Have you ever pulled two all nighters in a row? If you have, then you know afterwards during the day. You keep drift off to sleep very easily and physically and mentally exhausted whole day. However, some people are suffering from narcolepsy must deal with this on a daily basis. They completely loss muscle tone and experience sudden sleep anywhere. . They don't know if what they experienced was a dream or if they actually experienced the situation. Imagine people falling asleep while driving or walking. Narcolepsy is a very common disorder; between 1 in 2000 people in the United States have this disease. You will be on the road with a narcoleptic any day.
How do you feel about driving on the same road with them?