scholarly journals Spatially bivariate EEG-neurofeedback can manipulate interhemispheric rebalancing of M1 excitability

2021 ◽  
Author(s):  
Masaaki Hayashi ◽  
Kohei Okuyama ◽  
Nobuaki Mizuguchi ◽  
Ryotaro Hirose ◽  
Taisuke Okamoto ◽  
...  
Keyword(s):  
Dynamic Range ◽  
Theoretical Concept ◽  
Interhemispheric Inhibition ◽  
Interhemispheric Connectivity ◽  
Sensorimotor Activity ◽  
Eeg Neurofeedback ◽  
Stimulation Paradigm ◽  
The Brain ◽  
Sensorimotor Processes ◽  
Recovery Of Motor Function

Human behavior requires interregional crosstalk to employ the sensorimotor processes in the brain. Although some external neuromodulation tools have been used to manipulate interhemispheric sensorimotor activity, a central controversy concerns whether this activity can be volitionally controlled. Experimental tools lack the power to up- or down-regulate the state of the targeted hemisphere over a large dynamic range and, therefore, cannot evaluate the possible volitional control of the activity. We overcame this difficulty by using the recently developed method of spatially bivariate electroencephalography (EEG)-neurofeedback to systematically enable participants to manipulate their bilateral sensorimotor activities. Herein, we report that bi-directional changes in ipsilateral excitability to the imagined hand (conditioning hemisphere) affect interhemispheric inhibition (IHI) assessed by paired-pulse transcranial magnetic stimulation paradigm. In addition, participants were able to robustly manipulate the IHI magnitudes. Further physiological analyses revealed that the self-manipulation of IHI magnitude reflected interhemispheric connectivity in EEG and TMS, which was accompanied by intrinsic bilateral cortical oscillatory activities. Our results provide clear neuroscientific evidence regarding the inhibitory interhemispheric sensorimotor activity and IHI manipulator, thereby challenging the current theoretical concept of recovery of motor function for neurorehabilitation.

scholarly journals Homeostatic plasticity mechanisms in mouse V1

2017 ◽  
Vol 372 (1715) ◽  
pp. 20160504 ◽  
Author(s):  
Megumi Kaneko ◽  
Michael P. Stryker
Keyword(s):  
Visual Cortex ◽  
Primary Visual Cortex ◽  
Neuronal Activity ◽  
Dynamic Range ◽  
Ocular Dominance ◽  
Homeostatic Plasticity ◽  
Ocular Dominance Plasticity ◽  
The Brain

Mechanisms thought of as homeostatic must exist to maintain neuronal activity in the brain within the dynamic range in which neurons can signal. Several distinct mechanisms have been demonstrated experimentally. Three mechanisms that act to restore levels of activity in the primary visual cortex of mice after occlusion and restoration of vision in one eye, which give rise to the phenomenon of ocular dominance plasticity, are discussed. The existence of different mechanisms raises the issue of how these mechanisms operate together to converge on the same set points of activity. This article is part of the themed issue ‘Integrating Hebbian and homeostatic plasticity’.

scholarly journals GPCR-Based Dopamine Sensors—A Detailed Guide to Inform Sensor Choice for In Vivo Imaging

2020 ◽  
Vol 21 (21) ◽  
pp. 8048
Author(s):  
Marie A. Labouesse ◽  
Reto B. Cola ◽  
Tommaso Patriarchi
Keyword(s):  
In Vivo Imaging ◽  
Dynamic Range ◽  
New Techniques ◽  
Experimental Parameters ◽  
Sensor Properties ◽  
Molecular Specificity ◽  
Freely Behaving ◽  
The Brain ◽  
Da Release

Understanding how dopamine (DA) encodes behavior depends on technologies that can reliably monitor DA release in freely-behaving animals. Recently, red and green genetically encoded sensors for DA (dLight, GRAB-DA) were developed and now provide the ability to track release dynamics at a subsecond resolution, with submicromolar affinity and high molecular specificity. Combined with rapid developments in in vivo imaging, these sensors have the potential to transform the field of DA sensing and DA-based drug discovery. When implementing these tools in the laboratory, it is important to consider there is not a ‘one-size-fits-all’ sensor. Sensor properties, most importantly their affinity and dynamic range, must be carefully chosen to match local DA levels. Molecular specificity, sensor kinetics, spectral properties, brightness, sensor scaffold and pharmacology can further influence sensor choice depending on the experimental question. In this review, we use DA as an example; we briefly summarize old and new techniques to monitor DA release, including DA biosensors. We then outline a map of DA heterogeneity across the brain and provide a guide for optimal sensor choice and implementation based on local DA levels and other experimental parameters. Altogether this review should act as a tool to guide DA sensor choice for end-users.

scholarly journals A Noninvasive Positron Computed Tomography Technique Using Oxygen-15-Labeled Water for the Evaluation of Neurobehavioral Task Batteries

