Tension-type headache and migraine causes

What are they?
Tension-type headache
Tension-type headache (TTH) is a head pain that occurs in frequent or infrequent shorter episodes (episodic*) or that is regularly or constantly present (chronic†).1 TTH are usually mild or moderate in intensity and may present as a “pressing” or “tightening” quality. It is usually not aggravated by physical activity.
Migraines
Migraines on the other hand, are severe and disabling attacks that reoccur over time and are often felt on one side of the head. It has a “pulsating” quality and is often associated with changes in light, sound and odour sensitivity. It is usually accompanied by nausea and neck stiffness. Patients will often experience seeing spots or stars during attacks and may feel fatigued or dizzy after.2,3
Pathophysiology, causes and triggers of tension-type headaches

Pathophysiology of tension-type headaches4
Unlike migraines, the mechanism of TTH is not clearly known. It may originate from tensed muscles especially around the neck area and can be stress-related.
Pathophysiology, causes and triggers of migraines

Pathophysiology of migraines6
Migraines are caused when the nerves and blood vessels around the trigeminal nerve (trigeminovascular system) located in the head are triggered to fire abnormally. When this happens, the trigeminal nerves produce and release substances called vasoactive neuropeptides, prostaglandins and inflammatory cytokines.
Upon release, these substances cause inflammation of the surrounding blood vessels, which in turn activates the pain receptors nearby (nociceptors). When nociceptors are activated, these sensory nerves send signals to parts of the brain responsible for producing the sensation of pain such as the thalamus and cerebral cortex.