Are you ticklish? Why?

https://www.wonderopolis.org/wonder/why-are-your-feet-so-ticklish

“Along with your underarms, your feet are two of the most ticklish spots on your body. Scientists who have studied tickling will tell you that the areas of your body that are the most ticklish are usually also the most sensitive. These sensitive areas of your body act as a defense mechanism to help protect you from injury.

For example, your foot is very sensitive. This is because of the many nerves found in your foot. How many nerves? A lot! Scientists estimate there are almost 8,000 nerves located in your foot. Your foot also contains a high concentration of nerve endings very close to the skin, which are called Meissner's corpuscles.

Your foot's nerves also contain pain receptors in addition to touch receptors. Tickling the feet can affect both types of receptors, leading to greater sensitivity. This might also explain why some people do not like their feet being tickled!

Your foot helps to absorb the various pressures caused by standing, walking, and running. Your foot's nerves also help to protect your body from harmful impacts. These purposes are served well by the many nerves in your foot, which also makes them more ticklish!

Way back in 1897, psychologists G. Stanley Hall and Arthur Allin identified two different types of tickling. Light tickling, like the brush of a feather across the bottom of your foot, is called knismesis. Knismesis usually causes irritation instead of pleasure or laughter.

Harder tickling, such as when you use your fingers repeatedly to tickle someone's belly, is called gargalesis. Unlike knismesis, gargalesis often results in genuine laughter and can be enjoyable.

For years, scientists have wondered exactly why gargalesis tends to cause laughter. Some scientists believe tickling takes people back to when they were a kid and would engage in playful tickling behavior with their parents. No one knows for sure, though.

If you have ticklish feet, that's a good thing! Scientists believe non-ticklish feet can be a sign of problems with nerve receptors. Losing the ticklish sensation in your feet is also one of the symptoms of neuropathy, which is a degenerative nerve disease.”