
Study in mice explains how brain can turn pain signals up or down - laurex
https://www.nih.gov/news-events/news-releases/nih-study-mice-explains-how-brain-can-turn-pain-signals-or-down
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Funes-
>We know that pain is not static and that it can be modulated by several
factors. Early research showed that the central amygdala, long known for its
role in _processing fear_ , can dial up pain signals.

Interesting. A couple of days ago I was washing dishes and the water was too
hot, so I almost burnt my hand--or so I thought--by putting it directly under
the faucet by accident. Nonetheless, I started playing with it for a while:
how long could I keep it there? I realized that if I put my hand under it,
whenever I gave in to fear, the pain got unbearable, as if a switch had been
turned on.

I think that's why expert meditators can handle pain better. Also, meditation
and yoga reduce the right amygdala's volume [0], which processes fear and
negative emotions.

[0] [https://www.psypost.org/2019/08/meditation-and-yoga-
practice...](https://www.psypost.org/2019/08/meditation-and-yoga-practice-
linked-to-reduced-volume-in-brain-region-tied-to-negative-emotions-54273).

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ben_w
I have another anecdote about pain. A few years ago, cycling at night on the
then-under-construction path by the Cambridge Guided Busway, I bounced off an
invisible kerb and noticed the “pain” from the fall before I hit the ground,
when I was still at a ~45 degree angle; yet when I then picked myself up and
cycled on to the cinema I felt no pain — even though, when I checked myself at
the end of the film (one of the Hobbit films), I found I’d been bleeding
enough to make quite a mess.

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mikk14
It is pretty common under situation of physical effort not to feel pain, which
makes some sort of evolutionary sense.

Another anecdote: during last year's Tour de France, halfway climbing the Alpe
d'Huez (~13.8km at avg 8% slope, nothing to scoff at), Vincenzo Nibali got
knocked off his bike because it got hooked on a supporter's camera strap. He
got back on his bike and completed the rest of the climb faster than the top
contenders in front of him. When the doctors checked him, it turned out he had
a fractured vertebra. I suppose that must've hurt.

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kick
This is really cool!

 _The “switch” acts more like a “pain rheostat,” similar to a home thermostat
that modulates temperature — the pain rheostat reacts to pain signals to
modulate pain sensations. In the mice, researchers found that activity in
neurons that express protein kinase C-delta (CeA-PKCδ) turned up the pain
rheostat and demonstrated an increase in pain-related responses. Conversely,
researchers found that activity in neurons that express somatostatin (CeA-Som)
turned down the pain rheostat, inhibiting nociception or the chain of activity
in the nerves required to communicate pain._

 _During the experiments, researchers were able to take advantage of molecular
genetic approaches that allow them to fluorescently label and manipulate the
activity of these two central amygdala cell types. They found that when they
blocked CeA-PKCδ neurons, pain activity decreased. When researchers activated
CeA-Som neurons, they observed a marked analgesic response in mice._

Do these findings have any immediate practical benefit for humans?

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shakna
> Do these findings have any immediate practical benefit for humans?

Immediate? Probably not.

Practical? Probably yes.

There are quite a number of not-fully-understood chronic pain conditions out
there. This likely offers some alternative approaches that may lead to more
treatments, or even possible cures.

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noir_lord
Neuropathic pain is an utter bastard to treat.

There are medications that are effective - gabapentin and pregablin (for some
lucky people, me been one of them) but for others they aren't, Opiates don't
do much neither do OTC painkillers - There is some evidence that Tramadol can
help.

I'm glad we are continuing to make breakthroughs in the field even if it's a
decade or two before they may show up, pain is an incredibly useful
notification that something may be wrong except when the thing that is wrong
the notification system as a whole.

I can cycle 60 miles, work all day etc but some days if someone steps on my
foot I could drop them on the spot.

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tudorw
I'm interested in the role of genetics in pain experience, it's interesting to
see studies looking at the role of CYP2D6 in the amygdala, I look forward to
more research in this area.

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karlh
Just as interesting is the role of culture on pain experience. I believe I
recall a study some years ago that showed differences in pain experience
across different countries/cultures. Immigrants to a new culture continued to
show response patterns consistent with culture of origin. Their offspring
responded more like the new culture and more so over several generations. I
wish I could recall the research but it's been a while. Pain, especially
chronic pain (which is very different from acute pain) often presents very
similarly to an anxiety disorder.

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nobrains
Edit: Deleted

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ggggtez
Presumably: wait a few years for this to turn into a drug.

But more practically: talk to your doctor? Why would you ask a tech news site
for medical advice?

