Sudden cardiac death is the leading cause of mortality, accounting for approximately 50% of all cardiovascular deaths and 12% deaths. Although sudden deaths are commonly seen in patients with structural and ischemic heart diseases, some patients lack any evidence of coronary atherosclerosis or structural heart abnormalities. In these patients mental stress and abnormal neurological conditions can produce cardiovascular autonomic disturbances leading to life-threatening arrhythmias and sudden death. Emotional, physiological and physical stress is associated with increased rates of cerebrovascular events and sudden deaths. Human studies in healthy individuals showed lateralization of cardiovascular autonomic function exists in the forebrain, particularly the insular cortex.