Pain in the Brain: The Surprising Origins of Headaches 🧠
Exploring the Neurological Mechanisms and Hidden Triggers of Headaches (9min Read)
TL;DR Summary:
Headaches are common and can have different origins: muscular tension, vasodilation, neural inflammation, etc
Tension headaches are the most common, caused by stress and muscle tension
Migraines have a neural and vasodilation origin and affect women three times more than men
Cluster headaches are rare and occur more often in men with
Cluster headaches come from trigeminal nerve inflammation
Understanding the type of headache can lead to more effective treatment
Welcome Back!
According to the World Health Organization (WHO), almost half of all adults worldwide will experience a headache at least once a year.
And if that wasn’t bad enough already, migraine headaches are the third most prevalent illness in the world, affecting approximately 1 in 7 people globally.
So, what’s the neuroscience behind headaches? Where do they come from? How many different kinds are there? And most importantly, how do you relieve them?
Let’s find out! I hope that this post can act as your go-to guide for all things headaches and headache relief.
The 4 Origins of Headaches
Strangely enough, headaches don’t always originate in the brain or Nervous System.
The pain you feel from them does, but the actual reason why you’re experiencing one might not.
There are 4 ways headaches are thought to begin and understanding each can help you treat the type of headache that you have in a more tailored way.
Muscular
The first is muscular, specifically the muscles of your shoulders, neck, face, and skull.
You have way more muscles in these areas than you probably know about, check out the diagram below!
When these muscles are tight and constricted it can lead to tension headaches.
We’ll break these down more in a minute, before we do, why do these muscles get tight?
This group of muscles tends to hold a lot of stress, anxiety, and other pent-up emotions.
In today’s world, we aren’t generally taught how to release emotions, we’re taught to suppress them.
The more you store in your muscles psychologically, the tenser they become physiologically.
There is an exact neural mechanism that explains how this happens called Polyvagal Theory, but I don’t have time to dive all the way into that today.
The Meninges & Vasodilation
Vasodilation refers to the expansion of our blood vessels or the “widening” of them.
Vaso (Vessel) + Dilation (Widening/Expanding) = Vasodilation
In relation to headaches, this dilation is happening in the blood vessels around the brain, inside of something called the meninges.
I’ll spare you the intense neuroanatomy, and show you a picture instead.
The red & blue tubes you can see inside the subarachnoid space in the picture above are the blood vessels that expand when during vasodilation.
As you can also see, there’s not much space available, so when these vessels expand, they create pressure in this tight space.
This pressure triggers nociceptors or pain receptors inside the meninges to alert us with pain signals, hence the “ache” in headaches.
Neural Origins
The next origin we’ll cover is neural!
One of the best-studied nerves in relation to headaches is called the trigeminal nerve.
As you can see above, this nerve has 3 main branches, one to the eye/nose area, one to the lip area, and one to the jaw area.
The inflammation of this nerve can lead to cluster headaches, and lots of pain, especially behind the eyes.
Neural headaches come from the inside out, meaning it feels like they’re coming from inside your head and radiating pain outward.
Inflammation
Inflammation gets a lot of flack, and rightly so, but it’s important to remember that it can be good, and is an important immune response.
The issue is that it’s not a specific response, when it’s triggered, it sends out a huge signal that something is wrong.
Which then triggers increased blood flow, immune cells, etc to flood the area.
You’re probably not surprised that when this happens in the head, neck, or face area it can lead to headaches.
This is because inflammation can trigger the 3 origins we’ve already talked about.
The increased blood flow can trigger meningeal pain, and the inflammatory response can also cause our muscles to tense up, or aggravate nerves, like the trigeminal.
In this way, inflammation can be looked at as an underlying cause of these origins.
Pain in the Nervous System
While there are lots of different causes/origins of headaches, I’d like to be clear that the pain you are perceiving is coming from your Nervous System.
I mentioned them above, but a specific type of sensory neuron called a nociceptor is what causes us to feel pain!
We don’t have time to dive into each type of neuron in your Nervous System today, but these are important ones to mention when talking about this topic!
Types of Headaches
Understanding where your headache might be coming from is one of the quickest ways to understand which type of headache you may be struggling with.
Broadly, there are 3 common types of headaches. Tension headaches (most common), migraines, and cluster headaches.
In a recent Youtube video/Podcast, Dr. Andrew Huberman also covered hormonal headaches and traumatic brain injuries (TBI’s).
