Migraine auras are fairly common and said to happen in 20-30% of the migraine suffering population.
But auras and prodromes with phantom smells account for less than 1% of the migraine suffering population. (Study)
Some of the smells can be pleasant, and some can be painful to have to endure.
In this article, I’m going to be covering what phantom smells with headaches are and where they come from.
What are phantom smells?
Phantom smells, called phantosmia are a hallucination inside your olfactory or smelling system.
When the brain is affected by something like cortical spreading depression then wires can get crossed and signals can be sent through the part of the brain that processes smells.
This can results in the sensation as if we are inhaling an odor. But it does not actually exist, hence being called phantom.
These can also be created by brain tumors, epilepsy, temporal lobe seizures or head trauma so it is important to see a doctor if you experience phantom smells.
In migraine sufferers, phantom smells usually comes as part of the migraine aura or prodrome.
When the brain has been sufficiently damaged by stress then it will go through a cascade of responses creating cortical spreading depression and triggering migraine.
What is cortical spreading depression?
Cortical spreading depression has become the biggest buzz around migraines with aura in recent years.
It actually gives us a way to understand what is happening during a migraine aura and why.
I’ll keep it simple to make it understandable as the brain can get quite complex and there is a lot about cortical spreading depression we still don’t know.
Cortical spreading depression is a wave of electrical activity that goes throughout different parts of the brain depending on what is affected.
This wave is a series of “blackouts” where the electrical activity drops and “restarts.”
This event may be very damaging to the brain and is present in conditions like migraine and epilepsy.
To tie it to a metaphor, its like you are running your house on a gas generator.
But this gas generator is running out of fuel so the electricity coming out of it is uneven.
This causes the lights in your house to flicker on and off.
The fuel is running low and we need to fix it.
The brain protects you from this energy shortage by ramping up its protective mechanism we call migraine.
It uses the migraine to increase the delivery of nutrients and amplify its ability to repair damage and improve energy generation throughout the brain.
Just like all of our other pain reflexes, they are there to signal to us there is danger, make us stop doing what we are doing, and focus on what is going on.
To understand more about migraine auras see our article on the 3 truths of frequent ocular migraines with images here.
To learn more information than you’ve ever known about migraines, headaches and what to do about them, join the migraine professional community here.