Language mapping by rTMS. This surface view of the human cortex shows the results of preoperative mapping of language eloquent areas by rTMS and an object naming task presented with the cortical parcellation system (CPS). Left column represents the first mapping, the right column outlines the mapping prior to the second surgery. Row 1–3 represent patient 1–3. For every single CPS region, a combined error rate for no responses and performance errors was defined as the ratio of induced no response and performance errors to the number of applied rTMS trains.