I won’t have time to dive super deep into these, so I suggest checking out his Podcast!
Tension Headaches
Tension-type headaches are the most common type of headache, affecting up to 78% of the general population at some point in their lives.
As I already alluded to, tension headaches generally originate from muscular tension.
This can come from sleep deprivation, excessive levels of stress, traumatic events, anxiety, high levels of stress or burnout, and sometimes even bacteria/viral infections.
A leading indicator of this kind of headache is jaw tightness/tension, meaning your jaw may pop often, or be sore constantly.
When one hits, here are some of the symptoms you might experience:
Dull, aching pain: Tension headaches often cause a constant, dull, aching pain that may be felt on both sides of the head, resembling a tight band or a vise-like grip.
Pressure on the forehead, temples, or back of the head: People with tension headaches often experience a sensation of pressure or tightness in the forehead, temples, or at the back of the head, near the base of the skull.
Scalp, neck, and shoulder muscle tenderness: Tension headaches can be accompanied by muscle tenderness or tightness in the scalp, neck, and shoulders. These muscles may feel tense or knotted, which can exacerbate the headache pain.
Sensitivity to light or sound: Although less common than in migraines, some people with tension headaches may experience mild sensitivity to light or sound, making bright lights or loud noises uncomfortable during a headache episode.
Duration: Tension headaches can last anywhere from 30 minutes to several days, with chronic tension headaches occurring more frequently or lasting longer than episodic tension headaches.
Migraine Headaches
Migraines alone account for more disability than all other neurological disorders combined…
As someone who experiences these myself, I can personally attest to this, they take me out for full days!
They are generally defined as disorders of recurring attacks of headaches, meaning they are a reoccurring issue for the people who experience them.
Something else to note is that women suffer from migraine headaches at a rate at 3x higher than men, and before you go there, the research hasn’t shown this to be hormonal in origin!
The other interesting thing about migraines is the “Aura” that often accompanies them.
Some people see this as a halo of light around their vision, sometimes a floater in their vision, or even the general sense that a migraine is coming on, even before any pain begins.
If it’s not obvious already, this is very different from tension headaches.
Migraines are one of the types of headaches that have a neural and vasodilation origin.
Meaning, they are thought to start deep in the Nervous System, possibly even the spinal cord, and come from the “inside, out.”
The vasodilation that comes with them also means there are some specific types of tools you can use to get relief from them, more on that in a moment!
The top 5 most common symptoms of a migraine headache include:
Throbbing or pulsating pain: This is often on one side of the head, but it can also occur on both sides.
Sensitivity to light and sound: They may be accompanied by a heightened sensitivity to light (photophobia) and sound (phonophobia). Bright lights or loud noises can exacerbate the pain, leading migraine sufferers to seek a dark, quiet environment for relief.
Nausea and vomiting: Migraine headaches frequently cause nausea, and in some cases, vomiting.
Visual disturbances (aura): Some people with migraines experience an aura before the headache begins. An aura is a set of visual disturbances that can include flashing lights, zigzag lines, blind spots, or shimmering spots in the visual field.
These typically last from 20 minutes to an hour and serve as a warning sign that a migraine is about to begin.
Intensified pain with physical activity: Migraine pain tends to worsen with physical activity, such as walking, climbing stairs, or even performing routine household chores. This increased pain can make it difficult for migraine sufferers to engage in daily activities during an attack.
I can personally attest to all of these things being true, it’s semi-traumatic to read the symptoms as I type them because of how much they suck when they come on!
As bad as migraine are, they’re nothing like a cluster headache… Let’s break them down.
Cluster Headaches
Cluster headaches are the rarest type of headache, but are extremely painful when they come on.
They have a neural & inflammatory origin, specifically the trigeminal nerve we talked about earlier.
When this nerve gets inflamed it cause the excruciating pain seen in cluster headaches.
This being said standard NSAIDs might not be the best solution for this kind of headache, you need something that can help with the neuroinflammation.
They are generally on one side of your face or the other, either behind the eye, or nose because of the way the trigeminal innervates these areas.
Men get this kind of headache 5x more than women, especially when they onset during sleep!
Here are some of the symptoms to watch out for:
Intense, burning, or piercing pain: The pain typically occurs on one side of the head, often around or behind the eye, as I mentioned above.
