# What parts of the human body do not feel pain
**URL:** https://boards.straightdope.com/t/what-parts-of-the-human-body-do-not-feel-pain/715025
**Category:** Factual Questions
**Created:** [March 15, 2015, 2:13am UTC](https://boards.straightdope.com/t/what-parts-of-the-human-body-do-not-feel-pain/715025 "2015-03-15T02:13:58Z")
**Posts on this page:** 20
**Page:** 1
### Author:  [@Wesley\_Clark](https://boards.straightdope.com/u/Wesley_Clark)
#### Post date: [March 15, 2015, 2:13am UTC](https://boards.straightdope.com/t/what-parts-of-the-human-body-do-not-feel-pain/715025/1 "2015-03-15T02:13:58Z")
I guess it depends on how you define parts. I don’t consider products the body makes in this question but which are not attached to the body (saliva, urine, feces), it has to be things physically attached to the body.
Parts of the fingernails
Hair
tooth enamel and dentin (I think only the pulp feels pain)
brain
Anything else?
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### Author:  [@Ignotus](https://boards.straightdope.com/u/Ignotus)
#### Post date: [March 15, 2015, 2:38am UTC](https://boards.straightdope.com/t/what-parts-of-the-human-body-do-not-feel-pain/715025/2 "2015-03-15T02:38:31Z")
> [@](#):
>
> Parts of the fingernails
> Hair
> tooth enamel\* and dentin\* (I think only the pulp feels pain)
> brain
(My emphasis)
Never had a toothache, huh?
I think there’s a lot of inner stuff that doesn’t feel much. Liver, spleen, muscle tissue - you name it. Of course, if you try poking around, you may accidentally hit on a nerve…
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### Author:  [@bizzwire](https://boards.straightdope.com/u/bizzwire)
#### Post date: [March 15, 2015, 2:56am UTC](https://boards.straightdope.com/t/what-parts-of-the-human-body-do-not-feel-pain/715025/3 "2015-03-15T02:56:51Z")
As I understand it, the brain has no pain receptors. But I may be wrong.
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### Author:  [@Ignotus](https://boards.straightdope.com/u/Ignotus)
#### Post date: [March 15, 2015, 3:02am UTC](https://boards.straightdope.com/t/what-parts-of-the-human-body-do-not-feel-pain/715025/4 "2015-03-15T03:02:37Z")
> [@bizzwire](#):
>
> As I understand it, the brain has no pain receptors. But I may be wrong.
OP mentioned the brain, and I believe he is right.
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### Author:  [@bizzwire](https://boards.straightdope.com/u/bizzwire)
#### Post date: [March 15, 2015, 3:24am UTC](https://boards.straightdope.com/t/what-parts-of-the-human-body-do-not-feel-pain/715025/5 "2015-03-15T03:24:21Z")
> [@Ignotus](#):
>
> OP mentioned the brain, and I believe he is right.
Wow…I better lay off the NyQuil. :smack:
Carry on.
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### Author:  [@Velocity](https://boards.straightdope.com/u/Velocity)
#### Post date: [March 15, 2015, 3:34am UTC](https://boards.straightdope.com/t/what-parts-of-the-human-body-do-not-feel-pain/715025/6 "2015-03-15T03:34:38Z")
Wow, that’s hard to imagine that the brain would not feel pain. Interesting.
If a 6-inch steel nail suddenly appeared inside my brain, I imagine I’d be rolling on the floor in agony. Of course, I might be dead, but it’s still hard to fathom.
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### Author:  [@Senegoid](https://boards.straightdope.com/u/Senegoid)
#### Post date: [March 15, 2015, 4:22am UTC](https://boards.straightdope.com/t/what-parts-of-the-human-body-do-not-feel-pain/715025/7 "2015-03-15T04:22:15Z")
The walls of blood vessels are exquisitely sensitive to pain, in particular if those walls are stretched. There are blood vessels running through your head and brain. When they stretch, you can get gruesome headaches. Some people seem predisposed to have this happen a lot. That is what migraine headaches are.
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### Author:  [@Senegoid](https://boards.straightdope.com/u/Senegoid)
#### Post date: [March 15, 2015, 4:27am UTC](https://boards.straightdope.com/t/what-parts-of-the-human-body-do-not-feel-pain/715025/8 "2015-03-15T04:27:21Z")
I have often seen it claimed that the internal parts of the body have no pain receptors; you only feel pain at or near the surface. This is obviously bollocks.
Heart attacks (especially of the “Hollywood style”) are said to be exquisitely high on the pain meter. You can look up threads right on this board about kidney stones. Ever had gastritis or “heartburn” (esophageal acid reflux) or a tummy-ache or a wide-awake colonoscopy? Ever had a bone broken?
