PHYSIOLOGY AND GENETICS OF TENSION HEADACHE

Tension-type headache (TTH) is the most common type of primary headache. Also sometimes referred to as "muscle contraction headache," "stress headache," or "psychomyogenic headache, patients often report significant muscle tenderness with increasing headache frequency and intensity. TTH occurs repetitively and may be categorized into episodic TTH, with frequent and infrequent subtypes, and chronic TTH. The differentiating factor for these types is the frequency of headache episodes.