Eye redness and tearing: The affected eye may become red and watery during a cluster headache attack, as a result of the activation of the trigeminal-autonomic reflex, which controls facial sensations and the parasympathetic response.
Nasal congestion or runny nose: This happens on the side of the head where the pain is located, again, because of the trigeminal nerve!
Drooping eyelid and pupil constriction: The affected side of the face may display a drooping eyelid (ptosis) and a constricted pupil (miosis), both of which are associated with the activation of the parasympathetic nervous system during a cluster headache attack.
Short duration and recurrence: This kind of headache typically last between 15 minutes and 3 hours and occurs in “clusters”, meaning they happen frequently (up to several times a day) for a period of weeks or months, followed by a period of remission that can last months or even years.
Hormonal & TBI related Headaches
I don’t have time to dive too deeply into these in this post, but I intend to dive deeper in an upcoming blog.
For now, the basics are that when estrogen and progesterone are at their lowest, hormonal-type headaches can occur!
So, that means, for about the first week of the menstrual cycle many women are very prone to hormonal headaches.
This happens because of the way these hormones affect vasodilation!
Traumatic Brain Injuries (TBI) and the headaches that accompany them are also a topic for a whole blog, but for today’s purposes, let’s talk about the basics as well.
It probably doesn’t surprise you that hitting your head leads to headaches… Why though?
The main reason is swelling of the brain, and since there’s not much room in the skull like we talked about above, this can cause the pain that’s felt after TBI!
Next Week…
After realizing that I’m approaching 3000 words in this blog, I thought it would be best to split this topic in half!
So, next week, I will be covering solutions to these different types of headaches, and ways to get relief from them.
I hope you found today useful, and promise that learning where these things come from will be very useful to you as we dive deeper into how to solve these issues!
Until next time… Live Heroically 🧠
Supporting Research
Goadsby, P. J., Holland, P. R., Martins-Oliveira, M., Hoffmann, J., Schankin, C., & Akerman, S. (2017). Pathophysiology of Migraine: A Disorder of Sensory Processing. Physiological Reviews, 97(2), 553-622. https://doi.org/10.1152/physrev.00034.2015
Charles, A. (2018). The pathophysiology of migraine: implications for clinical management. The Lancet Neurology, 17(2), 174-182. https://doi.org/10.1016/S1474-4422(17)30435-0
Schulte, L. H., & May, A. (2016). The migraine generator revisited: continuous scanning of the migraine cycle over 30 days and three spontaneous attacks. Brain, 139(7), 1987-1993. https://doi.org/10.1093/brain/aww097
Olesen, J., & Ashina, M. (2011). Emerging migraine treatments and drug targets. Trends in Pharmacological Sciences, 32(6), 352-359. https://doi.org/10.1016/j.tips.2011.02.005
Goadsby, P. J., & Edvinsson, L. (1993). The trigeminovascular system and migraine: studies characterizing cerebrovascular and neuropeptide changes seen in humans and cats. Annals of Neurology, 33(1), 48-56. https://doi.org/10.1002/ana.410330109
Schwedt, T. J., Chong, C. D., Peplinski, J., Ross, K., & Berisha, V. (2017). Persistent post-traumatic headache vs. migraine: an MRI study demonstrating differences in brain structure. The Journal of Headache and Pain, 18(1), 87. https://doi.org/10.1186/s10194-017-0791-0
Burstein, R., Noseda, R., & Borsook, D. (2015). Migraine: multiple processes, complex pathophysiology. The Journal of Neuroscience, 35(17), 6619-6629. https://doi.org/10.1523/JNEUROSCI.0373-15.2015
Prevention of traumatic headache, dizziness and fatigue with creatine administration. A pilot study: https://bit.ly/3Y8lKLU
Long-chain omega-3 fatty acids and headache in the U.S. population: https://bit.ly/3X5lRXw
Dietary alteration of n-3 and n-6 fatty acids for headache reduction in adults with migraine: randomized controlled trial: https://bit.ly/3Y4SXaZ
Effect of omega-3 fatty acids on premenstrual syndrome: A systematic review and meta-analysis: https://bit.ly/40uX5Tu
Effect of Peppermint and Eucalyptus Oil Preparations on Neurophysiological and Experimental Algesimetric Headache Parameters: https://bit.ly/3wZegiu
Herbal treatments for migraine: A systematic review of randomized-controlled studies: https://bit.ly/40uXbuk