Alien Abduction or Sleep Paralysis?

 © Kathleen Marden


     I have personally been embroiled in the UFO abduction debate for half a century and professionally involved for the past thirty three years. As the niece of Betty and Barney Hill, who had the first scientifically investigated case of UFO abduction  in the United States, I find this unsolved mystery fascinating.

     I have had my own mysterious contact events. For example, on February 22, 1966, I observed an unconventional flying object hovering less than 1000 feet above me and five other witnesses, including my aunt Betty. I have observed additional anomalies that have been linked, in the tree major studies I have worked on, to alien abduction phenomena. I have, however, never experienced sleep paralysis. However, I have been fully awake when intruders entered my home. Then I was paralyzed. But this is not sleep paralysis. 

     Several skeptical scientists have suggested that sleep paralysis is the best explanation for ET contact in one's bedroom. Nearly all abductees/experiencers of contact with non-humans believe they have been paralyzed to facilitate safe transport into an unearthly environment. Many were initially taken when they were wide awake, from their car, campsite, forest, or field, after having a close encounter with an unconventional flying object and/or observing non-human entities. The majority have experienced "missing time." They are convinced that their subsequent visitations in their homes are not sleep related anomalies.

     Some have no memory of being taken from an outdoor environment. They have only vivid memories of being taken from their beds during the night by humanoid figures and later returned with new, unexplained marks on their bodies. Others might suspect they have been experienced ET contact because they have observed strange lights in their bedrooms at night, or observed the disembodied face of an alien figure above their bed.

     Skeptics remind us that in the absence of substantial evidence, we cannot accept anecdotal abduction accounts as real. Our perception of the events that occur during the night, while we are sleeping or partially awake, could possibly be distorted by our sleeping minds. REM (rapid eye movement) sleep, visual imagery, and sleep hallucinations can be confusing. But rigid skeptics will not accept physical evidence associated with ET contact memories and "missing time."

     One thing is clear. All of us experience paralysis as a function of REM sleep. More dreaming occurs during REM sleep than in another stage of sleep. The paralysis prevents us from acting out our dreams and harming ourselves or others. It is most frequently reported to occur when we are falling asleep. But it can also occur upon waking. Some people have a sleep disorder that that interferes with normal REM sleep, causing them to act out their dreams. This condition requires medical treatment because REM sleep disordered people have injured themselves or family members while acting out their dreams in REM sleep.

     Sleep paralysis is related to REM but is a different entity. It can occur just before falling asleep or waking up. You will have conscious awareness of your surroundings but not be able to move anything except your eyes. You might observe shadowy figures in your bedroom and your heart might pound, as a sense of fear jars you into wakefulness. About 30-40% of those queried by sleep study scientists report that they have experienced sleep paralysis. It is simply a sign that their bodies are not moving smoothly through the stages from sleep to wakefulness.

     People with narcolepsy, a condition characterized by excessive daytime sleepiness and REM activity within ten minutes of falling asleep, are more likely to experience sleep paralysis accompanied by hypnagogic or hypnopompic (H/H) hallucinations than the general population. Sleep paralysis alone is characteristically different than the colorful imagery described by people who have experienced H/H hallucinations.

     There is conflicting information about H/H hallucinations and I have not been able to find conclusive answers regarding its prevalence among human populations. H/H hallucinations can last up to several minutes and affects an estimated 5-12% of the normal population. However, David J. Hufford wrote in The Terror That Comes in the Night, that 50% or more of Yasuo Hishikawa’s narcoleptic subjects reported that they had experienced H/H hallucinations. This indicates that people with narcolepsy have a higher rate of sleep hallucinations than the general population. 

     Hypnagogic (between waking and sleeping) and hypnopompic (between sleeping and waking)  hallucinations occur when factors such as stress, extreme fatigue, medications, and mental illness cause the part of the brain that distinguishes between conscious perceptions and internally generated perceptions to misfire. This results in internally generated visions, sounds, feelings, smells or tastes. H/H hallucination experiencers often see colored geometric shapes or parts of objects. Others might observe the full image of a person, monster or animal. Sometimes lines or the outlines of figures are observed. Sensations of floating or flying are common, along with hallucinated buzzing sounds. H/H hallucinations can be frightening. The hallucinations can last from seconds to minutes and are usually accompanied by a brief period of sleep paralysis. They are experienced as being as real as real.

