Headache is defined as any pain related to the head or the face. Headache is a common and burdensome condition and is considered one of the major complaint in everyday life for many people. Most people will suffer from headaches at some point or another throughout their lives. Headaches come in a variety of forms, with tension headaches being the most prevalent. While the majority of headaches are not dangerous, some types may indicate a serious underlying condition. Primary headache disorders are headaches that are unrelated to an underlying medical condition and are categorized into 4 groups: migraine, tension-type headache, trigeminal autonomic cephalalgias, and other primary headache disorders .The central electrophysiological patterns in patients with primary headache disorders have been the subject of many studies. Despite the discrepancies between different research efforts, the overall picture strongly suggests that primary headache disorders can be the source of multiple patterns found in visual evoked potentials, Brainstem Auditory Evoked potentials and blink reflex . These patterns could be helpful in the diagnosis of different primary headache disorders as well as understanding the pathophysiology of various headache disorders.