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The Truth Is in There (the Brain, That Is): Sleep, Memory and Alien Abductions

Skye Harmony's picture

Up to 4 million Americans have experienced possible alien abductions, according to a 1992 Roper poll. (1) These experiences are marked by a myriad of bizarre sensations and, often, vague memories of nonhuman creatures. Common reported symptoms include a feeling of missing time, waking up unable to move, a strange sense of a presence, a feeling of flying or levitating, seeing balls of light, pressure on the chest, pain in the body, and seeing shadowy beings moving around the room (3, 4). Since ancient times, these strange events have been explained by cultures around the world as the influence or attack of supernatural beings ranging from witches to goblins to ghosts to demons. Only in modern times have people replaced these explanations with that of alien interference. Does modern science offer an alternate rationalization?

Many scientists think awareness during sleep paralysis provides an answer. Sleep paralysis, the immobility of the body due to post-synaptic inhibition of motoneurons in the pons (3), is a normal part of REM sleep and is thought to prevent people from acting out their dreams and causing harm to themselves or others. However, sometimes a person gains awareness while still paralyzed and navigating the delicate balance between sleep and wakefulness. This occurrence, known as awareness during sleep paralysis or ASP, can be terrifying, since it is physically impossible to move one’s body or speak, and it is often accompanied by strange hallucinations and sensations. Sleep specialists are not sure whether people are awake or asleep during ASP; there seems to be a gradient between being in a state of REM sleep and fully awake (4). ASP can last from seconds to minutes; common sensations are heaviness, anxiety, dread, increased heart rate, difficulty breathing, and the sense of a presence (3). It is thought that almost half of the world’s population has experienced ASP at least once; it occurs more often when REM cycles are disrupted by sleep deprivation or jetlag (4). Certain people are unlucky enough to suffer from this sleep disorder on a regular basis. It is possible that some of these people attribute their strange experiences to alien abductions.

A surprising number of supposed alien abductions, as many as 60%, occur during stages of sleep or waking (4). Even more suspicious is the fact that many reported symptoms of alien abductions are similar to those of ASP- in particular, paralysis; bodily pain or pressure; auditory, visual and olfactory hallucinations, often of intruders; a feeling of levitation or flying; and terror (4). Al Cheyne, a psychology professor, surveyed over 2000 people suffering from ASP and found that hundreds had indeed had experiences similar to alien abduction. Sleep disorders and alien abduction accounts both occur throughout someone’s lifetime and can have familial, possibly genetic, history (3, 4). Researcher Susan Clancy even found that people who have had abduction experiences suffer from ASP at a higher rate than those who have not (2). And Simon Sherwood, a sleep paralysis researcher, found that an ASP sufferer reported seeing aliens probing his brain after watching an alien movie (4). It is not so difficult to imagine someone trying to explain their ASP symptoms by attributing them to something they are more familiar with. Scientists believe that alien abductions occur commonly in popular media and therefore offer a plausible explanation to people who have bizarre symptoms and are trying to convince themselves they are not crazy.

ASP cannot explain all abduction experiences, however. Some happen in daylight; some happen in remote areas, where it’s unlikely that prior suggestion of aliens could have influenced the victims (4). Many scientists believe that false memories play a role in ostensible abductions. It has been proven possible to implant entire false episodes in someone’s memory; perhaps people who believe they have alien encounters are more susceptible to false memories (3). People seeking explanations for their bizarre experiences may end up going to counselors, including counselors who specialize in alien encounters (3). There they may undergo techniques such as hypnosis, guided imagery, regression and relaxation- which puts them in a suggestive state and causes them to let their imaginations run wild (2). Researcher Leonard Newman suggests that even daydreaming could create “pseudo-memories,” which are a patchwork of things people have heard or read about (4). The combination of the unexplained, bizarre events and the sufferer’s prior knowledge of traditional portrayals of aliens mix to construct false memories of abduction.

