scholarly journals Negative covariation between task-related responses in alpha/beta-band activity and BOLD in human sensorimotor cortex: An EEG and fMRI study of motor imagery and movements

NeuroImage ◽  
2010 ◽  
Vol 49 (3) ◽  
pp. 2596-2606 ◽  
Author(s):  
Han Yuan ◽  
Tao Liu ◽  
Rebecca Szarkowski ◽  
Cristina Rios ◽  
James Ashe ◽  
...  
Keyword(s):  
Motor Imagery ◽  
Sensorimotor Cortex ◽  
Beta Band ◽  
Fmri Study ◽  
Alpha Beta ◽  
Band Activity

scholarly journals SENSORIMOTOR POTENTIATION OF MOTOR IMAGINATION AS CNS PLASTICITY ACTIVATOR

2016 ◽  
Vol 1 (3) ◽  
pp. 33-38
Author(s):  
E S Korovina ◽  
E N Glazkova ◽  
I V Shirolapov ◽  
O G Kuznetsova ◽  
N R Khanbikov ◽  
...  
Keyword(s):  
Left Hemisphere ◽  
Motor Imagery ◽  
Sensorimotor Cortex ◽  
Motor Pattern ◽  
Elbow Flexion ◽  
Recording System ◽  
Eeg Rhythms ◽  
Before And After ◽  
Alpha Beta ◽  
The Right

Aim - to find out the neurophysiological correlatives of motor imagery after the simulation of the motor pattern. Materials and methods. Monopolar EEG was recorded using EEG recording system Neuron - Spectrum - 4 / VPM at 7 right-handed volunteers aged 18-19 years. EEG was recorded according to the system 10-5 in the projection of the sensorimotor cortex of the left hemisphere during the imagination of two movements in the right hand (flexing the fingers, elbow flexion) before and after 30 seconds of simulation of movement patterns using the rehabilitation device Power Plate. Results. After the simulation of the motor pattern, the imagination of the two types of movement correlated with desynchronization of alpha-, beta- EEG rhythms, increasing the number of leads with the reaction of desynchronization (p

scholarly journals Reduction of spontaneous cortical beta bursts in Parkinson’s disease is linked to symptom severity

2020 ◽  
Vol 2 (1) ◽  
Author(s):  
Mikkel C Vinding ◽  
Panagiota Tsitsi ◽  
Josefine Waldthaler ◽  
Robert Oostenveld ◽  
Martin Ingvar ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Time Series ◽  
Parkinson's Disease ◽  
Sensorimotor Cortex ◽  
Symptom Severity ◽  
Time Course ◽  
Motor Symptom ◽  
Healthy Controls ◽  
Beta Band ◽  
Band Activity

Abstract Parkinson’s disease is characterized by a gradual loss of dopaminergic neurons, which is associated with altered neuronal activity in the beta-band (13–30 Hz). Assessing beta-band activity typically involves transforming the time-series to get the power of the signal in the frequency domain. Such transformation assumes that the time-series can be reduced to a combination of steady-state sine- and cosine waves. However, recent studies have suggested that this approach masks relevant biophysical features in the beta-band—for example, that the beta-band exhibits transient bursts of high-amplitude activity. In an exploratory study, we used magnetoencephalography to record beta-band activity from the sensorimotor cortex, to characterize how spontaneous cortical beta bursts manifest in Parkinson’s patients on and off dopaminergic medication, and compare this to matched healthy controls. We extracted the time-course of beta-band activity from the sensorimotor cortex and characterized bursts in the signal. We then compared the burst rate, duration, inter-burst interval and peak amplitude between the Parkinson’s patients and healthy controls. Our results show that Parkinson’s patients off medication had a 5–17% lower beta bursts rate compared to healthy controls, while both the duration and the amplitude of the bursts were the same for healthy controls and medicated state of the Parkinson’s patients. These data thus support the view that beta bursts are fundamental underlying features of beta-band activity, and show that changes in cortical beta-band power in Parkinson’s disease can be explained—primarily by changes in the underlying burst rate. Importantly, our results also revealed a relationship between beta burst rate and motor symptom severity in Parkinson’s disease: a lower burst rate scaled with increased severity of bradykinesia and postural/kinetic tremor. Beta burst rate might thus serve as a neuromarker for Parkinson’s disease that can help in the assessment of symptom severity in Parkinson’s disease or in the evaluation of treatment effectiveness.

