Does the brain feel pain?

It is likely that you once felt that your brain was going to “explode”. However, what we know today is that our entire body can hurt, except the brain, which is unable to feel it. We tell you why and how sensitivity works in these cases.

In this brief article we are going to answer the question ‘’Does the brain feel pain?’’ We will demonstrate whether the brain is capable of feeling pain and how it processes pain from other organs of the human body.

Does the brain feel pain?

No, the brain doesn’t feel pain. The brain processes pain signals from other parts of the body, but the human brain cannot feel pain, it does not have nerves capable of registering it. Nerve endings are usually found in the skin, and the brain has no skin, so it doesn’t feel pain.

Did you know that the brain cannot feel pain? The most fascinating organ of all, the one in charge of making our entire body feel bad, is incapable of feeling even a bit of pain. The explanation for this is that the brain does not have receptors for pain, the known nociceptors.

Harmful stimuli such as mechanical, thermal or chemical injuries that can cause tissue destruction (necrosis) and that also exceed a certain intensity threshold are detected by nerve endings called nociceptors.

Nociceptors send the alarm signal to the brain in tenths of a second through the spinal cord. So, the brain, the high command of our body, is the one that decides that pain occurs. And until, if necessary, the defensive mechanisms are put in place to face this aggression. These can be fever, inflammation…

We can find nociceptors in the skin, in the joints and in some internal organs, but curiously not in the brain. What a paradox!

But even though the brain cannot perceive pain, its surroundings, such as the meninges, nerve tissues, blood vessels, and neck muscles, can. Sometimes these tissues become inflamed, tense…

And even if, right off the bat, when your head hurts you have the feeling that your brain is going to explode, do not suffer, it is not your brain that is hurting you.

Why and how do we feel pain?

Why can something as annoying as pain be necessary? In an evolutionary sense, pain is extremely useful, because its main function is to alert us to the damage that is taking place in some part of the body, such as a burn on the skin or an infection in the throat.

This pain will immediately trigger responses that attempt to abort it. Thus, when we feel the heat of the flame, we reflect our hand away from the stove. In addition to provoking an immediate response, pain also triggers the initiation of conscious behaviors that mitigate it.

After suffering a severe sprain, for example, we all know that it is best to rest; our brain pushes us to stay still.

Pain is useful: it alerts us to the damage that is taking place in some part of the body

The tissue damage activates specialized molecular sensors, strategically placed on microscopic nerve endings that line the skin and viscera, such as the heart. These sensors discriminate between weak, harmless signals, and signals of damage.

Once activated, pain sensors generate electrical signals that travel rapidly along nerves made up of thousands of fine nerve fibers, all the way to the spinal cord where they connect to other neurons.

From here, the signal is distributed to many areas of the brain, where information is processed and the best response is evaluated. Using advanced imaging techniques, such as functional magnetic resonance imaging, it is possible to map the areas of the brain that are activated during pain.

These studies have made it possible to verify something that daily experience also reveals, that many areas of the brain participate in the perception and evaluation of pain, including areas closely related to emotions. This explains the subjective component associated with pain.

How to relieve pain?

While acute pain is clearly helpful, the situation changes when the pain is prolonged over time, as occurs in arthritis or during a herniated disc. This continuous pain can produce permanent modifications in the brain circuits that manage it.

Our brain is trapped in a kind of pathological mandala, in which painful stimuli repeatedly generate an increased sensation of pain, which can become unbearable.

This chronic pain is useless, aberrant, and must be studied and treated to try to break the vicious circle that amplifies it.

To relieve pain, doctors have many pharmacological tools such as anesthetics, which injected locally block the transmission of electrical impulses, so that the painful information does not reach our brain.

This is what happens, for example, in epidural anesthesia, used to control pain during labor. Substances such as cortisone, aspirin or acetaminophen relieve pain by inhibiting inflammation, a markedly potentiating factor in pain. Finally, morphine and its synthetic derivatives, which bind to neuronal receptors, block the transmission of pain impulses.

They are extremely effective drugs, although they must be used under the supervision of specialists due to their hypnotic effects and addictive potential.

How do we feel pain?

The brain plays a crucial role in the sensation of pain, since it is the one that produces it.

