Narcoleptics have 90% less neuropeptide hypocretin
Curious what causes narcolepsy? Part of the disorder is due to narcoleptics having 90 percent fewer neurons containing the neuropeptide hypocretin than non-narcoleptics. Hypocretin is a chemical that keeps us awake and alert. It also elevates mood.
http://www.medicalnewstoday.com/releases/262889.php