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05:52
Measuring the Induced Membrane Voltage with Di-8-ANEPPS
Published on: November 19, 2009
Transmembrane potential generated by a magnetically induced transverse electric field in a cylindrical axonal model
Hui Ye1, Marija Cotic, Michael G Fehlings
1Toronto Western Research Institute, University Health Network, Toronto, ON, Canada. hye@uhnresearch.ca
Medical & Biological Engineering & Computing
|November 11, 2010
Summary
Transverse magnetic fields can activate nerve axons by inducing transmembrane potentials. Axon polarization depends on magnetic field properties and the axon
Area of Science:
- Neuroscience
- Biophysics
- Electromagnetic Induction
Background:
- Electrical stimulation of nerve axons typically relies on parallel electric fields.
- Transverse electric fields, induced by time-varying magnetic fields, can also activate axons.
- Understanding transmembrane potential induction is key to magnetic stimulation efficacy.
Purpose of the Study:
- Investigate factors influencing transmembrane potential during magnetic stimulation.
- Analyze the role of transverse magnetic fields in axonal activation.
- Provide a mathematical model for transverse field-induced potentials.
Main Methods:
- Developed an analytic expression for transmembrane potential.
- Utilized an unmyelinated axon model.
- Analyzed spatially uniform, time-varying magnetic stimulation.
Main Results:
- Derived an analytic solution for transmembrane potential.
- Demonstrated dependence on magnetic field properties (orientation, magnitude, frequency).
- Showed dependence on axon geometry (radius, membrane thickness) and electrical properties (conductivity, permittivity).
Conclusions:
- Transverse magnetic fields are effective in inducing axonal transmembrane potentials.
- Axonal activation efficacy depends on both magnetic field characteristics and intrinsic tissue properties.
- The derived analytic solution can enhance magnetic stimulation models.
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