Document Type
Article
Publication Date
1-1-2019
Abstract
Objective. Thermal block of action potential conduction using infrared lasers is a new modality for manipulating neural activity. It could be used for analysis of the nervous system and for therapeutic applications. We sought to understand the mechanisms of thermal block. Approach. To analyze the mechanisms of thermal block, we studied both the original Hodgkin/Huxley model, and a version modified to more accurately match experimental data on thermal responses in the squid giant axon. Main results. Both the original and modified models suggested that thermal block, especially at higher temperatures, is primarily due to a depolarization-activated hyperpolarization as increased temperature leads to faster activation of voltage-gated potassium ion channels. The minimum length needed to block an axon scaled with the square root of the axon's diameter. Significance. The results suggest that voltagedependent potassium ion channels play a major role in thermal block, and that relatively short lengths of axon could be thermally manipulated to selectively block fine, unmyelinated axons, such as C fibers, that carry pain and other sensory information.
Keywords
computational model, infrared neural inhibition, scaling, squid giant axon, thermal block, unmyelinated axons, voltage-gated potassium channels
Language
English
Publication Title
Journal of Neural Engineering
Grant
R56-NS087249
Rights
© 2019 The Author(s). This is an open access article under the CC BY license (https://creativecommons.org/licenses/by/3.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.
Recommended Citation
Ganguly M, Jenkins MW, Jansen ED, Chiel HJ. Thermal block of action potentials is primarily due to voltage-dependent potassium currents: a modeling study. J Neural Eng. 2019 Jun;16(3):036020. doi: 10.1088/1741-2552/ab131b. Epub 2019 Mar 25. PMID: 30909171; PMCID: PMC11190670.
Manuscript Version
Final Publisher Version