Electroconvulsive therapy (ECT) is the most effective treatment for severe depressive disorder, and yet the mechanisms of its therapeutic effects remain largely unknown. A novel computational model is presented in this study to simulate and investigate direct cortical excitation caused by bitemporal electroconvulsive therapy (BT ECT), using a finite element model (FEM) of the human head. The skull was modeled with anisotropic conductivity, with an excitable ionic neural model incorporated into the brain based on the classic Hodgkin-Huxley formulation. Results suggested that this model is able to reproduce direct stimulation of the cortex during the application of ECT.