I read once some intelligent people still have some process cycles left when working out code and it's uneasing to them so their brains automatically adds anoth

I read once some intelligent people still have some process cycles left when working out code and it's uneasing to them so their brains automatically adds another soothing activities to fill the void. For one of my coworker it was either whistling, feet tapping or pen clicking. To the point that another coworker regularly stand up from his chair, walked to him and put a spongy stress ball in his hands. Without saying a word, was funny the first time :D.