Most things that our bodies are made up to subconsciously do, with anxiety, become manual.  Things like breathing, walking, and simply looking around are broken down by our nervous minds into hundreds of racing thoughts.  We shake because we forget how to move properly; our minds demanding our attention on something as little as our trembling hands and lips.  We stutter because even our words are confused as they try to make their way from our brains to our tongues.  Our lungs stop taking in oxygen for moments at a time because we are so busy overthinking every little thing going on and our hearts beat faster because it is so much to handle at once.  So, if I stare off into space, do not respond right away, or stop talking mid-conversation, forgive me.  Sometimes, what seem like small functions to you, take up every bit of my attention.