Abstract
Magnetic stimulation has the drawback of poor focality compared with conventional electric stimulations, because of its dissipation of induced current. That makes it difficult to use magnetic stimulation for deep seated areas inside of a human body. This is a preliminary study for improving the focality of magnetic stimulation by using a conductive material, in this case a small copper ball, which can increase density of induced current inside of a volume conductor. We developed the system for measuring distribution of current induced in saline solution. The system consists of the stimulating coil, the saline solution chamber as a volume conductor, and the induced current probe. Measurements of the induced current are carried out with J without the copper ball. The stimulating coil was supplied with sine wave current by a function generator, and with mono-phasic pulse current by a magnetic stimulator (Dantec, MagPro). As a result, nearly double increase of density of induced current was shown in the vicinity of the copper ball.
