Electrocorticography (ECoG) electrical activity from the cerebral cortex

I heard about this on public radio this morning. It sounds like a possible way to determine and map the extent of the damage.
This site has the broadcast:
http://minnesota.publicradio.org/features/npr.php?id=135598390
From Wikipedia:
Electrocorticography (ECoG) is the practice of using electrodes placed directly on the exposed surface of the brain to record electrical activity from the cerebral cortex. ECoG may be performed either in the operating room during surgery (intraoperative ECoG) or outside of surgery (extraoperative ECoG). Because a craniotomy (a surgical incision into the skull) is required to implant the electrode grid, ECoG is an invasive procedure. ECoG is currently considered to be the “gold standard” for defining epileptogenic zones in clinical practice.
Direct cortical electrical stimulation (DCES) is frequently performed in concurrence with ECoG recording for functional mapping of the cortex and identification of critical cortical structures.[7] When using a crown configuration, a handheld wand bipolar stimulator may be used at any location along the electrode array. However, when using a subdural strip, stimulation must be applied between pairs of adjacent electrodes due to the nonconductive material connecting the electrodes on the grid. Electrical stimulating currents applied to the cortex are relatively low, between 2 to 4 mA for somatosensory stimulation, and near 15 mA for cognitive stimulation. [7]
The functions most commonly mapped through DCES are primary motor, primary sensory, and language. The patient must be alert and interactive for mapping procedures, though patient involvement varies with each mapping procedure. Language mapping may involve naming, reading aloud, repetition, and oral comprehension; somatosensory mapping requires that the patient describe sensations experienced across the face and extremities as the surgeon stimulates different cortical regions. [7]