abdominal migraine-a type of migraine that mostly affects young children and involves moderate to severe abdominal pain, with little or no headache.

arteriovenous malformation-a tangle of veins and arteries that can disrupt the normal flow of blood and is frequently associated with episodic headache.

aura-a warning of a migraine headache. Usually visual, it may appear as flashing lights, zigzag lines, or a temporary loss of vision, along with numbness or trouble speaking.

autonomic-occurring involuntary. Autonomic nervous system dysfunction is frequently associated with various types of migraine.

basilar-type migraine-a type of migraine, occurring primarily in young women, causing symptoms of abnormal brain stem functioning such as double vision, loss of peripheral vision, numbness, imbalance, or loss of consciousness.

benign intracranial hypertension-increased pressure within the brain that causes severe headaches. It can be caused by clotting in the major cerebral veins or from certain medications (including some antibiotics, human growth hormone replacement, and vitamin A and related compounds).

biofeedback-a process that increases an individual's voluntary control of physiologic states such as blood pressure and pain response.

cephalgia-head pain.

cervical arterial dissection-a tear in an artery wall that can lead to stroke or transient ischemic attacks.

cervicogenic headache-a type of headache caused by structural irregularities in either the neck or head.

chronic headache-headache that occurs 15 or more days a month over a 3-month period.

cluster headache-sudden, extremely painful headaches that occur in a closely grouped pattern several times a day and at the same times over a period of weeks.

computed tomography (CT)-a type of diagnostic imaging that uses X-rays and computer technology to produce two-dimensional images of organs, bones, and tissues.

cortical spreading depression-a wave of increased brain activity that slowly spreads from the back toward the front of the brain's surface and may be the basis for migraine aura.

epidural hematoma-bleeding between the brain's protective coating and the skull.

episodic-comes and goes.

ergot derivative drugs-drugs that bind to the neurotransmitter serotonin and help to decrease the transmission of pain messages along nerve fibers.

hemicrania continua-one-sided headaches that are chronic or continuous and respond to indomethacin treatment.

hemiplegic migraine-a type of migraine causing temporary paralysis on one side of the body.

hypnic headache-a rare form of headache that awakens individuals at night (also called "alarm-clock headache").

ice cream headache-a painful headache brought on by changes in blood flow that result from a sudden chilling of the roof of the mouth.

ischemic stroke-stroke caused by a clot that blocks blood flow to the brain.

medication overuse headache-caused by the overuse of drugs (more than 3 times weekly) to treat headache. While the medication may help to relieve the headaches temporarily, over time the underlying headache becomes worse and occurs more frequently, creating a vicious cycle of medication use and head pain. The pain improves when the medication is stopped.

meninges-the three layers of membrane that cover the brain and spinal cord.

menstrually-related migraine-a migraine that affects women around the time of their period.

migraine-headaches that are usually pulsing or throbbing and occur on one or both sides of the head. They are moderate to severe in intensity, associated with nausea, vomiting, sensitivity to light and noise, and worsen with routine physical activity.

new daily persistent headache-a type of treatment-resistant chronic headache marked by daily pain that can last for years.

neurotransmitters-chemicals in the brain that helps nerve cells communicate with each other.

nociceptors-nerve fiber endings that receive and transmit pain signals.

ophthalmoplegic migraine-an uncommon form of migraine featuring a droopy eyelid, large pupil, and double vision that may last for weeks after the headache pain is gone.

paroxysmal hemicrania-a rare form of headache that usually begins in adulthood and is marked by one-sided attacks that typically occur 5 to 40 times a day.

postdrome-the period following the headache.

premonitory-meaning before. Some individuals with migraine experience premonitory symptoms up to 24 hours prior to headache pain.

primary exertional headache-headache brought on by fits of coughing or sneezing, or by intense physical activity such as running or lifting.

primary headaches-headaches that occurs on their own with no detectable underlying cause, such as migraine, tension-type headache, and the trigeminal autonomic cephalgias.

primary stabbing headache-also called "ice pick headache" or "jabs and jolts" headache for its extremely intense pain that develops suddenly and generally lasts 1 to 10 seconds.

retinal migraine-a type of migraine that is characterized by attacks of visual loss or disturbances in one eye.

reversible vasoconstriction syndrome-a narrowing of the arteries in the brain that can cause sudden, "thunderclap" headache that may be brought on by bleeding in or around the brain.

secondary headaches-headaches that are caused by an underlying condition or disease.

serotonin-a neurotransmitter present throughout the body and brain that plays an important role in headache and migraine, mood disorders, regulating body temperature, sleep, vomiting, sexuality, and appetite.

status migrainosus-migraine lasting more than 72 hours.

subdural hematoma-bleeding between the brain and its protective membrane covering.

SUNCT (Short-lasting, Unilateral, Neuralgiform headache attacks with Conjunctival injection and Tearing)-a rare form of headache marked by brief recurrent bursts of moderate to severe burning, stabbing, or throbbing pain, usually on one side of the head and around the eye or temple, accompanied by symptoms including watery, reddish eyes, and runny nose.

tension-type headache-a primary headache that is band-like or squeezing and does not worsen with routine activity. It may be brought on by stress.

transient ischemic attack-a strokes that last only a few minutes but signals a subsequent and more severe stroke.

trigger-something that brings about a disease or condition.

triptans-a family of drugs used to treat migraines and cluster headaches by preventing or stopping nerve tissue inflammation and resulting changes in blood vessels.

vascular-refers to blood vessels or the flow of blood.

venous sinus thrombosis-a form of stroke caused by a clot that blocks blood flow in the brain's veins.