scholarly journals Top-down beta enhances bottom-up gamma

2016 ◽  
Author(s):  
Craig G. Richter ◽  
William H. Thompson ◽  
Conrado A. Bosman ◽  
Pascal Fries
Keyword(s):  
Gamma Band ◽  
Visual Area ◽  
Beta Band ◽  
Top Down ◽  
Bottom Up ◽  
Area V4 ◽  
Frequency Interaction ◽  
Area 7A ◽  
Alpha Beta ◽  
Band Activity

AbstractSeveral recent studies have demonstrated that the bottom-up signaling of a visual stimulus is subserved by interareal gamma-band synchronization, whereas top-down influences are mediated by alpha-beta band synchronization. These processes may implement top-down control of stimulus processing if top-down and bottom-up mediating rhythms are coupled via cross-frequency interaction. To test this possibility, we investigated Granger-causal influences among awake male macaque primary visual area V1, higher visual area V4 and parietal control area 7a during attentional task performance. Top-down 7a-to-V1 beta-band influences enhanced visually driven V1-to-V4 gamma-band influences. This enhancement was spatially specific and largest when beta-band activity preceded gamma-band activity by ∼0.1 s, suggesting a causal effect of top-down processes on bottom-up processes. We propose that this cross-frequency interaction mechanistically subserves the attentional control of stimulus selection.Significance StatementContemporary research indicates that the alpha-beta frequency band underlies top-down control, while the gamma-band mediates bottom-up stimulus processing. This arrangement inspires an attractive hypothesis, which posits that top-down beta-band influences directly modulate bottom-up gamma band influences via cross-frequency interaction. We evaluate this hypothesis determining that beta-band top-down influences from parietal area 7a to visual area V1 are correlated with bottom-up gamma frequency oscillations from V1 to area V4, in a spatially specific manner, and that this correlation is maximal when top-down activity precedes bottom-up activity. These results show that for top-down processes such as spatial attention, elevated top-down beta-band influences directly enhance feedforward stimulus induced gamma-band processing, leading to enhancement of the selected stimulus.

scholarly journals Bilaterally Reduced Rolandic Beta Band Activity in Minor Stroke Patients

2021 ◽  
Author(s):  
Joshua P Kulasingham ◽  
Christian Brodbeck ◽  
Sheena Khan ◽  
Elisabeth B Marsh ◽  
Jonathan Z Simon
Keyword(s):  
Sensorimotor Cortex ◽  
Reaction Times ◽  
Minor Stroke ◽  
Button Press ◽  
Beta Band ◽  
Stroke Patients ◽  
Potential Biomarker ◽  
Beta Power ◽  
Motor Dexterity ◽  
Band Activity

Objective: Stroke patients with hemiparesis display decreased beta band (13-25 Hz) rolandic activity, correlating to impaired motor function. However, patients without significant weakness, with small lesions far from sensorimotor cortex, nevertheless exhibit bilateral decreased motor dexterity and slowed reaction times. We investigate whether these minor stroke patients also display abnormal beta band activity. Methods: Magnetoencephalographic (MEG) data were collected from nine minor stroke patients (NIHSS < 4) without significant hemiparesis, at ~1 and ~6 months postinfarct, and eight age-similar controls. Rolandic relative beta power during matching tasks and resting state, and Beta Event Related (De)Synchronization (ERD/ERS) during button press responses were analyzed. Results: Regardless of lesion location, patients had significantly reduced relative beta power and ERS compared to controls. Abnormalities persisted over visits, and were present in both ipsi- and contra-lesional hemispheres, consistent with bilateral impairments in motor dexterity and speed. Conclusions: Minor stroke patients without severe weakness display reduced rolandic beta band activity in both hemispheres, which may be linked to bilaterally impaired dexterity and processing speed, implicating global connectivity dysfunction affecting sensorimotor cortex. Significance: Rolandic beta band activity may be a potential biomarker and treatment target, even for minor stroke patients with small lesions far from sensorimotor areas.

