A model of magnetic stimulation of neocortical neurons

Transcranial magnetic stimulation (TMS) has been widely used in studies of human motor and cognitive functions as well as in clinical treatment. Bioph ysical mechanism underlying its effect is, however, largely unknown. Here, we develop a theory to calculate the effect of magnetic stimulation on arbi trary neuronal structure. Then, we employ a computer simulation which combi nes a realistic multicompartmental model of neocortical neurons and the cal culation of the induced electric field. The simulation shows that a single magnetic pulse applied to model cortical neurons can induce brief burst fir ing followed by a silent period of duration comparable to experimental data of TMS. Our simulation offers a new clue to understand physiology of TMS b y demonstrating that magnetic stimulation acts on biophysics of the dendrit es in neocortical neurons. (C) 2001 Elsevier Science B.V. All rights reserv ed.