How do Gyral Orientation and White Matter Anisotropy Affect the Electric Field Induced by TMS?
نویسنده
چکیده
Ø Goal: Investigation of the underlying biophysical effects of transcranial magnetic stimulation (TMS). ØThe biophysics of transcranial magnetic stimulation (TMS) is not yet well understood. We characterize in detail the electric field induced in gray (GM) and white matter (WM), using a geometrically accurate model of an individual head combined with high-resolution diffusion weighted imaging (DWI). Use of finite element methods (FEM) allows determination of the impact of gyrus orientation and WM anisotropy on the field induced by a figure-8 coil. Questions: How does the modelling of white matter anisotropy influence the electric field distribution induced by TMS? Where does stimulation occur?
منابع مشابه
Physiological observations validate finite element models for estimating subject-specific electric field distributions induced by transcranial magnetic stimulation of the human motor cortex
Recent evidence indicates subject-specific gyral folding patterns and white matter anisotropy uniquely shape electric fields generated by TMS. Current methods for predicting the brain regions influenced by TMS involve projecting the TMS coil position or center of gravity onto realistic head models derived from structural and functional imaging data. Similarly, spherical models have been used to...
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