Why do we instinctively put our fingers in our mouth after we’ve touched something hot?



Or after we’ve hurt it with blunt force trauma.

In: Biology

Moisture decreases the skin temperature once we remove the digit, which helps to construct the blood vessels reducing swelling?

Now that’s a guess but if the behavior sprung from an evolutionary survival instinct I’d think that’s the one.

It’s an instinctive response that takes advantage of a quirk of our biology. What it boils down to is the nerve fibers transmitting those pain signals are spooling up, intensifying the pain signal to your brain with each second after the initial injury. However, those nerves can only pass so many signals at once.

Stimulating the wounded area, like by sucking on the finger, interferes with this process. Those nerves sensing pain are suddenly having accommodate an additional stimulus that is non-painful. In effect, this leaves less bandwidth for the original pain signal to occupy, resulting in you feeling less pain.