Continuous dynamic mapping was found to be a feasible and ergonomic technique for localizing the exact site of the corticospinal tract (CST) and distance to the motor fibers. The acoustic feedback and the ability to stimulate the tissue continuously and exactly at the site of tissue removal improves the accuracy of mapping, especially at low (< 5 mA) stimulation intensities. This new technique may increase the safety of motor eloquent tumor surgery ¹⁾.