Among the mechanisms that make the brain generate this pain there is a key player: nociceptors.

These are nerve endings found in the skin, in the joints and in some internal organs.

They are pain receptors and are found in varying concentrations throughout the body.

Its function is to detect physical, chemical or thermal variations that could destroy our tissues.

Nociceptors have a certain threshold of resistance to pain, but when subjected to sufficiently strong stimuli, they send impulses to the spinal cord and from there travel to the brain.

At that point, the brain analyzes the data it receives and, mixing it with other factors (such as experience and learning), manages the signals to command a response or to ignore them.

That is to say: decide if it causes pain or not.

However, the brain itself cannot feel it because it simply lacks these receptors.

So how do you explain the headache?

The answer is that, although the brain cannot feel pain because it does not have receptors, the structures around it can, as Janet Bultitude, professor of cognitive and experimental psychology at the University of Bath, explains in an article for the scientific journal The Conversation.

These include, for example, the meninges, nerve tissues, blood vessels, and neck muscles.

Pressure or alterations in these structures activate pain receptors, which send signals to the brain, which is responsible for interpreting and experiencing all of our bodily sensations.

Bultitude explains it with two everyday examples.

The first is the headache that some people feel after eating ice cream or something very cold. In that case, the pain may be due to impaired blood flow in the veins between the back of the throat and the brain.

Regarding the headache that is associated with a hangover, it may be due to dehydration caused by alcohol consumption, which irritates the blood vessels in the head.

Why do we have a headache if the brain does not feel pain?

“Headaches are very interesting because we know very little about them. I have been working in this field for 30 years and I still learn something new every day.”

The phrase belongs to Anne MacGregor, a leading London-based medical researcher in the field of hormonal effects on migraine headaches.

And, according to the WHO, headaches have been underrated, underrecognized, and under-treated around the world.

Pain works as a warning system: it alerts us that we are doing something harmful and harmful, and waits for a reaction to solve the problem.

In that sense, the headache is no different from the others. It can be more or less acute, it can disappear with an analgesic or force us to stay in the dark in bed if it is a migraine, but the mechanism is the same.

However, although the brain is the organ that produces pain, it is unable to feel it.

It seems like a paradox, right?

So the brain can feel pain?

The brain, among many of its functions, is in charge of interpreting the signals from our body that inform us of pain, in this way we can set in motion mechanisms that help us relieve it (get away from what causes it, try to calm it through of a massage, take a drug …)

However, the brain itself as an organ does not have pain receptors. This makes possible brain surgeries in which the person is awake while the neurosurgeon intervenes to remove, for example, a tumor.

This allows you to proceed with the intervention with great care, making sure that areas such as language or memory are not damaged.

Even in recent years, brain interventions have been performed while awake patients played their favorite instruments (violin, clarinet …) in order not to damage any nerve endings and to keep intact the functions that could be affected.

FAQS: Does the brain feel pain?

What part of the brain feels pain?

The brain does not have pain receptors, called nociceptors. The brain plays a crucial role in the sensation of pain, since it is the one that produces it.

How do we get headaches if there are no pain receptors in the brain?

While the brain doesn’t feel pain directly, it is surrounded by membranes, blood vessels and muscles that do. Ordinary stress headaches are caused by the muscles in your scalp and spine.

Why does it feel like my brain hurts?

The muscles or blood vessels often become swollen, tense, or undergo other changes that stimulate or place pressure on the nerves around them. These nerves transmit signals to the brain about a blast of pain, and that is what triggers the headache.

Why does my head hurt everyday?

Some types of headaches, such as tension headaches, may be accompanied by pain or tightness in the neck. 

However, a sudden severe headache, along with a very stiff neck, fever, and / or sensitivity to light could be a sign of a serious infection that requires medical attention.

Can the brain repair itself?

When we suffer an injury, our skin and tissues regenerate. But the damage to the brain tends to be permanent, it has a limited regenerative capacity.

In this brief article we answered the question ‘’Does the brain feel pain?’’ We demonstrated whether the brain is capable of feeling pain and how it processes pain from other organs of the human body.

If you have any questions or comments please let us know!

References

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, 9(4), 463-484.

Melzack, R. (2001). Pain and the neuromatrix in the brain. Journal of dental education, 65(12), 1378-1382.