Article
Engineering, Biomedical
Yihua Zhong, Xu Zhang, Jonathan Beckel, William C. de Groat, Changfeng Tai
Summary: A new axonal conduction model was used to analyze the interaction between intracellular sodium concentration and membrane potential oscillation in axonal conduction block induced by high-frequency biphasic stimulation. The results show that the block duration can be shortened by increasing the HFBS intensity, and the block can be maintained if the intensity is above a certain threshold.
JOURNAL OF NEURAL ENGINEERING
(2022)
Article
Medicine, Research & Experimental
Yihua Zhong, Jicheng Wang, Jonathan Beckel, William C. de Groat, Changfeng Tai
Summary: This study reveals the possible ionic mechanisms underlying poststimulation block induced by high-frequency biphasic stimulation, including short-duration and long-duration block. By adjusting stimulation frequency and duration, the block effect can be controlled.
Article
Mathematical & Computational Biology
Yihua Zhong, Jicheng Wang, Jonathan Beckel, William C. de Groat, Changfeng Tai
Summary: This modeling study aimed to develop a novel method to block nerve conduction using high frequency biphasic stimulation without generating initial action potentials. The simulation analysis demonstrated that step-increases in sub-threshold intensity during HFBS can successfully block axonal conduction.
JOURNAL OF COMPUTATIONAL NEUROSCIENCE
(2022)
Article
Medicine, General & Internal
David Martin-Caro Alvarez, Diego Serrano-Munoz, Juan Jose Fernandez-Perez, Julio Gomez-Soriano, Juan Avendano-Coy
Summary: This study investigated the effects of high-frequency alternating currents (HFAC) on the peripheral nervous system in healthy volunteers. The results showed that percutaneous stimulation with 20 kHz HFAC led to a reversible reduction in strength.
JOURNAL OF CLINICAL MEDICINE
(2022)
Article
Medicine, Research & Experimental
Jialiang Chen, Yihua Zhong, Jicheng Wang, Bing Shen, Jonathan Beckel, William C. de Groat, Changfeng Tai
Summary: This study investigates the impact of temperature on nerve conduction block induced by high-frequency (kHz) stimulation. Results show that at a lower temperature of 15 degrees C, both 2- and 10-kHz stimulations caused an initial muscle contraction followed by nerve block. The threshold for acute block was significantly higher for 10 kHz compared to 2 kHz. However, at a higher temperature of 20 degrees C, the threshold for acute block with 10-kHz stimulation decreased, while 2-kHz stimulation induced a tonic muscle contraction and a poststimulation block.
Article
Neurosciences
David Martin-Caro Alvarez, Diego Serrano-Munoz, Juan Jose Fernandez-Perez, Julio Gomez-Soriano, Juan Avendano-Coy
Summary: This study evaluated the effect of percutaneous HFAC at 30 kHz on sensory-motor nerve conduction in healthy volunteers. The results showed that the active group had increased pressure pain threshold during and after the stimulation compared to the sham group. Participants in the active group also reported more feelings of numbness and heaviness. No intergroup differences were observed in the remaining outcome variables.
FRONTIERS IN NEUROSCIENCE
(2023)
Article
Neurosciences
Victoria Gonzalez Sabater, Mark Rigby, Juan Burrone
Summary: In this study, the initiation and propagation of action potentials (APs) along the axon were investigated using genetically encoded voltage indicators (GEVIs) in dissociated hippocampal neurons from rat embryos. It was found that APs became sharper and exhibited greater fidelity as they traveled towards distal axonal domains. Blocking voltage-gated potassium channels (K-v) resulted in an increase in AP width, especially in distal locations, suggesting that higher levels of Kv channel activity in distal axons contribute to maintaining AP fidelity.
