Micro-coil Design Influences the Spatial Extent of Responses to Intracortical Magnetic Stimulation
Magnetic stimulation from micro-coils has the potential to improve the spatial resolution of cortical stimulation by selectively activating pyramidal neurons while avoiding passing axons. Here, we explored how micro-coil design influences the effectiveness and selectivity with which neurons are activated. Computational modeling and physiological experiments revealed that the use of a sharp bend at the coil tip (V-shaped) enhanced coil selectivity; an additional bend provided even higher selectivity. The use of a second loop enhanced coil strength. Our results suggest that further optimization of coil design may help to enhance both the strength and selectivity of future coil designs.