases. Finally, human molecular neurocytogenetics may be recognized as an integral component of current biomedical science. Yuri B. Yurov Dec Ivan Y Iourov. Mosaic Brain Aneuploidy in Mental Illnesses: Postzygotic chromosomal variation in neuronal cells is hypothesized to make a substantial contribution to the etiology and pathogenesis of neuropsychiatric disorders.
However, the role of somatic genome instability and mosaic genome variations in common mental illnesses is a matter of conjecture. The greatest increase in SCP was detected in the frontal part of the brain which causes the violation of the functional systems providing arbitrary regulation. Children with ADHD demonstrated a marked violation of the principle of spherical distribution of energy consumption: There was a significant correlation between neurometabolism of the cerebral cortex and the activation level, due to the violation of the functional activity of nonspecific reticulo-limbic-cortical neural connections.
The authors conclude that the state of the activating mechanisms and neurometabolic reactions are important factors affecting the formation mechanisms of ADHD. Citations 0. References Dopamine receptor DRD4 gene and stressful life events in persistent attention deficit hyperactivity disorder. We subsequently investigated the interaction of stressful life events with these two DRD4 polymorphisms, and the impact of such events on the severity of ADHD symptomatology.
The gene-by-environment analysis revealed an independent effect of stressful experiences on the severity of persistent ADHD, and a gene-by-environment interaction on the inattentive dimension of the disorder, where non carriers of the Dup bp L - VNTR 48bp 7R haplotype were more sensitive to environmental adversity than carriers. These results are in agreement with previous works reporting a relationship between DRD4 and the effect of adverse experiences, which may explain the discordant findings in previous genetic studies and strengthen the importance of gene-by-environment interactions on the severity of ADHD.
Modeling ADHD: A review of ADHD theories through their predictions for decision-making and reinforcement learning. Ziegnler S. Психофизиология функциональных состояний и познавательной деятельности здорового и больного человека: Институт мозга человека РАН, В А Илюхина. Илюхина В. Нехорошкова А. Панков М. Jan А Н Подоплекин. Подоплекин А. Энергетическая физиология мозга: Фокин В. Антидор, Feasibility of a short-tern setting and plasticity effects.
Doren J. International Journal of Psychophysiology,vol. A Systematic Review and Metaregression Analysis. Polanczyk G. Psychiatry,vol. Brain imaging genetics in ADHD and beyond — Mapping pathways from gene to disorder at different levels of complexity.
Full-text available. Beyond gene-finding, neurobiological parameters, such as brain structure, connectivity, and function, have been used to link genetic variation to ADHD symptomatology. Fifty-one eligible research articles described studies of 13 ADHD candidate genes. Almost exclusively, single genetic variants were studied, mostly focussing on dopamine-related genes. While promising results have been reported, imaging genetics studies are thus far hampered by methodological differences in study design and analysis methodology, as well as limited sample sizes.
Beyond reviewing imaging genetics studies, we also discuss the need for complementary approaches at multiple levels of biological complexity and emphasize the importance of combining and integrating findings across levels for a better understanding of biological pathways from gene to disease. These may include multi-modal imaging genetics studies, bioinformatic analyses, and functional analyses of cell and animal models. Natalie Colaneri. Background Recent studies report that a significant number of adolescents misuse and divert prescription stimulants.
As prescribers of these medications, physicians have a unique opportunity to help prevent the improper use and unlawful distribution of these medications. This study evaluates the extent to which physicians employ prevention practices with their adolescent patients with ADHD and their perceptions of the effectiveness of these practices.
Methods A questionnaire was developed and mailed to child and adolescent psychiatrists, child neurologists, and developmental-behavioral pediatricians in the US. Conversely, Many responding physicians do not regularly implement practices that may prevent stimulant misuse, and the majority thinks most prevention practices are not very effective.
Conclusion Physicians should assume greater responsibility in the prevention of stimulant misuse and diversion by implementing prevention practices more often with their adolescent patients with ADHD.
With respect to the generalizability of these findings, it must be noted that the sample was limited to pediatric subspecialists and may be influenced by selection bias and response bias. A meta-analysis. Jun Two investigators selected related studies and assessed methodological quality independently. Six studies were included in this meta-analysis for a total of cases and controls.
There is no apparent association between rs polymorphisms and risk of ADHD. However, subgroup analysis based on ethnicity demonstrated a strong association between rs polymorphism and ADHD in the subset of Asian participants, but not among Caucasians. Our result suggests that the polymorphisms rs and rs may increase the odds of developing ADHD.
Additional studies are needed to confirm these findings. The aim of this study was to examine local and global brain volume differences between typically developing children TD and children with a diagnosis of ADHD.
Using an ROI approach caudate volume differences were also examined. Structural magnetic resonance imaging data were analysed using voxel-based morphometry.
The ADHD group had significantly lower global and local grey matter volumes within clusters in the bilateral frontal, right parietal and right temporal regions compared to TD.
A significant group by age interaction was found for right caudate nucleus volume. Feb Behav Genet. This review focuses on how measured pre- and perinatal environmental and epi genetic risk factors are interrelated and potentially influence one, of many, common developmental pathway towards ADHD. Prenatal ischemia-hypoxia insufficient blood and oxygen supply in utero is a primary pathway to lower birth weight and produces neurodevelopmental risk for ADHD.
To promote tissue survival in the context of ischemia-hypoxia, ischemia-hypoxia response IHR pathway gene expression is altered in the developing brain and peripheral tissues.
Taken together, IHR genetic vulnerability to ischemia-hypoxia and IHR epigenetic alterations following prenatal ischemia-hypoxia may result in neurodevelopmental vulnerability for ADHD.