Our OP **Wesley Clark** asks a very reasonable question, and he seems to have a clue that the correct answer is: Very few.
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### Author:  [@dtilque](https://boards.straightdope.com/u/dtilque)
#### Post date: [March 15, 2015, 4:28am UTC](https://boards.straightdope.com/t/what-parts-of-the-human-body-do-not-feel-pain/715025/9 "2015-03-15T04:28:15Z")
> [@Velocity](#):
>
> Wow, that’s hard to imagine that the brain would not feel pain. Interesting.
When undergoing brain surgery, patients are usually only given topical anesthesia in the area of the incision. The patient is kept conscious and sometimes needs to give feedback to the surgeon on what kind of things they’re experiencing.
> [@](#):
>
> If a 6-inch steel nail suddenly appeared inside my brain, I imagine I’d be rolling on the floor in agony. Of course, I might be dead, but it’s still hard to fathom.
There’ve been a number of people who’ve caught a nail from a nail gun in the brain. Some weren’t even aware of it at the time. It’s not that it’s not serious, just that they can’t feel it.
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### Author:  [@rsa](https://boards.straightdope.com/u/rsa)
#### Post date: [March 15, 2015, 4:38am UTC](https://boards.straightdope.com/t/what-parts-of-the-human-body-do-not-feel-pain/715025/10 "2015-03-15T04:38:00Z")
> [@](#):
>
> **IGNOTUS**
> I think there’s a lot of inner stuff that doesn’t feel much. Liver, spleen, muscle tissue - you name it. Of course, if you try poking around, you may accidentally hit on a nerve…
Liver inflammation and an enlarged spleen can certainly cause pain, sometimes severe. Oviously there are a number of causes of muscle pain.
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### Author:  [@Velocity](https://boards.straightdope.com/u/Velocity)
#### Post date: [March 15, 2015, 4:54am UTC](https://boards.straightdope.com/t/what-parts-of-the-human-body-do-not-feel-pain/715025/11 "2015-03-15T04:54:41Z")
> [@dtilque](#):
>
> There’ve been a number of people who’ve caught a nail from a nail gun in the brain. Some weren’t even aware of it at the time. It’s not that it’s not serious, just that they can’t feel it.
But what about the punctured skin and membrane and skull bone that the nail passed through en route to the brain? Those parts would be hurting…?
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### Author:  [@Ignotus](https://boards.straightdope.com/u/Ignotus)
#### Post date: [March 15, 2015, 5:39am UTC](https://boards.straightdope.com/t/what-parts-of-the-human-body-do-not-feel-pain/715025/12 "2015-03-15T05:39:43Z")
> [@rsa](#):
>
> Liver inflammation and an enlarged spleen can certainly cause pain, sometimes severe. Oviously there are a number of causes of muscle pain.
See\*\* Senegoid’\*\*s explanation above (pressure in diluted blood vessels). I have (thank God!) never had a liver biopsy; but I’m told they only use a local anaestetic on the skin and then stick the needle right into your liver - without any significant pain.
I believe what the OP was asking is more like: Which parts of your body could you prick with a needle without feeling a thing?; rather than: which parts of your body can, if worse comes to worst, hurt like hell?
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### Author:  [@dtilque](https://boards.straightdope.com/u/dtilque)
#### Post date: [March 15, 2015, 9:04am UTC](https://boards.straightdope.com/t/what-parts-of-the-human-body-do-not-feel-pain/715025/13 "2015-03-15T09:04:25Z")
> [@Velocity](#):
>
> But what about the punctured skin and membrane and skull bone that the nail passed through en route to the brain? Those parts would be hurting…?
They probably think the nail just grazed their head. That would cause a wound similar to penetration.
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### Author:  [@Oglomott](https://boards.straightdope.com/u/Oglomott)
#### Post date: [March 15, 2015, 4:19pm UTC](https://boards.straightdope.com/t/what-parts-of-the-human-body-do-not-feel-pain/715025/14 "2015-03-15T16:19:27Z")
Pinch the skin on your elbow. No pain!
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### Author:  [@x-ray\_vision](https://boards.straightdope.com/u/x-ray_vision)
#### Post date: [March 15, 2015, 4:57pm UTC](https://boards.straightdope.com/t/what-parts-of-the-human-body-do-not-feel-pain/715025/15 "2015-03-15T16:57:22Z")
> [@Oglomott](#):
>
> Pinch the skin on your elbow. No pain!
That doesn’t mean that part of the body feels no pain, just that a pinch is not forceful enough to cause pain. Try using a pair of pliers (or dig your nails in).
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### Author:  [@Wesley\_Clark](https://boards.straightdope.com/u/Wesley_Clark)
#### Post date: [March 15, 2015, 5:07pm UTC](https://boards.straightdope.com/t/what-parts-of-the-human-body-do-not-feel-pain/715025/16 "2015-03-15T17:07:09Z")
> [@Oglomott](#):
>
> Pinch the skin on your elbow. No pain!
