|MadSci Network: Neuroscience|
Thats a good question alexa. Well the fact is that humans cannot sneeze while asleep. Sneezing requires a reflex mechanism, wherein the sensory nerves in our upper respiratory tract, esp nostrils, are stimulated by some stimuli (mechanical or chemical or other)and these nerves then go to the CNS (i.e brain) and as a final process excite the nerves which supply muscles pf our respiration and the pharngeal region and the man sneezes thus. You must know that this reflex is a natural means to protect our sensitive upper respiratory tract from harmful influnces or, more appropriately, external influences, be it a solid or a gas or as a response to some infection. Now when the man sleeps, his brain is not working at its normal levels and so even though the man's nerves have some external factor acting upon them, no reflex is initiated and the man doesn't sneeze. You must also know that when the stimuli continues or crosses a particular level, it changes from an irritative agent to a source of maybe say pain and the the man can have a disturbed sleep; there is a threshold for every thing. Alexa, I think I've made it clear about the Mechanism and the reason that we don't sneeze when sleeping. If you have any further queries,feel free to ask me at my E_mail adress. Dr.Amit raina email@example.com
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