The cortical stimulator is a constant current, bi-phasic brain stimulator intended for cortical stimulation mapping to aid in cortical resection procedures.

Stimulation can be via a traditional hand-held electrode probe for intraoperative stimulation, or via intracranial electrodes. Using the touch-panel screen, the user can select any of up to 128 electrodes for delivery of stimulation pulses.

The cortical stimulator is available as the S12-X from Grass Technologies, and is FDA listed for clinical use.