# Injury reflexes

**URL:** <https://boards.straightdope.com/t/injury-reflexes/516891>\
**Category:** Factual Questions\
**Created:** [November 9, 2009, 11:38am UTC](https://boards.straightdope.com/t/injury-reflexes/516891 "2009-11-09T11:38:35Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Kobal2](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kobal2/32/20_2.png) [@Kobal2](https://boards.straightdope.com/u/Kobal2)\
**Post date:** [November 9, 2009, 11:38am UTC](https://boards.straightdope.com/t/injury-reflexes/516891/1 "2009-11-09T11:38:35Z")

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When we hurt our fingers, we immediately put them in our mouth. When another body part is hurt, we put our hands on it. Why is that ?

More interestingly, sometimes it even seems to work and reduce the pain. How come ? Is it a kind of placebo effect ? Is it that the nerves that are used to convey pain are also the ones that tell us about warmth or sense of touch, and the more immediate stimuli (i.e. something is touching your skin here !) overrides the other one (i.e. your body is damaged here, ease up) ?

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**Author:** ![Harmonious\_Discord](https://avatars.discourse-cdn.com/v4/letter/h/74df32/32.png) [@Harmonious\_Discord](https://boards.straightdope.com/u/Harmonious_Discord)\
**Post date:** [November 9, 2009, 11:48am UTC](https://boards.straightdope.com/t/injury-reflexes/516891/2 "2009-11-09T11:48:12Z")

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Pressure on the injury reduces the pain you feel.

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**Author:** ![yoyodyne](https://avatars.discourse-cdn.com/v4/letter/y/a9a28c/32.png) [@yoyodyne](https://boards.straightdope.com/u/yoyodyne)\
**Post date:** [November 9, 2009, 1:42pm UTC](https://boards.straightdope.com/t/injury-reflexes/516891/3 "2009-11-09T13:42:11Z")

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> [@Kobal2](#):
>
> Is it that the nerves that are used to convey pain are also the ones that tell us about warmth or sense of touch, and the more immediate stimuli (i.e. something is touching your skin here !) overrides the other one (i.e. your body is damaged here, ease up) ?

They’re not the same nerves, but the firing of non-pain nerves inhibits the pain nerves. That’s the [theory](http://en.wikipedia.org/wiki/Gate_control_theory_of_pain) anyway.

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**Author:** ![Philster](https://avatars.discourse-cdn.com/v4/letter/p/13edae/32.png) [@Philster](https://boards.straightdope.com/u/Philster)\
**Post date:** [November 10, 2009, 2:08pm UTC](https://boards.straightdope.com/t/injury-reflexes/516891/4 "2009-11-10T14:08:19Z")

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Rubbing the area can increase blood flow, too. It seems to smooth out the nerve firing. It is also beneficial to pull an injured body part close to your body, to protect it from further injury.

If my fingers get hurt, my reaction is to either grab them or place my hand under the upper part of my opposite arm, so that my fingers are between the side of my ribcage and my upper arm. This is a very good technique to protect the injury.

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