An electrode module is positioned inside an intracranial portion of a human head. Then, it captures brain images of the human head so multiples two dimensional (2D) cross-sectional images are obtained. The electrodes can be seen in one or more 2D cross-sectional images. A brain functional map adjusting portion is provided to obtain the 2D cross-sectional images and then to conduct a proportional deformation process for the images in the brain functional map database. By combining the processed images in the brain functional map database and the 2D cross-sectional images, multiple combined cross-sectional images can be obtained for display. So, the effects of intracranial electrodes are better than the traditional way. In addition, the brain structure information of a patient contains the precise positions of the electrodes and the corresponding brain functional areas.
