Why do people scratch their head when they don't know?

Answer:
It's a culturally learned sign for not knowing something.It could have just as easily been a raised middle finger.Imagine that. LOL.

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Lice

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Reflex or habit.

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nervous reaction

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Their brain itches. Just kidding. It's a cliche, like "laughing all the way to the bank." I've never seen anybody to either.

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The people that scratch there head when they dont know have the mokey scratch and it could get worse if they scratch there balls.So if you are a man or a very messed up girl don't scratch your balls because america has millions of ball scratchers and you could be next so stay away from monkeys and open flame thank you!

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What are people??

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to stimulate the brain?

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