JOURNAL OF NEUROSCIENCE
(2021)
Article
Engineering, Biomedical
Luis Vargas, Eric D. Musselman, Warren M. Grill, Xiaogang Hu
Summary: This study developed a subthreshold high-frequency stimulation waveform to activate axons asynchronously, aiming to achieve finer control of muscle forces. Results from both experiments and simulations demonstrated that the stimulation waveform could induce asynchronous firing patterns of neurons and provide more stable control of muscle forces.
JOURNAL OF NEURAL ENGINEERING
(2023)
Article
Engineering, Biomedical
Jianan Jian, Jonathan M. Beckel, William C. de Groat, Changfeng Tai
Summary: A new axonal conduction model that includes ion pump activity and allows for changes in ion concentrations is developed. The model successfully simulates action potential generation, propagation, and acute DC block, as well as the post-stimulation block phenomenon observed in animal studies. The study highlights the importance of ion concentrations and ion pump activity in post-stimulation block induced by long-duration DC stimulation.
IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING
(2023)
Article
Neurosciences
Meifan Chen, Laura Ingle, Erik J. Plautz, Xiangmei Kong, Rui Tang, Neil Ghosh, Megan K. Romprey, William K. Fenske, Mark P. Goldberg
Summary: Injury to the central nervous system in adult mammals induces collateral axon sprouting, which can facilitate neural recovery. This study investigates the role of reactive astrocytes in regulating axon sprouting after stroke in the mouse spinal cord. The findings suggest that stimulating astrocyte reactivity can enhance sprouting of the corticospinal axons, highlighting the potential of engineering astrocytes for neural repair.
FRONTIERS IN CELLULAR NEUROSCIENCE
(2022)
Article
Neurosciences
Sogand Sajedi, Andreas Fellner, Paul Werginz, Frank Rattay
Summary: Electric micro-stimulation of the nervous system is a method used for restoring various body functions, but overstimulation can hinder optimal neuro-rehabilitation. The impact of upper threshold (UT) in micro-stimulation has been studied, showing differences in action potential initiation among different cell types such as retinal ganglion cells and layer 5 pyramidal cells. Understanding the stimulation window that can reliably activate target neurons is crucial for the future development of neuroprostheses.
FRONTIERS IN CELLULAR NEUROSCIENCE
(2021)
Article
Medicine, Research & Experimental
Katherine Shapiro, Wenbin Guo, Kody Armann, Natalie Pace, Bing Shen, Jicheng Wang, Jonathan Beckel, William de Groat, Changfeng Tai
Summary: The study found that low-frequency biphasic stimulation can induce poststimulation block, which is reversible, and the duration of stimulation required for inducing block increases with frequency. The results of this study provide an opportunity for the development of new neuromodulation devices.
Article
Neurosciences
Fumeng Zheng, Haruyuki Kamiya
Summary: Modification of axonal excitability affects information transfer in the brain, but the functional significance of this modulation remains unclear. This study focused on the activity-dependent broadening of action potentials in the hippocampal mossy fibers and found that it is dependent on the inactivation of axonal K+ channels. Computer simulations showed that removing the inactivation process abolished the use-dependent broadening of action potentials. This highlights the critical role of K+ channel inactivation in regulating axonal excitability and short-term plasticity at this synapse.
FRONTIERS IN CELLULAR NEUROSCIENCE
(2023)
Article
Engineering, Biomedical
L. Savannah Dewberry, Alexander B. Dru, Maxwell Gravenstine, Brian Nguyen, James Anderson, Sasha Vaziri, Daniel J. Hoh, Kyle D. Allen, Kevin J. Otto
Summary: The study showed that HF block can rapidly reduce tactile sensitivity in a limb with neuropathic injury. No significant increase in gait disability was observed during HF block.
JOURNAL OF NEURAL ENGINEERING
(2021)
Article
Biochemistry & Molecular Biology
Sreerag Othayoth Vasu, Hanoch Kaphzan
Summary: Transcranial direct current stimulation (tDCS) is a technique that modulates spontaneous neurotransmitter release by regulating calcium channels in axon terminals, primarily through P/Q and N-type calcium channels.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)