Can you sneeze while asleep? Whether you are curious about your own unconscious activities or if you wonder if that middle-of-the-night sneeze signals a good time to chat with your bed partner, you may want to know if you can sneeze while sleeping.
Sleep is not a uniform state. Instead, it represents a spectrum of different sleep stages. Throughout the night, it is normal to cycle through these sleep stages at regular intervals. The stages differ in the electrical activity of the brain, which correspond to varying levels of consciousness. Lighter stages of sleep correlate with more awareness of the sleep environment. This might extend to recognition of a stimulus to sneeze.
It would seem to be a reflexive action to sneeze. It is nearly impossible (and certainly uncomfortable) to stifle a poorly timed sneeze. In general, when you feel a tickle in your nose, your body responds by automatically sneezing to clear the nasal passage of the irritants. It seems logical that this reflex would still work in sleep.
Nevertheless, after years of watching people sleep in a sleep laboratory, I have never observed someone sneeze while sleeping. Perhaps this requires some level of consciousness on the part of the person sneezing that does not exist during any stage of sleep. In other words, if you aren’t awake enough to recognize that your nose is tickled, you can’t sneeze. This would imply a level of conscious control of sneezing, however, which does not seem to exist.
If there is a lack of sneezing during sleep, it may be due to a different phenomenon entirely. Normal body processes -- such as hunger, thirst, and the need to urinate or defecate -- are typically suppressed during sleep. It might be reasonable to conclude that sneezing is suppressed as well. How or why this occurs, or even what part of the brain might regulate its control, is not fully understood.
As we continue to learn about sleep and the brain, we may finally be able to definitively solve whether it is possible to sneeze while asleep and, if not, how this natural bodily function is suppressed.