The signs of narcolepsy aren’t always obvious, despite how the condition is popularly portrayed. While the most evident symptom is daytime sleepiness, narcoleptic patients might also experience other symptoms. One of these is cataplexy — muscle weakness that is brief and usually triggered by emotional stimuli such as laughter, surprise or anger. Other symptoms include sleep paralysis, the temporary inability to speak or move while falling asleep or upon waking, and hypnogogic hallucinations, which are dream-like, sometimes terrifying, hallucinations that occur during the transition from wakefulness to sleep.
http://www.huffingtonpost.com/2014/07/30/sleepiness-narcolepsy_n_5610969.html
