How many times have you rubbed your temples, gritted your teeth against the relentless pounding in your skull, and wondered, “Why, oh why, is my brain hurting so badly?” The fascinating truth is: your brain isn’t hurting at all. Confused? Let’s dive in and shed light on the conundrum of why our brain, the command center of pain, doesn’t actually feel any pain itself. But first, let’s address the big question at hand:
Headache or Brainache: What’s the Real Deal?
The reality is that the human brain, a marvel of nature composed of various tissues and cell types, lacks pain receptors. That’s right, despite being the central hub that registers pain from all over your body, the brain itself can’t sense pain. If a neurosurgeon could (hypothetically, of course!) open up your skull right now and give your brain a gentle prod, it wouldn’t hurt. The tricky bit, of course, would be getting through your cranium – now that, my friend, would smart quite a bit!
What’s a Nociceptor, and Why Doesn’t Your Brain Have One?
Throughout your body, there are special types of sensory receptors called nociceptors that alert the central nervous system to harmful stimuli. They detect changes like excessive heat, pressure, or even internal damage to your body. Ever swiftly yanked your hand back from a scorching stove? That’s your nociceptors doing their job, alerting your brain of danger and prompting your arm muscles to react.
However, your brain itself doesn’t have these nociceptors. That’s why brain surgery, even when the patient is awake, doesn’t cause any pain from prodding the brain itself.
If the Brain Can’t Feel Pain, Then Why Do We Get Headaches?
Good question! Here’s where it gets interesting. We often use the term “headache” as a catch-all for any discomfort in our head, face, or upper neck area. But not all headaches are created equal. Let’s look at some different types to help unravel this mystery.
Dehydration and Headaches
Ever woke up with a throbbing headache after a night of overindulgence? Dehydration could be the culprit. The exact mechanism is uncertain, but it’s believed that dehydration causes a movement of fluid out of the brain, leading to pressure on the meninges (membrane layers between the brain and the skull). Unlike the brain, the meninges have pain receptors, hence the headache.
Tension Headaches
If stress or sleep issues are constants in your life, chances are you’re no stranger to tension headaches. The discomfort stems from the muscles of your face and neck. Relieving this tension, perhaps through massage or over-the-counter painkillers, often helps.
Ice Cream Headaches
Ever experienced that sharp, sudden pain when you consume something cold too quickly? “Brain freeze,” as it’s affectionately called, is a result of blood vessels at the back of your throat constricting and then slowly dilating due to the cold. For some, this can trigger a pain response in the surrounding nerves.
Migraines and Cluster Headaches
Then, we have the more severe headaches, such as migraines and cluster headaches. Migraines are often characterized by intense pain, usually on one side of the head, accompanied by symptoms like nausea and light sensitivity.
Cluster headaches, on the other hand, are rare but cause sudden, excruciating pain on one side of the head. Regular pain medications often don’t help, but certain drugs and oxygen therapy can provide relief.
What’s important to understand is that these pains are not a result of the brain hurting, but rather various factors acting on the structures and nerves around it.
Now, the next time you experience a headache, remember: it’s not your brain that’s hurting, but a fascinating interplay of factors that create the sensation of pain. And as with any health concerns, always seek the advice of a health professional for any questions or symptoms.
Despite all we know about headaches, there are still many mysteries left to be unravelled. Yet, one thing is for sure: the human brain, a master of pain perception, doesn’t feel the pain itself. It’s one of the many paradoxes that make our bodies so incredibly interesting, wouldn’t you agree?
Further reading
May A, Goadsby PJ. The Trigeminovascular System in Humans: Pathophysiologic Implications for Primary Headache Syndromes of the Neural Influences on the Cerebral Circulation. Journal of Cerebral Blood Flow & Metabolism. 1999;19(2):115-127. Link
Goadsby, P. J., Lipton, R. B., & Ferrari, M. D. (2002). Migraine—current understanding and treatment. New England Journal of Medicine, 346(4), 257-270. Link
Tracey, I., & Mantyh, P. W. (2007). The cerebral signature for pain perception and its modulation. Neuron, 55(3), 377–391. https://doi.org/10.1016/j.neuron.2007.07.012
Apkarian, A. V., Bushnell, M. C., Treede, R. D., & Zubieta, J. K. (2005). Human brain mechanisms of pain perception and regulation in health and disease. European journal of pain (London, England), 9(4), 463–484. https://doi.org/10.1016/j.ejpain.2004.11.001