Indeed, the combination of ASP and false memories seems to account for supposed abductions. The similarity between the symptoms of ASP and abductions is too strong to be coincidental. People who do not know what is happening to them search for answers and seek out the familiar. Bizarre events lead many people to think of the supernatural, and maybe people have heard of abduction experiences and they compare their experiences to those. They may even go to therapists who hypnotize them. Both of these can lead to false memories; people reconstruct the event in their memory to fit what they think happened. False memories of aliens fit in well with the symptoms of ASP, especially the hallucinations and the sense that an unearthly being is in the room. Why would so many Americans attribute their symptoms to such an unproven source as alien encounters? Alien abductions are perhaps an unsettling answer, but traditional abduction accounts do fit with the symptoms and for many people, any explanation is better than none.

My own experiences with ASP are what motivated me to write this webpaper. One time I woke up paralyzed and could have sworn there was someone next to me in bed trying to harm me. Another time I woke up paralyzed and had auditory and visual hallucinations of shadowy figures moving around a table and whispering to each other. After this happened, I thought about how similar it sounded to abduction accounts but knew that it must be explainable by some kind of sleep abnormality. After reading about ASP I realized how perfectly it accounted for my symptoms, which some people might have attributed to alien interference. Having experienced some of the classic symptoms that alien abductions and ASP share, I feel strongly that many alleged abductions must actually be cases of ASP. I can easily imagine someone attributing their experiences to the paranormal if they did not have other information available.

ASP calls to mind several topics in neurobiology. First of all, it sheds light on the fact that we still don’t really have a definition of what it means to be asleep or awake. People undergoing ASP are consciously aware of their surroundings, but they experience visual hallucinations not unlike those of dreams, and they are still under the influence of sleep-specific movement inhibition. Second, ASP demonstrates a brain-body disconnect and raises questions about the role of the I-function. The body is essentially disconnected from the brain during REM sleep, and sometimes it takes a few minutes to reconnect (4). The I-function is not active during sleep, and it’s unclear whether ASP is considered sleep. However, if the brain tells the body to move during ASP, it cannot; therefore, while the brain does have conscious awareness, it seems that the I-function does not have total control.

As science comes up with alternate explanations for symptoms that used to be considered paranormal encounters, perhaps ASP will be found to explain other strange occurrences as well. Then again, some believers in the supernatural argue that aliens use sleep paralysis in their kidnappings in order to trick people. Who’s to say they’re not right?




1. Amos, Jonathan. “Alien ‘abductees’ show real symptoms.” BBC News 18 Feb 2003. <>

2. Cromie, William J. “Alien abduction claims explained.” Harvard University Gazette 22 Sept 2005. <>

3. Holden, Katharine J. and Christopher C. French. “Alien abduction experiences: Some clues from neuropsychology and neuropsychiatry.” Cognitive Neuropsychiatry 7.3 (2002). <>

4. Kristof, Nicholas D. “Alien Abduction? Science Calls It Sleep Paralysis.” New York Times 6 July 1999. <>


Steve's picture


Ok idk if this means anything. I’m not saying it does or doesn’t, just would like to know more. I had an experience where one night I woke up, or half woke up while sleeping on my stomach. I wasn’t able to move or turn over. As far as I remember I tried for a second and then just went back to sleep, woke up in the morning fine and didn’t think much of it. THEN a few weeks or so later I woke up one night (this time on my back) again unable to move. This time though I saw a circle of light about 2ft in diameter on the wall. It’s always weirded me out because it wasn’t like a light shining on the wall. It wasn’t bright or glowing. It looked like the space inside the circle was daylight, like I was looking at the wall through a paper towel roll or something. nothing on the wall or in the room was different just this spot on the wall. I guess the best way to explain it is if you took 2 photos of my bedroom wall, 1 at night and 1 in the day, cut a circle out of the night 1 and layed it on top of the day 1. That’s the way it looked.

Paul Grobstein's picture

Sleep paralysis: making sense of spirits and aliens?

Very interesting set of connections, suggesting that at different times people use different "stories" to make sense of their experiences (like we all fill in blind spots, see skulls or women looking in mirrors in ambiguous figures?). And raises some further interesting questions: are aliens really something people are "more familiar with"? Were spirits in fact something people were more familiar with? Maybe there is something other than "familiarity" that makes some stories more appealing than others?

For lots of peoples' experiences with /thoughts about sleep paralysis, see comments following Sleep Paralysis: Awake but Still Asleep.