Mechanical or electrical stimulations in the area of the mouth evoke two phases of inhibition in the masseter muscle (early and late inhibitory reflex, also called masseter silent periods). The question whether the afferents of the human masseter inhibitory reflex are nociceptive or non-nociceptive has not yet been settled. We showed that an innocuous stimulus, such as a fine jet of saline directed to the lips of healthy humans, evokes an early and a late masseter inhibitory reflex, similar to those following electrical stimulation. We measured the efferent and afferent delay of the masseter early inhibitory reflex in patients submitted to intracranial stimulation of the motor and sensory trigeminal root, and found that the reflex afferents belong to the intermediately-fast conducting fibre group.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1007/BF00275005 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
A membrane-targeted photoswitch restores physiological ON/OFF responses to light in the degenerate retina.
Nat Commun
January 2025
Center for Synaptic Neuroscience, Istituto Italiano di Tecnologia, Genova, Italy.
The lack of effective therapies for visual restoration in Retinitis pigmentosa and macular degeneration has led to the development of new strategies, such as optogenetics and retinal prostheses. However, visual restoration is poor due to the massive light-evoked activation of retinal neurons, regardless of the segregation of visual information in ON and OFF channels, which is essential for contrast sensitivity and spatial resolution. Here, we show that Ziapin2, a membrane photoswitch that modulates neuronal capacitance and excitability in a light-dependent manner, is capable of reinstating, in mouse and rat genetic models of photoreceptor degeneration, brisk and sluggish ON, OFF, and ON-OFF responses in retinal ganglion cells evoked by full-field stimuli, with reactivation of their excitatory and inhibitory conductances.
View Article and Find Full Text PDFPathophysiology and Management Strategies for Post-Stroke Spasticity: An Update Review.
Int J Mol Sci
January 2025
School of Pharmacy, Hunan University of Chinese Medicine, Changsha 410208, China.
Post-stroke spasticity (PSS), characterized by a velocity-dependent increase in muscle tone and exaggerated reflexes, affects a significant portion of stroke patients and presents a substantial obstacle to post-stroke rehabilitation. Effective management and treatment for PSS remains a significant clinical challenge in the interdisciplinary aspect depending on the understanding of its etiologies and pathophysiology. We systematically review the relevant literature and provide the main pathogenic hypotheses: alterations in the balance of excitatory and inhibitory inputs to the descending pathway or the spinal circuit, which are secondary to cortical and subcortical ischemic or hemorrhagic injury, lead to disinhibition of the stretch reflex and increased muscle tone.
View Article and Find Full Text PDFOptimizing transcutaneous spinal stimulation: excitability of evoked spinal reflexes is dependent on electrode montage.
J Neuroeng Rehabil
January 2025
Hulse Spinal Cord Injury Research Lab, Shepherd Center, 2020 Peachtree Road NW, Atlanta, GA, USA.
Background: There is growing interest in use of transcutaneous spinal stimulation (TSS) for people with neurologic conditions both to augment volitional control (by facilitating motoneuron excitability), and to decrease spasticity (by activating inhibitory networks). Various electrode montages are used during TSS, with little understanding of how electrode position influences spinal circuit activation. We sought to identify the thoracolumbar electrode montage associated with the most robust activation of spinal circuits by comparing posterior root-muscle reflexes (PRM reflexes) elicited by 6 montages.
View Article and Find Full Text PDFEffects of Age on the Bone-Conduction Amplitude-Modulated cVEMP Temporal Modulation Transfer Function.
Ear Hear
December 2024
Department of Communication Sciences and Disorders, James Madison University, Harrisonburg, Virginia, USA.
Objectives: Cervical vestibular evoked myogenic potentials (cVEMPs) reflect saccular stimulation that results in an inhibitory muscle reflex recorded over the sternocleidomastoid muscle. These responses are utilized to study basic vestibular functions and are also applied clinically. Traditionally, cVEMPs have utilized transient stimuli such as clicks and tonebursts to evoke onset responses.
View Article and Find Full Text PDFThe role of deep layer superior colliculus neurons in prepulse inhibition and the impact of spatial separation in male rats.
Neuroscience
December 2024
School of Psychological and Cognitive Sciences, Peking University, Beijing 100080, China.
Prepulse inhibition (PPI) refers to the phenomenon in which a weak sensory stimulus before a strong one significantly reduces the startle reflex caused by the strong stimulus. Perceptual spatial separation, a phenomenon where auditory cues from the prepulse and background noise are distinguished in space, has been shown to enhance PPI. This study aims to investigate the neural modulation mechanisms of PPI by the spatial separation between the prepulse stimulus and background noise, particularly in the deep superior colliculus (deepSC).
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!