system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do we only sneeze while we’re awake and never while we’re sleeping?

Is it involuntary, or is there a part of being conscious that tells us to sneeze because we are aware of what’s going to happen?
gpt
You know how REM sleep turns off your body so you don't flail about as you dream? 

It also shuts off the neurons that process stimulation from your nose. This means smells and irritants dont typically wake you up, or make you sneeze.