You may not know this, but Freddy Krueger could be real. And what I mean by that is it is a little known fact that the concept of A Nightmare on Elm Street is based (loosely) on real life cases of SUNDS, or sudden unexpected nocturnal death syndrome. On top of that, there are doctors out there who are very much like The Scarecrow, Dr. Jonathan Crane. And I mean eerily similar, like ‘putting you in a haunted house they designed with their extensive knowledge of fear in order to frighten and study you’ similar.

It’s no secret that we love being scared, why else would we keep going back to watch the latest Saw or Paranormal Activity? Around Halloween, haunted houses become our go-to fix for our amygdala, which in turn generates the secretion of hormones that influence fear and aggression. It is in just such a haunted house in Pittsburgh that Margee Kerr studies fear in the guests, collecting data on them before, during, and after their visit. A sociologist who teaches at the University of Pittsburgh, Kerr is working with neuroscientist Greg Siegle on a paper about the upside of fear.

“Going through a thrilling event, one where you know you’re safe, where you know you’re not going to get hurt, makes you feel good. It boosts your self-esteem, it makes you feel confident, it makes you feel accomplished” says Kerr. Sure, going through a haunted house, or jumping out of an airplane makes you feel accomplished in some way by the end, but fear is also designed to protect you, to send you running from dangers, to keep you wary and if necessary cause you to fight. It can also have a calming effect on certain people, turning off your complex cognitive behavior and causing you to focus on the experience and become more aware of your surroundings.

So fear can be useful and keep us safe and even make us feel good when we’ve gone through it, but what if you’re afraid of something you can’t avoid. What if you’re afraid of sleeping, much like the victims of Freddy Krueger’s nightmares. Hypnophobia, the fear of sleep is in itself a terrifying thought. For something so many of us take for granted, there are a few out there who suffer from this phobia. Some are afraid of dying in their sleep, which, for a group of Hmong men in the 80’s was all too real an occurrence. 117 of them, all but one healthy, seemed to die for no apparent reason, mostly in their sleep. It’s the kind of real life horror that can inspire the minds of Hollywood, and did. Wes Craven drew inspiration for his film from a series of newspaper articles about a group of Asian men who were dying in their sleep during nightmares.

Nightmares have long held a place in our fears in all cultures and throughout history. Sleep paralysis, pressing spirit attacks, are talked about in many cultures. It is known by many names, the Old Hag, succubus, and in Dutch it is the nachtmerrie or nightmare. Victims feel as though they are awake and cannot move and feel an overwhelming sense of dread and fear. This combination of cultural mythology and real life SUNDS deaths can really make one wonder, especially around this time of year. Shelley Adler, a professor at the University of California, San Francisco thinks the Hmong men were actually killed by their beliefs, not by a spirit, but by the belief that a spirit would come. It is the nocebo effect, the ability for belief to have a physical effect on the believer. These men, who had been uprooted from their homes were unable to fulfill their religious obligations according to their beliefs, and so the consequences that they believed would come, did. More information about Adler’s work and the Hmong case can be found in The Atlantic. But be careful what you believe, you wouldn’t want your dreams to get the better of you. One, two, Freddy’s coming for you….