Simulation Study on Coil Design for Transcranial Magnetic Stimulation

The purpose of this study is to optimize the coil for transcranial magnetic stimulation (TMS). A novel multi-circle tangent coil (MTC) was designed, which consisted of five inner circular coils and one outer circular coil. These six circular coils were tangent to each other. The induced electric field and target area of MTC were investigated with both homogeneous phantom model and realistic human head model by numerical simulation. The results showed that MTC induced low electric field along its 4 surrounding inner coils thus weakened the stimulus effect on non-target areas. MTC not only takes the advantages of figure-8 coils with high focality, but also enables deep stimulation and multi-point stimulation at the same time. MTC is expected to have great potential in clinical application.