No, but dig your fingernails into it and see what happens.
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### Author:  [@rsat3acr](https://boards.straightdope.com/u/rsat3acr)
#### Post date: [March 15, 2015, 9:17pm UTC](https://boards.straightdope.com/t/what-parts-of-the-human-body-do-not-feel-pain/715025/17 "2015-03-15T21:17:41Z")
> [@Wesley\_Clark](#):
>
> I guess it depends on how you define parts. I don’t consider products the body makes in this question but which are not attached to the body (saliva, urine, feces), it has to be things physically attached to the body.
>
> Parts of the fingernails
> Hair
> tooth enamel and dentin (I think only the pulp feels pain)
> brain
>
> Anything else?
Up to a point on the dentin, there are tiny tubules that extend from the pulp space into the dentin. There are nerve fibers in these tubules. I assure you that considering this dentin feels pain.
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### Author:  [@iljitsch](https://boards.straightdope.com/u/iljitsch)
#### Post date: [March 15, 2015, 10:31pm UTC](https://boards.straightdope.com/t/what-parts-of-the-human-body-do-not-feel-pain/715025/18 "2015-03-15T22:31:08Z")
I read on Wikipedia the other day that bone doesn’t have pain receptors. However, the material covering it does, hence breaking bones is very painful.
When I had to inject anticoagulant into my legs sometimes this was rather painful and sometimes not at all. The former seemed to be correlated with bleeding. (Which is all kinds of fun when you’re on bloodthinners.) Eventually I learned to probe for non-painful sites.
And the tongue is certainly not on this list… I’m looking forward to being able to eat and brush my teeth without having to take painkillers first.
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### Author:  [@x-ray\_vision](https://boards.straightdope.com/u/x-ray_vision)
#### Post date: [March 15, 2015, 11:44pm UTC](https://boards.straightdope.com/t/what-parts-of-the-human-body-do-not-feel-pain/715025/19 "2015-03-15T23:44:06Z")
> [@iljitsch](#):
>
> I read on Wikipedia the other day that bone doesn’t have pain receptors. However, the material covering it does, hence breaking bones is very painful.
Was it the following?:
> [@](#):
>
> Although bone tissue itself contains no nociceptors, bone fracture is painful for several reasons:[2]
>
> ```
> Breaking in the continuity of the periosteum, with or without similar discontinuity in endosteum, as both contain multiple nociceptors.
> Edema of nearby soft tissues caused by bleeding of torn periosteal blood vessels evokes pressure pain.
> Muscle spasms trying to hold bone fragments in place
>
> ```
>
> Damage to adjacent structures such as nerves or vessels, spinal cord and nerve roots (for spine fractures), or cranial contents (for skull fractures) can cause other specific signs and symptoms.
> **[Bone fracture](https://en.wikipedia.org/wiki/Bone_fracture)**
>
> A bone fracture (abbreviated FRX or Fx, Fx, or #) is a medical condition in which there is a partial or complete break in the continuity of any bone in the body. In more severe cases, the bone may be broken into several fragments, known as a comminuted fracture. An open fracture (or compound fracture) is a bone fracture where the broken bone breaks through the skin. A bone fracture may be the result of high force impact or stress, or a minimal trauma injury as a result of certain medical co Altho...
The reference ([2]) used is no longer available:
> [@](#):
>
> We’re sorry, the page you’re looking for can’t be found.
I found the following which states nociceptors also exist deep within the bone:
> [@](#):
>
> Secondly, nociceptors have been found to project not only to the periosteum, but also deeply into the bone and bone marrow and are therefore in close proximity to both tumor cells and tumor-associated immune cells and stromal cells.
[http://www.hindawi.com/journals/jos/2012/758181/](http://www.hindawi.com/journals/jos/2012/758181/)
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### Author:  [@Terry\_Kennedy](https://boards.straightdope.com/u/Terry_Kennedy)
#### Post date: [March 16, 2015, 12:06am UTC](https://boards.straightdope.com/t/what-parts-of-the-human-body-do-not-feel-pain/715025/20 "2015-03-16T00:06:45Z")
> [@dtilque](#):
>
> There’ve been a number of people who’ve caught a nail from a nail gun in the brain. Some weren’t even aware of it at the time. It’s not that it’s not serious, just that they can’t feel it.
For an extreme case of “pointy object in brain”, I refer you to the case of [Phineas Gage](http://en.wikipedia.org/wiki/Phineas_Gage). If you have more than a passing interest in this sort of thing, I recommend reading [An Odd Kind of Fame: Stories of Phineas Gage](http://amazon.com/Odd-Kind-Fame-Stories-Phineas/dp/0262632594).
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