Deep brain stimulation (DBS) implanted in different basal ganglia nuclei regulates the dysfunctional neuronal circuits and improves symptoms in movement disorders. However, the understanding of the neurophysiological mechanism of DBS is at an early stage. Transcranial magnetic stimulation (TMS) can be used safely in movement disorder patients with DBS, and can shed light on how DBS works. DBS at a therapeutic setting normalizes the abnormal motor cortical excitability measured with motor evoked potentials (MEP) produced by primary motor cortical TMS. Abnormal intracortical circuits in the motor cortex tested with paired-pulse TMS paradigm also show normalization with DBS. These changes are accompanied with improvements in symptoms after chronic DBS. Single-pulse DBS produces cortical evoked potentials recorded by electroencephalography at specific latencies and modulates motor cortical excitability at certain time intervals measured with MEP. Combination of basal ganglia DBS with motor cortical TMS at stimulus intervals consistent with the latency of cortical evoked potentials delivered in a repetitive mode produces plastic changes in the primary motor cortex. TMS can be used to examine the effects of open and closed loop DBS. Patterned DBS and TMS delivered in a repetitive mode may be developed as a new therapeutic method for movement disorder patients.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6411433 | PMC |
http://dx.doi.org/10.1016/j.clinph.2018.10.020 | DOI Listing |
Exp Physiol
January 2025
Centre for Healthy Ageing, Health Futures Institute, Murdoch University, Perth, Australia.
Blood flow restriction (BFR) combined with low work rate exercise can enhance muscular and cardiovascular fitness. However, whether neural mechanisms mediate these enhancements remains unknown. This study examined changes in corticospinal excitability and motor cortical inhibition following arm cycle ergometry with and without BFR.
View Article and Find Full Text PDFHum Brain Mapp
February 2025
Department of Radiology, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland.
In contrast to blood-oxygenation level-dependent (BOLD) functional MRI (fMRI), which relies on changes in blood flow and oxygenation levels to infer brain activity, diffusion fMRI (DfMRI) investigates brain dynamics by monitoring alterations in the apparent diffusion coefficient (ADC) of water. These ADC changes may arise from fluctuations in neuronal morphology, providing a distinctive perspective on neural activity. The potential of ADC as an fMRI contrast (ADC-fMRI) lies in its capacity to reveal neural activity independently of neurovascular coupling, thus yielding complementary insights into brain function.
View Article and Find Full Text PDFNeurosci Lett
January 2025
División de Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico. Electronic address:
Parkinson's disease (PD) is a neurodegenerative disorder characterized by progressive loss of dopaminergic neurons in the substantia nigra pars compacta, leading to significant motor and non-motor symptoms. Beta oscillations in cortical areas are a pathognomonic sign. Here we ask whether these oscillations can be recorded in in vitro cortical tissue despite severing the cortico-basal ganglia-thalamo-cortical loop.
View Article and Find Full Text PDFJ Biophotonics
January 2025
School of Rehabilitation Science, Shanghai University of Traditional Chinese Medicine, Shanghai, China.
Motor dysfunction of the upper limbs following a stroke predominantly arises from abnormal motor patterning caused by the disrupted balance of inter-cortical communication within motor-associated cortical regions. Temporal analysis offers a more precise reflection of the cortical functional state in affected patients. This study employed fNIRS to capture hemodynamic responses among 20 stroke patients and 19 healthy controls in both resting and Baduanjin task state.
View Article and Find Full Text PDFBiomed Phys Eng Express
January 2025
F. Joseph Halcomb III, MD, Department of Biomedical Engineering, University of Kentucky, 143 Graham Ave., Lexington, Kentucky, 40506, UNITED STATES.
Brain-computer interfaces (BCIs) offer disabled individuals the means to interact with devices by decoding the electroencephalogram (EEG). However, decoding intent in fine motor tasks can be challenging, especially in stroke survivors with cortical lesions. Here, we attempt to decode graded finger extension from the EEG in stroke patients with left-hand paresis and healthy controls.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!