Home > Migraines > Aura in Headaches: What Causes It?

Aura in Headaches: What Causes It?

By: Kathryn Senior PhD - Updated: 4 Jan 2011 | comments*Discuss
 
Aura Migraine Headache Causes Pain

Migraine with aura is one of the most common types of headache that are preceded by an aura, a collection of symptoms that occur just before the pain of the headache begins. A migraine aura is due to a complex set of events that happen in the brain; our understanding of exactly what causes an aura is at a relatively early stage.

What is a Migraine Aura?

An aura is a phase of a migraine headache that comes on within an hour or so of the headache pain itself. It may only last a few minutes in some people. Visual disturbances are the most likely form that the aura can take. People with migraine report seeing flashes of light, wavy lines, blurred vision, temporary blindness, spots of darkness in their vision and distorted images of the world. It has been suggested that Lewis Carroll, author of the book ‘Alice Through the Looking Glass’, was a migraine sufferer who experienced aura. His story of the different adventures of Alice may have been inspired by the images he saw in one of his migraine attacks.

In some people, a migraine aura includes more than just changes in their vision. It can also make their skin and limbs feel very strange, with patches of pins and needles, numbness, muscle weakness and trembling. Some people also feel very dizzy and unable to stand during the aura phase of their headache, while others experience ringing in the ears (tinnitus) and other hearing problems.

The Difference Between Aura and Prodomal Symptoms

A migraine headache, whether it is preceded by an aura or not, can also include a much longer pre-headache phase called a prodomal stage. This can come on 1-2 days before the migraine headache or the actual aura begins. The symptoms of the prodomal migraine stage are much less specific. People report feeling generally tired, unwell, and tend to yawn a lot and have a great deal of trouble concentrating. This should not be confused with an aura – this is specifically defined as being the stage immediately before the migraine itself.

What Causes a Migraine Aura?

We used to think that migraine was primarily caused by problems with blood vessels within the brain but researchers now think that abnormal electrical impulses in the nervous tissue are the root cause. These affect blood vessels, but the problem begins in the nervous system, not in the blood system.

A phenomenon called cortical spreading depression has been described and this is thought to be very important in the development of a migraine. This is caused by electrical activity at a much higher level than normal that spreads through the cortex of the brain, working over the cortex like a wave. As the wave of depolarisation spreads through the brain tissue, it passes through the visual centres in the brain, which may be why an aura includes so many symptoms that affect the vision. It also spreads through the motor areas, so affects the way people can move and produces the other sensations of numbness and tingling.

As the wave of electrical activity passes through the cortex, it induces changes in the blood vessels. As the wave first reaches blood vessels, they constrict and as it passes by they expand again, which can cause pain. The wave of activity also reduces the take up of oxygen by the tissues, causing a lack of oxygen in the brain tissue, which may also be responsible for some of the experiences of aura.

You might also like...
Share Your Story, Join the Discussion or Seek Advice..
Why not be the first to leave a comment for discussion, ask for advice or share your story...

If you'd like to ask a question one of our experts (workload permitting) or a helpful reader hopfully can help you... We also love comments and interesting stories

Title:
(never shown)
Firstname:
(never shown)
Surname:
(never shown)
Email:
(never shown)
Nickname:
(shown)
Comment:
Validate:
Enter word:
Topics
Latest Comments
  • Mumof3
    Re: Headache With Pins and Needles: Is This Serious?
    I have pins and needles beneath my feet, it has been there for three days now- and hasn't gone away.…
    25 March 2017
  • Ms. Haider
    Re: Headaches and Eyesight
    I wear soft contact lenses in the day time and take them out only when I'm ready to sleep. Even then if the contacts are out and I close…
    12 March 2017
  • Stassie
    Re: Migraine Classification
    My daughter has been diagnosed with migraine as she has most of the symptoms, so her neurologist said it was a classic one; He prescribed…
    10 March 2017
  • Alexandra
    Re: Headaches After Head Injuries
    I had hit ny head on a table and got a headache and it was getting worse so i went home, in the car i had passes out and my mom…
    10 March 2017
  • Alleycat
    Re: Headaches During The Night
    I have started walking with a headache about an hour after falling asleep.This happens at night or if I am sleeping during the day.…
    10 March 2017
  • Jad
    Re: Headaches and Iron Deficiency
    For the last year I've been getting shooting pains up and down the left side of my head which was diagnosed as trigeminal…
    8 March 2017
  • Stassie
    Re: Headaches Caused by Tensions and Stress
    Hi, My daughter, 16, has been diagnosed with having tension headaches, (via CAT scan and MRI) when she was 11. Since…
    7 March 2017
  • DUNK
    Re: Scalp Pain: What Causes It?
    I have suffered severe eye, scalp, jaw pain for 5 years. The pain has been so bad I have thought about suicide more than once. The…
    6 March 2017
  • "common-cold antenna
    Re: Scalp Pain: What Causes It?
    I've had this pain on my scalp in approximately the same area for a long time ( about 26yrs ). It happens just before I get a bout…
    26 February 2017
  • Julie
    Re: What is the Headache Impact Test?
    I wake up with severe headaches in the middle of the night. What do i do to stop it
    12 February 2017
Further Reading...
Our Most Popular...
Add to my Yahoo!
Add to Google
Stumble this
Add to Twitter
Add To Facebook
RSS feed
You should seek independent professional advice before acting upon any information on the HeadacheExpert website. Please read our Disclaimer.