Abstract
In this study, we used a computer simulation to investigate the nerve excitation processes of the nerve axon in an inhomogeneous volume conductor in magnetic stimulation. We assumed that the nerve axon was located in an inhomogeneous conducting medium with two regions having different conductivities that simulate different tissue types. The distribution of induced electric fields was calculated with the finite element method. The nerve fiber was modeled after equivalent electrical circuits having active nodes of Ranvier. We observed the excitation threshold when the coil current waveforms and direction are changed with varying the electrical properties of the tissue. The simulation results show that the threshold is lower when biphasic waveforms are used and that the optimal current direction depends on tissue conductivity. The results also suggest that the nerve is excited even when the coil current flow is perpendicular to the axon in inhomogeneous conducting media. The results in this study give useful information to explain the experimental results in magnetic stimulation of the brain.
| Original language | English |
|---|---|
| Article number | 07B304 |
| Journal | Journal of Applied Physics |
| Volume | 105 |
| Issue number | 7 |
| DOIs | |
| Publication status | Published - 2009 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Physics and Astronomy(all)
Cite this
Effects of stimulus parameters and tissue inhomogeneity on nerve excitation processes in magnetic stimulation of the brain : A simulation study. / Hyodo, Akira; Hayami, Takehito; Tsuyama, Seichi; Iramina, Keiji; Ueno, Shoogo.
In: Journal of Applied Physics, Vol. 105, No. 7, 07B304, 2009.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Effects of stimulus parameters and tissue inhomogeneity on nerve excitation processes in magnetic stimulation of the brain
T2 - A simulation study
AU - Hyodo, Akira
AU - Hayami, Takehito
AU - Tsuyama, Seichi
AU - Iramina, Keiji
AU - Ueno, Shoogo
PY - 2009
Y1 - 2009
N2 - In this study, we used a computer simulation to investigate the nerve excitation processes of the nerve axon in an inhomogeneous volume conductor in magnetic stimulation. We assumed that the nerve axon was located in an inhomogeneous conducting medium with two regions having different conductivities that simulate different tissue types. The distribution of induced electric fields was calculated with the finite element method. The nerve fiber was modeled after equivalent electrical circuits having active nodes of Ranvier. We observed the excitation threshold when the coil current waveforms and direction are changed with varying the electrical properties of the tissue. The simulation results show that the threshold is lower when biphasic waveforms are used and that the optimal current direction depends on tissue conductivity. The results also suggest that the nerve is excited even when the coil current flow is perpendicular to the axon in inhomogeneous conducting media. The results in this study give useful information to explain the experimental results in magnetic stimulation of the brain.
AB - In this study, we used a computer simulation to investigate the nerve excitation processes of the nerve axon in an inhomogeneous volume conductor in magnetic stimulation. We assumed that the nerve axon was located in an inhomogeneous conducting medium with two regions having different conductivities that simulate different tissue types. The distribution of induced electric fields was calculated with the finite element method. The nerve fiber was modeled after equivalent electrical circuits having active nodes of Ranvier. We observed the excitation threshold when the coil current waveforms and direction are changed with varying the electrical properties of the tissue. The simulation results show that the threshold is lower when biphasic waveforms are used and that the optimal current direction depends on tissue conductivity. The results also suggest that the nerve is excited even when the coil current flow is perpendicular to the axon in inhomogeneous conducting media. The results in this study give useful information to explain the experimental results in magnetic stimulation of the brain.
UR - http://www.scopus.com/inward/record.url?scp=65249144399&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=65249144399&partnerID=8YFLogxK
U2 - 10.1063/1.3068460
DO - 10.1063/1.3068460
M3 - Article
AN - SCOPUS:65249144399
VL - 105
JO - Journal of Applied Physics
JF - Journal of Applied Physics
SN - 0021-8979
IS - 7
M1 - 07B304
ER -