When you first perform a complex action, for instance learning to ballroom dance, you will have to dedicate your entire attention to making sure you move correctly. With practice, this complex behavior becomes almost automatic, and you can do it easily without having to think much about it. This phenomenon is called “muscle memory” because it almost seems like your muscles know what to do without your brain telling them.
“Muscle memory” is not an accurate term, because your ability to perform these actions automatically still comes from the brain, just a different part. With practice, the portion of your brain which controls your muscles is able to memorize the correct actions, so the part of your brain which deals with conscious thoughts does not have to occupy itself with the task. This way you are free to think about other things consciously, while your muscles are controlled by lower level parts of the brain.
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