Human mental bandwidth is finite. You’ve probably experienced this before (though maybe not in those terms): When you’re lost in concentration trying to solve a problem like a broken computer, you’re more likely to neglect other tasks, things like remembering to take the dog for a walk, or picking your kid up from school. This is why people who use cell phones behind the wheel actually perform worse as drivers. It’s why air traffic controllers focused on averting a mid-air collision are less likely to pay attention to other planes in the sky.
Via Ashish Umre