It might have been the apple that put Snow White into her death-like sleep, but a similar thing happens to people every day – without an apple. It’s hard to tell what ails them, since there are two distinct conditions that share certain symptoms.
The conditions are catalepsy and cataplexy. For conditions that it is easy to confuse, you’d think they would have given them more distinct names, but I’m sure there is some Latin-root action going on there, so who am I to criticize?
According to medial dictionaries, catalepsy is “indefinitely prolonged maintenance of a fixed body posture, seen in severe cases of catatonic schizophrenia.” Cataplexy is “a condition marked by abrupt attacks of muscular weakness and hypotonia triggered by such emotional stimuli as mirth, anger, fear, etc. often associated with narcolepsy.
The symptoms that both conditions share is a loss of body control, the potential slowing down of body functions (such as breathing), and in both cases sufferers have been accidentally pronounced dead.
The differences are pretty different, however. People suffering from cataplexy will have muscle weakness, slurred speech, and their symptoms are almost always brought on by intense emotional stimuli. People suffering from catalepsy will go stiff and rigid, but their limbs will have what they call “waxy flexibility”, meaning that if you put their limb in a certain position it will stay that way – like you posed them. In very rare cases catalepsy can be brought on by strong emotion, but usually it is caused by an illness like Parkinson’s Disease or epilepsy, and some have been known to experience it in conjunction with cocaine withdrawl.
In both conditions, the sufferer can either be unconscious or totally aware – trapped in an unmoving body and unable to communicate their mental state. Catalepsy is sited as the condition Poe talks about in “Premature Burial” and “The Fall of the House of Usher,” as well as the state that Valentine Michael Smith reverts to in extreme emotional states in Robert Heinlein’s Stranger in a Strange Land.
At least for Smith, the state was voluntary, whereas 100% human-born and Earth raised folks have no control over their condition. Stories abound about people who have fallen into a cataplexic state while laughing at a funny movie, as well as people who have actually been taken to the morgue because their bodies were so still and their heart rate and breathing were so depressed.
Who knows what the creators of fairy tales had witnessed to give them the idea for Snow White to be in an apple-induced slumber – appearing dead to her seven friends, but it is possible that they had witnessed someone with cataplexy or catalepsy and put the intriguing condition into a story.