be relied on to distinguish essential language cortex. Rather, experiments that have tested for vital language sites are variable, and the exact role of a specific cortex area in a language task is difficult to judge. A further complication is that many patients who have undergone language mapping have epilepsy, which often alters the localization of cortical areas due to the neuroplastic response to cortical insult caused by the patient's seizures. Since the procedure is so invasive, cortical stimulation mapping for language organization is not done on healthy individuals. Additionally the distribution and abundance of specific task-related language sites have shown variation based on IQ and gender. Somatosensory mapping Somatosensory mapping involves measuring electrical responses on the surface of the brain as the result of the stimulation of peripheral nerves, such as mechanoreceptors that respond to pressure on the skin, and stimulating the brain directly to map sensory areas. Sensation has been tested in patients through the stimulation of the postcentral gyrus, with a drop in amplitude of sensory responses occurring towards the central sulcus. Clinical Applications Epilepsy CSM is an effective treatment for focal epilepsy and bilateral or multiple seizure foci. It is an effective treatment option when resective surgery to remove the affected area is not an option, generally seen with bilateral or multiple seizure foci. CSM is routinely utilized for patients with epilepsy in order to pin point the focal point of the seizures. It is used once there is a testable hypothesis regarding brain location for the epileptogenic zone, determined through a less invasive procedure, electroencephalography. Once the focal point of the seizures is determined, this information allows aids neurosurgeons with knowing what portions of the brain could potentially be resected without any negative post-operative neurological deficits. CSM will be considered for a patient with epilepsy when two conditions are met: the trial of anti-epileptic drugs has not controlled seizures and there is a likelihood that the surgery will benefit the patient. Due to the nature of the procedure, CSM is only utilized after noninvasive procedures have not been able to fully localize and treat the patient. The invasive electrodes are stereotaxically placed electrodes or a subdural strip or grid electrode. Utilizing the information obtained through CSM, limited resection of epileptogenic brain can be performed. For focal epilepsy, resective surgery is one of the mainstay treatment options for medication resistant epilepsy. Through the technique of CSM,