Calculating the Current Density and Electric Field in Human Head by Multichannel Transcranial Magnetic Stimulation

In this paper, we present a designed multichannel transcranial magnetic stimulation (mTMS) system with 40 small coils. The induced current density and electric field in realistic human head model by mTMS were calculated by impedance method and the results were compared with figure-of-eight coil. The dependence of stimulation focality on the coil current direction was investigated. Properly adjusting the input current phases can improve the magnitude of the induced fields in the brain.