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Why Can’t We Tickle Ourselves?

Friday, January 16, 2009 - 10:00 AM

Aristotle puzzled over the great mystery of why it’s impossible to tickle oneself. Turns out it’s quite simple, really. Here’s a brief explanation by British neuroscientist Sarah Blakemore that appeared in Scientific American:

“The answer lies at the back of the brain in an area called the cerebellum, which is involved in monitoring movements. Our studies at University College London have shown that the cerebellum can predict sensations when your own movement causes them but not when someone else does. When you try to tickle yourself, the cerebellum predicts the sensation and this prediction is used to cancel the response of other brain areas to the tickle.
Two brain regions are involved in processing how tickling feels. The somatosensory cortex processes touch and the anterior cingulate cortex processes pleasant information. We found that both these regions are less active during self-tickling than they are during tickling performed by someone else, which helps to explains why it doesn't feel tickly and pleasant when you tickle yourself. Further studies using robots showed that the presence of a small delay between your own movement and the resulting tickle can make the sensation feel tickly. Indeed, the longer the delay, the more tickly it feels.”

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Comments [25]

catherine stanis from indua

I dont feel tickled even wen someone else does it...then what does that mean ???

Apr. 16 2014 04:20 AM
Lucas Porter

OK, how does that explain masterbation

May. 08 2013 10:34 PM
kondor

I can tickle my belly and my ankles. And I am not ticklish in those two spots if others try to tickle me there. Interesting.

May. 08 2013 12:31 AM
solar

"Mystery solved! Haha, that silly Aristotle tried to actually think about these things. Now we have these fancy machines so we can unlock deep mysteries without thinking." Uh, no. Just observing that certain parts of the brain are active at certain time does not constitute understanding the mind. This is just a second observation of the fact that we can't tickle ourselves.

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Jul. 06 2010 07:18 AM
Liz Sales

Ah-ha! Science is posing answers to many philosophical questioned at a rate that now no philosophical conversation is meaningful without the inclusion of scientific ideas.

Oct. 11 2009 08:29 PM
roselyne

I'm always curious to know about how our whole body works... therefore amazed... it makes me aware of that we happily we need badly others...

Aug. 30 2009 10:48 AM
Lorenzo

This is interesting...would it go for pain as well?

for example (pardon me but i had to pick a very common example) if you pop yourself a pimple it's less painful than if an esthetics's does it...or is it only my impression?

i know my example can be a bit gross and i can understand any reaction to it..but i doubt many of you have given yourself a shot to be able to compare it with one given by a doctor...

what you guys think?

Apr. 03 2009 06:17 AM
Donovan

I too can tickle myself on the bottom of my feet, and it is REALLY ticklish. I find it a bit of a relief that others on here can also do this. My friends have always thought I was crazy...

Mar. 24 2009 04:24 PM
matt

here's an oddity, I am the ONLY person that can tickle me. Areas that are normally ticklish to myself are not ticklish when another person touches them.

Feb. 21 2009 06:29 AM
Ashlee

I can also tickle myself on the bottom of my feet and the roof of my mouth.

Feb. 09 2009 07:11 PM
Jason R

When I touch the bottom of my feet it tickles. I can't stand it when I get an itch on the soles of my feet. I'm stuck between the itching sensation and the agony of tickling my self when I scratch.

Feb. 05 2009 11:02 AM
Craig

I assume this is the same reason that the driver of a car never feels car sick by fast turning movments and yet most passengers do.

Jan. 31 2009 10:47 AM
Molly

To the masturbator, I think the article is really just meant to be a short summary hitting the broad strokes (pun intended) and I'm sure that all of your questions could be answered by maybe googling 'tickle study' or something. One thing I've always pondered that this seems to answer for me is why, as Eric mentioned, it feels so much better when someone else scratches my back, or, my favorite, plays with my hair or scalp. It's like night and day when I compare the euphoric sensation of someone else doing it vs. doing it myself (completely mundane). Just a thought. And Aaron, that's a really good point about the brains ability to "lessen the effects" by being able to predict them. This could be applied t many things. The surprise element enhances your reaction one way or the other, e.g. enjoying a back scratch, or freaking out over a tickle, by releasing endorphines or whatever chemical it is. You may be able to predict that someone is about to scratch your back, but you won't know exactly how they'll do it which is where the anticipation factor comes in. Interesting machine, the brain.

Jan. 30 2009 11:33 PM
Lora

So why are some people ticklish and some people not and some only sometimes ticklish or able to exert will over brain? What's going on there?

Jan. 30 2009 02:15 PM

I can't tickle myself, but I can definitely masturbate....

I am not sure that your theory is complete.

Also, the point about the robots is meaningless since you describe nothing about what the robots were doing, or were done to them, and why robot research on tickling is relevant to anything at all.

Do better please.

Jan. 25 2009 06:15 PM
jackson

a "pleasing sensation"?? obviously these researchers have never been tickled by someone they don't particularly like.

Jan. 25 2009 12:11 AM
Michael

I'm just not ticklish at all anymore. It's weird, one day as I was being tickled, I just thought,"why am I laughing? Why am I squirming?" Since then I've never been ticklish. It's kind of sad.

Jan. 24 2009 10:18 AM
Eric

I guess this also helps explain why it always feels better when someone else scratches my back!

Jan. 23 2009 07:40 PM
perri

Good call, Aaron. As I read the article I was thinking how I can't laugh if someone announces that they are going to tickle me. Guess the cerebellum predicts this sensation too.

Jan. 19 2009 06:12 PM
May

so I wonder what happens if I am tickling myself while another person tickles me? does that work to cancel the sensation? I will gave to try! hah!

Jan. 19 2009 02:22 AM
Aaron

It's strange that by predicting a sensation, the brain can lessen its effects. I tend to become more sensitive to that "tickly" feeling when I *know* that someone is about to tickle me in a particular area (In fact, I kind of go into ticklish fits, where the slightest touch sets off my ticklish reaction). But if this explanation behind this research is true, I wonder if the brain could lessen the effects of other sensations if it could predict them... Oh the possibilities!

Jan. 18 2009 12:40 PM
Chris

If it is true that the cerebellum monitors bodily movements and cancels out (part of) the associated sensation (viz., we feel the tickling finger, it just doesn't feel ticklish),then why are we able to scratch ourselves to relieve an itch?

Jan. 17 2009 03:41 AM
Ryan

I knew the first half of this for some time, the second half is a quite interesting addendum... The odd thing though, is I used to be massively ticklish, now I can basically switch it on and off (I can decide to be tickled or to ignore the sensation). And really, I can decide it when I do it myself though. I'm not sure that's accurate though, because I haven't had someone try to tickle me in quite a while, and might just be experiencing a different sensation...

Jan. 17 2009 12:28 AM
peterr

the roof of my mouth is really ticklish. why is it sooo sensitive up there??? p.s. i thought of this b4 i read the first comment so placebo is out:)

Jan. 16 2009 11:42 AM
kelly

I *can* tickle myself. On the roof of my mouth and on my belly but nowhere else which is normally ticklish.

Jan. 16 2009 10:59 AM

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