1985 ◽  
Vol 5 (1) ◽  
pp. 70-78 ◽  
Author(s):  
John C. Mazziotta ◽  
Sung-Cheng Huang ◽  
Michael E. Phelps ◽  
Richard E. Carson ◽  
Norman S. MacDonald ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Visual Stimulation ◽  
Normal Subjects ◽  
Normal Volunteers ◽  
Concentration Changes ◽  
Flow Changes ◽  
Water Simulation ◽  
Stimulation Paradigm ◽  
The Brain ◽  
Good Agreement

A technique is described that provides information about relative cerebral responses to differing neurobehavioral tasks in normal subjects studied with positron computed tomography and oxygen-15-labeled water. Simulation studies demonstrate that this technique is sensitive to changes in true local CBF within a physiological range and tends to underestimate relative flow changes at high flow values (>30 ml min−1 100 g−1) and to overestimate these changes for flow values of <25 ml min−1 100 g−1. Image acquisition times of 60 s following the arrival of oxygen-15-labeled water in the brain were the most accurate for identifying such relative changes between radioisotope administrations and were not limited by statistical noise from total image counts. Studies in normal volunteers indicate that the technique is highly reproducible, demonstrating a coefficient of variation for small (<2 cm2) regions of 2.98 between studies in the same state. Visual stimulation studies in normal volunteers demonstrated relative radioisotope concentration changes between control and stimulated states that are in good agreement with similar results obtained using the same stimulation paradigm but with the use of fluorodeoxyglucose to determine cerebral glucose metabolism.

scholarly journals Functional advantages of Lévy walks emerging near a critical point

2020 ◽  
Vol 117 (39) ◽  
pp. 24336-24344 ◽  
Author(s):  
Masato S. Abe
Keyword(s):  
Critical Point ◽  
Dynamic Range ◽  
Movement Trajectories ◽  
Lévy Walks ◽  
Optimal Dynamic ◽  
Freely Moving ◽  
High Flexibility ◽  
Open Question ◽  
The Brain ◽  
Power Law Distributions

A special class of random walks, so-called Lévy walks, has been observed in a variety of organisms ranging from cells, insects, fishes, and birds to mammals, including humans. Although their prevalence is considered to be a consequence of natural selection for higher search efficiency, some findings suggest that Lévy walks might also be epiphenomena that arise from interactions with the environment. Therefore, why they are common in biological movements remains an open question. Based on some evidence that Lévy walks are spontaneously generated in the brain and the fact that power-law distributions in Lévy walks can emerge at a critical point, we hypothesized that the advantages of Lévy walks might be enhanced by criticality. However, the functional advantages of Lévy walks are poorly understood. Here, we modeled nonlinear systems for the generation of locomotion and showed that Lévy walks emerging near a critical point had optimal dynamic ranges for coding information. This discovery suggested that Lévy walks could change movement trajectories based on the magnitude of environmental stimuli. We then showed that the high flexibility of Lévy walks enabled switching exploitation/exploration based on the nature of external cues. Finally, we analyzed the movement trajectories of freely moving Drosophila larvae and showed empirically that the Lévy walks may emerge near a critical point and have large dynamic range and high flexibility. Our results suggest that the commonly observed Lévy walks emerge near a critical point and could be explained on the basis of these functional advantages.

Effects of Graft Placement Site on the Survival of Adrenal Medulla Transplants into the Brain and Its Relation with the Recovery of Motor Function

2000 ◽  
Vol 31 (6) ◽  
pp. 551-557 ◽  
Author(s):  
Verónica Anaya-Martı́nez ◽  
Enrique Montiel-Flores ◽  
Jesús Espinosa-Villanueva ◽  
Fernando Garcı́a-Hernández
Keyword(s):  
Motor Function ◽  
Adrenal Medulla ◽  
Graft Placement ◽  
The Brain ◽  
Recovery Of Motor Function

Studying semantics in the brain: the rapid stream stimulation paradigm

2001 ◽  
Vol 8 (3) ◽  
pp. 199-207 ◽  
Author(s):  
José A Hinojosa ◽  
Manuel Martı́n-Loeches ◽  
Pilar Casado ◽  
Francisco Muñoz ◽  
Carlos Fernández-Frı́as ◽  
...  
Keyword(s):  
Stimulation Paradigm ◽  
The Brain

scholarly journals Experimental Model for Studying the Prefrontal EEG Biomarkers in Correlation with Food Intake Behavior: Neurofeedback Platform

2021 ◽  
Author(s):  
Mohammed Isam Al-Hiyali ◽  
Asnor Juraiza Ishak ◽  
Hafiz Harun ◽  
Siti Anom Ahmad ◽  
Wan Aliaa Sulaiman
Keyword(s):  
Prefrontal Cortex ◽  
Food Intake ◽  
Therapeutic Potential ◽  
Brain Activity ◽  
Self Report ◽  
Significant Decrement ◽  
Positive Treatment ◽  
Eeg Neurofeedback ◽  
The Impact ◽  
The Brain

