Modulating motor function after stroke: Differential effects of high-frequency rTMS on movement kinematics and neural activity in subcortical and cortical MCA stroke

2008 ◽  
Vol 39 (01) ◽  
Author(s):  
M Ameli ◽  
C Grefkes ◽  
F Kemper ◽  
L Wang ◽  
M Dafotakis ◽  
...  
Keyword(s):  
Motor Function ◽  
Neural Activity ◽  
High Frequency ◽  
Movement Kinematics ◽  
Differential Effects

scholarly journals Neurostimulation stabilizes spiking neural networks by disrupting seizure-like oscillatory transitions

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Scott Rich ◽  
Axel Hutt ◽  
Frances K. Skinner ◽  
Taufik A. Valiante ◽  
Jérémie Lefebvre
Keyword(s):  
Neural Activity ◽  
High Frequency ◽  
Network Dynamics ◽  
Mean Field ◽  
High Frequency Stimulation ◽  
Seizure Onset ◽  
Oscillatory Dynamics ◽  
Seizure State ◽  
Frequency Stimulation ◽  
Mathematical Analyses

Abstract An improved understanding of the mechanisms underlying neuromodulatory approaches to mitigate seizure onset is needed to identify clinical targets for the treatment of epilepsy. Using a Wilson–Cowan-motivated network of inhibitory and excitatory populations, we examined the role played by intrinsic and extrinsic stimuli on the network’s predisposition to sudden transitions into oscillatory dynamics, similar to the transition to the seizure state. Our joint computational and mathematical analyses revealed that such stimuli, be they noisy or periodic in nature, exert a stabilizing influence on network responses, disrupting the development of such oscillations. Based on a combination of numerical simulations and mean-field analyses, our results suggest that high variance and/or high frequency stimulation waveforms can prevent multi-stability, a mathematical harbinger of sudden changes in network dynamics. By tuning the neurons’ responses to input, stimuli stabilize network dynamics away from these transitions. Furthermore, our research shows that such stabilization of neural activity occurs through a selective recruitment of inhibitory cells, providing a theoretical undergird for the known key role these cells play in both the healthy and diseased brain. Taken together, these findings provide new vistas on neuromodulatory approaches to stabilize neural microcircuit activity.

Neurostimulation in alcohol dependence: The effect of repetitive transcranial magnetic stimulation on brain function and craving

2016 ◽  
Vol 33 (S1) ◽  
pp. S59-S59
Author(s):  
J. Jansen ◽  
O. van den Heuvel ◽  
Y. van der Werf ◽  
S. De Wit ◽  
D. Veltman ◽  
...  
Keyword(s):  
Emotion Regulation ◽  
Transcranial Magnetic Stimulation ◽  
Alcohol Dependence ◽  
Neural Activity ◽  
High Frequency ◽  
Magnetic Stimulation ◽  
Negative Emotion ◽  
Repetitive Transcranial Magnetic Stimulation ◽  
Anterior Cingulate ◽  
Fmri Session

BackgroundAlcohol dependence has long been related to impaired processing and handling of negative emotions. This is the first study to compare emotion regulation (ER) at a behavioral and neural level in alcohol dependent patients (ADPs) and healthy controls (HCs). It also examines the effects of high-frequency repetitive transcranial magnetic stimulation (rTMS) on ER abilities and related craving levels in ADPs.MethodThirty-six ADPs and 32 HCs matched on age, sex, and education, were included in a within-subject fixed-order study with one functional magnetic resonance imaging (fMRI) session and one rTMS plus fMRI session, with high-frequency (10 Hz) rTMS over the right dorsolateral prefrontal cortex (dlPFC). An fMRI emotion regulation task (ERT) was administered during both sessions and craving was measured before and after each ERT.ResultsADPs were impaired in the regulation of negative emotion and showed a higher activation of ER related brain areas compared to HCs. Furthermore, active rTMS improved ER abilities in both ADPs and HCs, but was accompanied by a decrease in anterior cingulate and left dlPFC activity only in ADPs. In addition, the ERT-induced increase in craving levels in ADPs was trend-significantly reduced by active rTMS, with a large effect size.ConclusionsADPs are impaired in the regulation of negative emotion and show enhanced neural activity in the ER brain circuit. High-frequency rTMS improves ER in ADPs and HCs and normalizes neural activity and tends to reduce craving in ADPs. Future studies are needed to test the long-term effects of (multiple session) rTMS on ER, craving, and drinking.Disclosure of interestThe authors have not supplied their declaration of competing interest.

Differential effects of reboxetine and citalopram on hand-motor function in patients suffering from major depression

2004 ◽  
Vol 178 (1) ◽  
pp. 58-66 ◽  
Author(s):  
Ulrich Hegerl ◽  
Roland Mergl ◽  
Verena Henkel ◽  
Oliver Pogarell ◽  
Florian M�ller-Siecheneder ◽  
...  
Keyword(s):  
Major Depression ◽  
Motor Function ◽  
Differential Effects

Abnormal resting-state connectivity of motor and cognitive networks in early manifest Huntington's disease

2014 ◽  
Vol 44 (15) ◽  
pp. 3341-3356 ◽  
Author(s):  
R. C. Wolf ◽  
F. Sambataro ◽  
N. Vasic ◽  
M. S. Depping ◽  
P. A. Thomann ◽  
...  
Keyword(s):  
Huntington's Disease ◽  
Huntington’S Disease ◽  
Motor Function ◽  
Neural Activity ◽  
Resting State ◽  
Brain Atrophy ◽  
Clinical Symptoms ◽  
Resting State Fmri ◽  
Cognitive Networks ◽  
The Impact

Background.Functional magnetic resonance imaging (fMRI) of multiple neural networks during the brain's ‘resting state’ could facilitate biomarker development in patients with Huntington's disease (HD) and may provide new insights into the relationship between neural dysfunction and clinical symptoms. To date, however, very few studies have examined the functional integrity of multiple resting state networks (RSNs) in manifest HD, and even less is known about whether concomitant brain atrophy affects neural activity in patients.Method.Using MRI, we investigated brain structure and RSN function in patients with early HD (n = 20) and healthy controls (n = 20). For resting-state fMRI data a group-independent component analysis identified spatiotemporally distinct patterns of motor and prefrontal RSNs of interest. We used voxel-based morphometry to assess regional brain atrophy, and ‘biological parametric mapping’ analyses to investigate the impact of atrophy on neural activity.Results.Compared with controls, patients showed connectivity changes within distinct neural systems including lateral prefrontal, supplementary motor, thalamic, cingulate, temporal and parietal regions. In patients, supplementary motor area and cingulate cortex connectivity indices were associated with measures of motor function, whereas lateral prefrontal connectivity was associated with cognition.Conclusions.This study provides evidence for aberrant connectivity of RSNs associated with motor function and cognition in early manifest HD when controlling for brain atrophy. This suggests clinically relevant changes of RSN activity in the presence of HD-associated cortical and subcortical structural abnormalities.

Sign in / Sign up

Export Citation Format

Share Document