Sneezing must be one of the strangest bodily occurrences that we experience as human beings. Sometimes, they come out of nowhere, at the strange whiff of a spicy scent or while walking along on a windy day. We feel the sharp intake of breath, and then the rapid exhalation of air from our nose and mouth. It’s usually accompanied by a loud sneezing noise (it comes in many shapes and sizes), often shocking the people around us.
Sneezing seems like an uncontrollable act by our bodies, happening at any time of the day if the conditions are right. But what about when we’re sleeping? Can this “uncontrollable” act happen when we’re drifting off in dream land?
The Science of the Sneeze
The fact that we sneeze is yet another piece of evidence that our body is always trying to protect itself. Sneezing is typically brought on when the respiratory epithelium of our nose is irritated in some way, whether that comes from pepper, airborne allergens, or anything else that might bother that sensitive membrane.
A sneeze is an involuntary reflex that comes from our cranial nerve in response to that membrane being irritated in some way. Essentially, our body is attempting to rid itself of foreign particles or material that could do harm to the body. When we’re ill with the flu or the common cold, our body tries to expel the viral infection that is irritating that membrane. If we accidentally inhale pepper, that strong stimulation almost immediately causes us to try and expel that material. There are a few other causes of sneezes too, such as light sensitivity, sexual arousal, a full stomach, or even pain in certain parts of the body (such as tweezing eyebrows or biting your tongue).
A sneeze is a combined effort of the parasympathetic, respiratory, and musculoskeletal system, expelling air (and irritants) from our bodies at nearly 100 mph. Due to the passive way that sneezing occurs, it would seem only natural that sneezing could occur while we sleep…. right?
The Slumbering Sneeze
When we lie down to sleep, due to the natural fluctuations of pressure and the force of gravity, those mucus membranes tend to swell up, which would actually make them more susceptible to irritation. However, most of the irritants that we encounter that make us sneeze happen because we are moving through the world, breathing through our nose, and stirring up particles. When we’re sleeping, there is a much smaller chance of this sort of artificial irritation happening.
Furthermore, in terms of the other causes of sneezing (particularly the stranger ones, like hunger and sexual arousal), most of these stimuli don’t occur while we’re sleeping in bed. At this point, many of you might be thinking back to the last time you were sick with the flu, when it seemed like you were sneezing and blowing your nose from morning ’til night. Why don’t those sneezes continue once you finally drop off to sleep?
Well, aside from the lack of movement and stimulation, the brain’s sleep patterns also help keep sneezing to a minimum. During our REM sleep, some of the chemical pathways and neurotransmitters stop functioning in the body. This means that even if there are viral pathogens irritating and inflaming that membrane in the nose, the brain simply isn’t getting the message to sneeze. This state is called REM atonia, and helps us extend our restful sleep cycle without constant interruption from rip-roaring sneezes.
There are limits to these preventative strategies, however, which is why so much cold medicine has sleep-inducing qualities that will help keep you under, even as the body tries to wake you up for a sneeze. In extreme irritant settings, such as sleeping on a pillow that a cat usually naps on, that dander can be enough to wake your body up to let loose a sneeze. This doesn’t happen very often, and requires quite a bit of unexpected stimulation.
To make a long story short, as long as you manage to get those eyes closed and lie still, take your cold medicine, and keep your pets and pepper spices out of the bedroom, you should be able to sleep soundly and sneeze-free!
- Sleep On, Sneeze Not – Indiana Public Media
- Do People Sneeze In Their Sleep Without Waking Up? – Mental Floss