The effects of motor skill level and somatosensory input on motor imagery: An fMRI study on basketball free shot

2017 ◽  
Vol 49 (3) ◽  
pp. 307
Author(s):  
Lanlan ZHANG ◽  
Cheng SHEN ◽  
Hua ZHU ◽  
Xuepei LI ◽  
Wen DAI ◽  
...  
Keyword(s):  
Motor Imagery ◽  
Motor Skill ◽  
Skill Level ◽  
Fmri Study ◽  
Somatosensory Input

Neurofeedback Training Protocol Based on Selecting Distinctive Features to Treat or Reduce ADHD Symptoms

2021 ◽  
pp. 155005942110334
Author(s):  
Parham Jalali ◽  
Nasrin Sho’ouri
Keyword(s):  
Treatment Protocol ◽  
Adhd Symptoms ◽  
Eeg Signals ◽  
Beta Band ◽  
Distinctive Features ◽  
Children With Adhd ◽  
Hyperactivity Disorder ◽  
Distinguishing Features ◽  
Band Activity ◽  
Training Protocol

Resent research has shown that electroencephalography (EEG) theta/beta ratio (TBR) in cases with attention deficit hyperactivity disorder (ADHD) has thus far been reported lower than that in healthy individuals. Accordingly, utilizing EEG-TBR as a biomarker to diagnose ADHD has been called into question. Besides, employing known protocol to reduce EEG-TBR in the vertex (Cz) channel to treat ADHD via neurofeedback (NFB) has been doubted. The present study was to propose a new NFB treatment protocol to manage ADHD using EEG signals from 30 healthy controls and 30 children with ADHD through an attention-based task and to calculate relative power in their different frequency bands. Then, the most significant distinguishing features of EEG signals from both groups were determined via a genetic algorithm (GA). The results revealed that EEG-TBR values in children with ADHD were lower compared with those in healthy peers; however, such a difference was not statistically significant. Likewise, inhibiting alpha band activity and enhancing delta one in F7 or T5 channels was proposed as a new NFB treatment protocol for ADHD. No significant increase in EEG-TBR in the Cz channel among children with ADHD casts doubt on the effectiveness of using EEG-TBR inhibitory protocols in the Cz channel. Consequently, it was proposed to apply the new protocol along with reinforced beta-band activity to treat or reduce ADHD symptoms.

scholarly journals Source Detection and Functional Connectivity of the Sensorimotor Cortex during Actual and Imaginary Limb Movement: A Preliminary Study on the Implementation of eConnectome in Motor Imagery Protocols

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Alkinoos Athanasiou ◽  
Chrysa Lithari ◽  
Konstantina Kalogianni ◽  
Manousos A. Klados ◽  
Panagiotis D. Bamidis
Keyword(s):  
Functional Connectivity ◽  
Motor Imagery ◽  
Sensorimotor Cortex ◽  
Mu Rhythm ◽  
Source Detection ◽  
Motor Execution ◽  
Motor Tasks ◽  
Computer Interfaces ◽  
Preliminary Study ◽  
Real Hand

Introduction. Sensorimotor cortex is activated similarly during motor execution and motor imagery. The study of functional connectivity networks (FCNs) aims at successfully modeling the dynamics of information flow between cortical areas.Materials and Methods. Seven healthy subjects performed 4 motor tasks (real foot, imaginary foot, real hand, and imaginary hand movements), while electroencephalography was recorded over the sensorimotor cortex. Event-Related Desynchronization/Synchronization (ERD/ERS) of the mu-rhythm was used to evaluate MI performance. Source detection and FCNs were studied with eConnectome.Results and Discussion. Four subjects produced similar ERD/ERS patterns between motor execution and imagery during both hand and foot tasks, 2 subjects only during hand tasks, and 1 subject only during foot tasks. All subjects showed the expected brain activation in well-performed MI tasks, facilitating cortical source estimation. Preliminary functional connectivity analysis shows formation of networks on the sensorimotor cortex during motor imagery and execution.Conclusions. Cortex activation maps depict sensorimotor cortex activation, while similar functional connectivity networks are formed in the sensorimotor cortex both during actual and imaginary movements. eConnectome is demonstrated as an effective tool for the study of cortex activation and FCN. The implementation of FCN in motor imagery could induce promising advancements in Brain Computer Interfaces.

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