Background: This study aims to investigate the effects of visual neurofeedback stimulation on the brain activity in overweight cases. The neuroscience studies indicated the personal decision about eating under the impact of environmental factors such as (visually, smelling, tasting) is related to neural activity of the prefrontal lobe of the brain. Therefore, there were many attempts to modify the food intake behavior in overweight cases through the stimulation of the prefrontal cortex. However, the empirical viewing of EEG-neurofeedback experiments has not explicated the details about the effect of the EEG-NF, the specificity of positive treatment effects remains in a challenging scope.Methods: This study is a cue-exposure EEG-NF experiment to verify the hypothesis of effecting the EEG-NF on the electrical activity of PFC and modifying the general symptoms of food intake behavior in overweight cases. Twenty-four individuals were recruited as participants for this study. These participants were assigned randomly into two groups; the EX-Group (N=12) enrolled in 8 sessions of the EEG-NF experiment, and the C-Group (N=12) was listed in no EEG-NF sessions. The participants provided researchers with a self-report questionnaire relating to their observation of general symptoms of food intake behavior, and EEG signals recordings into the pre and posts stimulation phase. The power spectral density (PSD) method was applied for EEG parameters extraction.Results: The results of a two-way analysis of variance (ANOVA) explained that a significant variation in variables between the two groups after the EEG-NF experiment. The analysis of the quantitative variables indicated that the effect of EEG-NF experiment was a significant decrement in EEG power bands which significantly influenced changing the median of self-report questionnaire responses that is related to general symptoms of food intake behavior.Conclusions: This study provides preliminary support for the therapeutic potential of EEG-NF experiment that targets the prefrontal cortex, to influence neural processes underlying food intake behavior in overweight cases.

scholarly journals Shocking the brain to regain motor function : a non-invasive therapy for stroke patients

2018 ◽  
Vol 1 ◽  
pp. 20-22
Author(s):  
Michael Min Wah Leung
Keyword(s):  
Direct Current ◽  
Transcranial Direct Current Stimulation ◽  
Invasive Technique ◽  
Stroke Patients ◽  
Interhemispheric Inhibition ◽  
Brain Areas ◽  
Sensory Deficits ◽  
Direct Current Stimulation ◽  
Non Invasive ◽  
The Brain

Invasive treatments and its associated risks are important factors of concern when the conditions are affecting the nervous system. Transcranial direct current stimulation (tDCS) is a non-invasive technique that stimulates brain areas through the scalp and has excitatory or inhibitory neuromodulatory effects. In the context of stroke patients, recovery is often impaired from the increased inhibition of the damaged area from the unaffected hemisphere. Fujimoto et al. uses dual-hemisphere transcranial direct current stimulation to address this interhemispheric inhibition and demonstrates that stroke patients were able to periodically restore sensory deficits. 

16 Noninvasive deep brain stimulation via delivery of temporally interfering electric fields

2020 ◽  
Vol 91 (8) ◽  
pp. e6.3-e7
Author(s):  
Nir Grossman
Keyword(s):  
Electric Field ◽  
Electric Fields ◽  
Brain Stimulation ◽  
Dynamic Range ◽  
Imperial College ◽  
Network Activity ◽  
Massachusetts Institute Of Technology ◽  
Neural Firing ◽  
Institute Of Technology ◽  
The Brain

Nir is a Lecturer (Assistant Professor) at Imperial College London and a founding fellow of the UK Dementia Research Institute (UK-DRI). The long-term goal of his research is to develop neuromodulatory interventions for neurodegenerative diseases by direct modulation of the underlying aberrant network activity. Nir received a BSc in Physics from the Israeli Institute of Technology (Technion), an MSc in Electromagnetic Engineering from the Technical University of Hamburg-Harburg, and a PhD in Neuroscience from Imperial College London. He then completed a postdoc training, as a Wellcome Trust Fellow, at the Massachusetts Institute of Technology (MIT) and Harvard University. Nir was recently awarded the prestige prize for Neuromodulation from the Science magazine for describing how temporal interfering of kHz electric fields can non-invasively stimulate focal neural structures deep in the brain.Electrical brain stimulation is a key technique in research and clinical neuroscience studies, and also is in increasingly widespread use from a therapeutic standpoint. However, to date all methods of electrical stimulation of the brain either require surgery to implant an electrode at a defined site, or involve the application of non-focal electric fields to large fractions of the brain. We report a noninvasive strategy for electrically stimulating neurons at depth. By delivering to the brain multiple electric fields at frequencies too high to recruit neural firing, but which differ by a frequency within the dynamic range of neural firing, we can electrically stimulate neurons throughout a region where interference between the multiple fields results in a prominent electric field envelope modulated at the difference frequency. We validated this temporal interference (TI) concept via modeling and physics experiments, and verified that neurons in the living mouse brain could follow the electric field envelope. We demonstrate the utility of TI stimulation by stimulating neurons in the hippocampus of living mice without recruiting neurons of the overlying cortex. Finally, we show that by altering the currents delivered to a set of immobile electrodes, we can steerably evoke different motor patterns in living mice.

Sign in / Sign up

Export Citation Format

Share Document