AI Article Synopsis
Article Abstract
Objective: Cervical propriospinal premotoneurons (PN) relay descending motor commands and integrate peripheral afferent feedback. Effects of anodal transcranial direct current stimulation (a-tDCS) on propriospinal excitability in the upper limbs are unknown.
Methods: Healthy right-handed adults received a-tDCS or sham tDCS over primary motor cortex (M1) at 1mA (Experiment 1, n=18) or 2mA current intensity (Experiment 2, n=15). Propriospinal excitability was assessed by suppression of background electromyography (EMG) in extensor carpi radialis (ECR) from electrical stimulation of the superficial radial nerve during bilateral (Experiment 1 and 2) or unilateral (Experiment 2 only) activation of the left and/or right ECR. EMG suppression could be attributed to an early propriospinal component and late cortical component. Motor evoked potentials (MEP) were obtained as a manipulation check.
Results: Before tDCS, propriospinal-mediated cutaneous-induced suppression was present in each arm for early and late components. ECR MEP amplitude increased after 1mA, but not 2mA, a-tDCS. Neither 1mA nor 2mA a-tDCS modulated either component of ipsilateral or contralateral propriospinal excitability during bilateral or unilateral tasks.
Conclusions: Propriospinal-mediated cutaneous-induced suppression was not modulated by a-tDCS in healthy adults.
Significance: Reporting non-significant findings is paramount for the development of clinically-relevant tDCS protocols.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.clinph.2017.06.035 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Diagnostic Utility of Clinical Neurophysiology in Jerky Movement Disorders: A Review from the MDS Clinical Neurophysiology Study Group.
Mov Disord Clin Pract
December 2024
Krembil Research Institute, University Health Network, University of Toronto, Toronto, Ontario, Canada.
Background: Myoclonus and other jerky movement disorders are hyperkinetic disorders, the diagnosis of which heavily relies on clinical neurophysiological testing. However, formal diagnostic criteria are lacking, and recently the utility and reliability of these tests have been questioned.
Objective: The aim of this review was to assess the utilization of clinical neurophysiology testing to identify possible gaps and boundaries that might guide the development of new methods for a more precise diagnosis and in-depth understanding of myoclonus.
While considerable progress has been made in understanding the neuronal circuits that underlie the patterning of locomotor behaviours such as walking, less is known about the circuits that amplify motoneuron output to enable adaptable increases in muscle force across different locomotor intensities. Here, we demonstrate that an excitatory propriospinal neuron population (V3 neurons, Sim1 ) forms a large part of the total excitatory interneuron input to motoneurons (∼20%) across all hindlimb muscles. Additionally, V3 neurons make extensive connections among themselves and with other excitatory premotor neurons (such as V2a neurons).
View Article and Find Full Text PDFLocomotor-related propriospinal V3 neurons produce primary afferent depolarization and modulate sensory transmission to motoneurons.
J Neurophysiol
October 2023
Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada.
When a muscle is stretched, sensory feedback not only causes reflexes but also leads to a depolarization of sensory afferents throughout the spinal cord (primary afferent depolarization, PAD), readying the whole limb for further disturbances. This sensory-evoked PAD is thought to be mediated by a trisynaptic circuit, where sensory input activates first-order excitatory neurons that activate GABAergic neurons that in turn activate GABA receptors on afferents to cause PAD, though the identity of these first-order neurons is unclear. Here, we show that these first-order neurons include propriospinal V3 neurons, as they receive extensive sensory input and in turn innervate GABAergic neurons that cause PAD, because optogenetic activation or inhibition of V3 neurons in mice mimics or inhibits sensory-evoked PAD, respectively.
View Article and Find Full Text PDFRestless Legs Syndrome and Other Common Sleep-Related Movement Disorders.
Continuum (Minneap Minn)
August 2023
Objective: This article reviews common sleep-related movement disorders, including their clinical description, epidemiology, pathophysiology (if known), and evaluation and management strategies. This article will provide the reader with a good foundation for approaching concerns that are suggestive of sleep-related movement disorders to properly evaluate and manage these conditions.
Latest Developments: α2δ Ligands, such as gabapentin enacarbil, can be used for the initial treatment of restless legs syndrome (RLS) or in those who cannot tolerate, or have developed augmentation to, dopamine agonists.
[A case of idiopathic propriospinal myoclonus accompanied by giant somatosensory evoked potential].
Rinsho Shinkeigaku
November 2022
Department of Neurology, Uji Obaku Hospital.
A 41-year-old man visited our clinic because of headache with fever, suggestive of aseptic meningitis. His headache improved in a few days. His neurological examination showed positive jolt accentuation and myoclonus of the thoracoabdominal muscles extending to extremities upon patellar tapping.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!