TMJ headaches can be classified as tension-type headaches and can be caused by a number of factors. One of the main factors that can cause headaches is constant muscle contraction which creates tension and reduces blood flow to the jaw area. This sends a signal to the body to send more blood to that area and as a result, vascular headaches occur due to the increased blood pressure to that part of the head. Jaw clenching and teeth grinding can also cause pain in the muscles in the head surrounding the jaw area causing a headache. Further studies also show that psychological stress can cause muscle spasms that can trigger TMJ headaches.