How does the myelin sheath's thickness affect the speed of action potential in neurons?
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The thickness of the myelin sheath significantly impacts the speed of action potential propagation in neurons. Thicker myelin sheaths, typically found in large-distance axonal connections or fast-spiking interneurons, enhance conduction velocity and energy efficiency . Myelin acts as an electrical insulator, confining action potentials to nodes of Ranvier in myelinated neurons, controlling their shapes, timings, and propagation speeds . In demyelinated axons, compensatory processes like mitochondrial mass increase and a switch from saltatory to continuous propagation are required to maintain axon functionality, albeit at the cost of reduced speed and increased energy expenditure . Lack of myelin, as seen in demyelinating diseases, exposes potassium channels to induce action potentials, highlighting the role of myelin in limiting hyperexcitability .
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| Papers (5) | Insight |
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| Thicker myelin sheaths on axons increase action potential speed by enhancing conduction velocity and energy efficiency, crucial for synchronizing neuronal networks during gamma-band oscillations. | |
| The myelin sheath's thickness is tailored to axon diameter, maximizing action potential speed. Inappropriate thickness post-injury may compromise function, highlighting the importance of precise myelin regulation. | |
| The myelin sheath's thickness influences the speed of action potential propagation in neurons by affecting the distribution of membrane potential through non-local effects in myelinated neurons. | |
06 Dec 2019 | The myelin sheath's thickness increases the speed of action potentials by preventing potassium ion tunneling through closed channels, maintaining spatiotemporal fidelity and limiting hyperexcitability in neurons. |
| Myelin sheath thickness, regulated by oligodendrocyte calcium signaling, can precisely tune conduction velocity by sculpting sheath morphology, impacting the speed of action potential propagation in neurons. |
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