Name: Why Some People Don’t Feel Pain
Uploaded: 2021-04-11T12:46:20.000Z
Duration: 3 min 59 s
Description: VoiceTubeの動画で発音を聞きながら英語表現を覚えよう！学べる英語：

Pain tells us when something is hot so we don't burn ourselves.

Pain tells us when we're hurt so we don't damage our bodies further.

As annoying and uncomfortable as it is, it actually saves us.

Some people are born with a genetic mutation that leaves them unable to feel pain.

There's actually a few mutations that lead to the condition called congenital insensitivity

According to a study published in the journal Nature Genetics, this mutation leads to a

Without functioning nerves, there's nothing to detect a painful experience.

Another mutation that causes people to not feel pain occurs in the SCN9A gene.

It causes disruptions not in the nerves, but in the way nerves talk to each other.

Nerve cells communicate by sodium ions, as these ions get passed through channels from

one nerve cell to the next, the pain signal travels from the injury site where it's felt,

But a mutation in the SCN9A gene stops these channels, called Nav1.7 channels, from forming.

Without these channels, pain messages can't be sent.

So scientists being scientists, made mice with this mutation in a study published in

And not surprisingly, the mice couldn't feel pain.

When their tails were exposed to extreme heat or cold, they showed no response.

But surprisingly, even though they felt no pain, their body tried to soothe it.

The mutated mice showed high levels of enkephalins, a type of opioid, the brain's natural painkiller

So even though these mice couldn't feel pain, their bodies recognized that pain and

So the researchers thought, hey, people who have less opioids in them tend to feel more

pain, I wonder what would happen if people who don't feel pain had less of these soothing

So they gave a woman who cannot feel pain naloxone, a medication typically used to treat

opioid drug overdose, and shot her with a heated laser.

Scientists said that the woman “quite enjoyed” the sensation.

So cool right? but uh, what good is it making people feel pain?

Whether we like it or not, pain evolved to save us.

Just take a look at our nerves that transmit pain.

Nociceptors sensory receptors are nerves whose only job is to transmit pain from the point

And they are fast, like pain can make it's way through these cells in 5–30 milliseconds

It's so quick and uncomfortable, because it gets you away from whatever is causing

Some evolutionary biologists think that a lesser warning, more of a “red flag” wouldn't

be enough for us to react so suddenly and strongly against a potential danger.

And we do know what happens when we don't have these kind of alarm bells in our body.

According to a study published in the Journal of Clinical Investigation, those who are born

without the ability to feel pain often suffer from infections they don't realize they

have, self injury, and they have shorter lives!

So the next time you stub your toe, don't yell out an expletive, yell out “thank you!”

Humans.. well we let each other know when we feel pain.

When other animals feel pain they yelp or cry out in some way.

But since crabs and other invertebrates can't… we kind of just assumed they don't feel

Well put down that order of crab legs, crabs do feel pain.

To find out more, check out this episode, right here