do you know when...

people at work come up beside you and try to instruct you to open a certain folder or click on a specific link. Is it just me or does the mere presence of another person suddenly make me completely blind. It is like I stop reading and can't find anything. I don't know if it has to do with how I operate on computers, that I am visual and in motion and I have trouble converting language into the pictures I see and my usually automatic movements. Or maybe it is just my jobs which are so mindless that I lose brain cells each day I go to work. There is another possibility that this is not just me, and there is some unspoken phenomenon that makes a computer screen look like a camera lens covered in vaseline, as soon as a coworker steps by your desk and says "Can you open this..." or "Have you seen..." I am immediately braindead.