Dopers,
why do I stick my tongue out when I am concentrating?
I did not do this when I was young, now I’ve started as a man of 29 years. Why???
Spiffo
I’d like to know this myself as it has made me the center of ridicule by everyone in my family. The difference between you and I being that I’ve done it my whole life, from learning to tie my shoes to doing long form taxes.
I don’t know, but I’d like to know too.
I stick my tounge out the left corner of my mouth - always have. So does my mum. So does her mum. So do a lot of my uncles, aunts and cousins.
My sister bites her lip, just like my mum’s dad.
My brother sticks his tounge stright out, just like my dad.
My cousin sticks her tounge into the inside of her cheek, just like her grandmother.
I’d love to know why.
Hmmm… 
Way back when (back in '50s or so), my uncle bought a farm. Shortly afterwards, his tounge began to hurt. The reason remained a mystery until another relative pulled up to his farm while he was driving a mule to plow a field. Yep, he was concentrating on the work at hand and didn’t realize that he was giving his tounge a good sunburn every time he plowed.
The explanation I heard is that the parts of the brain that are responsible for delicate movements of the fingers are also in control of the tongue - I’m not sure how true this is.
Young babies put things into their mouths routinely; the tongue is very sensitive and it is possible to perceive texture and shape much more finely with the it than the fingers (that ulcer on the roof of your mouth feels the size of a grapefruit to your tongue) - adult tongue-sticking when concentrating on fine dexterity may be a hangover from this.
Mangetout, that may be so, but it doesn’t explain why some people (like me, for example) stick their tounge out when they’re just plain concentrating hard - I could be reading a book, or studying and out my tounge will pop - neither of those things require any finger movements.
I rarely stick my tongue out. I do tend to get a grimace-face when I’m doing something that requires lots of concentration, like playing a fast tune on my button accordion. I pull my lips in against my teeth and tighten my whole lower jaw.
I have to very consciously try NOT to do it when I’m playing music. It’s pretty ingrained in me though – I forget about my face for a minute and I’m back to grimacing with concentration again.
I guess there are no sports fans in your family, jarbaby?
But I’d think almost anyone from Chicago would have a hard time making fun of a tongue hanging out, given that it’s the classic image of Chicago’s most famous resident of the 90’s. He did pretty well with his tongue hanging out, as I recall.