     I once personally experienced a hypnopompic hallucination, without sleep paralysis. My husband and I were sleeping soundly, in the middle of the night, when the telephone jarred me into partial wakefulness. I didn’t answer the phone because I “saw” my husband walk toward it. Even though the room was dark I "saw" his brightly colored red and black plaid flannel shirt. The colors seemed brighter than they were when I was fully awake in natural sunlight. I was perplexed because the phone continued to ring even though I “saw” my husband lift the receiver from the cradle. Almost immediately I was startled by the awareness of his presence in the bed next to me. My hallucination vanished and I answered the phone. It is the only hypnopompic hallucination that I have ever had, but as a lifelong student of human cognition, I found it interesting and informative.

     Some sleep scientists contend that an experiencer’s perception of alien abduction while sleeping or awake in bed is most likely attributable to sleep paralysis, perhaps with hypnopompic hallucinations. They suspect that extraterrestrial entities are generated in hypnagogic and hypnopompic sleep states. Sleep hallucinations might be related to dreams because they are more elaborate and enduring than sleep paralysis alone. Hypothetically, we might be sleeping and perhaps dreaming about alien entities. When we start to move out of REM sleep, we might experience a hypnopompic hallucination and “see” nonhuman entities in our bedroom. We might even perceive this as a real event. However, after a few seconds we are fully awake with memories of the onset of an abduction or contact experience. 

     If we experience a combination of sleep paralysis and H/H hallucinations, we will suffer intense fear and wake up paralyzed, unable to move anything except our eyes. We might observe shadowy figures standing beside our beds or hovering overhead. If we attempt to cry out we find that we cannot utter more than a nondescript sound. We’re locked inside paralyzed bodies, unable to speak or move anything, except for our eyes. Our hearts pound and we strain to breathe as if there is a weight upon our chests. We are acutely aware of our surroundings. Shadows transform into frightening shadowy images and sounds intensify. We struggle to break free from our dreadful predicament and within seconds we are fully awake.

     I have never met an abductee/experiencer who believes that their ET contact experience was sleep related. However, I have spoken with several sleep paralysis and H/H hallucination experiencers. They have described memories that are different than what experiencers recall. Additionally, it is important to remember that real ET contact events leave some conscious recall and physical evidence. Experiencers need only to learn how to collect and document it. (Read my book "Extra Terrestrial Contact: What to do When You've Been Abducted")

     Many experiencers have described distinctly different demarcations between sleep paralysis, H/H hallucinations, and real abduction experiences. They insist  they were fully awake at the onset of an alien abduction or visitation. They might even have received a telepathic message or other indicators signalling an impending visitation. They did not wake up paralyzed. This has occurred only after they cried out or attempted to defend themselves. Some might even remember being transported through solid objects, such as a wall, roof or window. Most have observed non-human entities and might even retain a complex memory of being examined on the craft and/or given instructions and education. They are later returned to their beds.

     Prior to the onset of their contact events some witnesses report glancing nervously at their alarm clocks, unable to sleep due to their anxiety related to an impending abduction. Having noted the time on their alarm clocks prior to and after their experience, they can think of no prosaic explanation for the lost time. Sometimes bed partners and family members sleeping in the house recall identical experiences on the same night. Skeptics should ask themselves if they and their bed partners have experienced simultaneous sleep paralysis and H/H hallucinations.  

     MUFON’s Experiencer Research Team (ERT) has completed a comprehensive multi-year (2015-2018) study on UFO abduction and contact experiencers. It was a two-phase research study designed to obtain general statistical data, and to compare the experiences of groups of experiencers who participated in the phase 2 American Personality Inventory, evaluated by research psychologist Dr. Don C. Donderi. 

     ERT members Craig Lang, MS (1956-2018), Michael Austin Melton, PhD, Denise Stoner, and I (Kathleen Marden) developed 118 questions for the “Experiencer Survey.” Our objective was to identify a variety of characteristics that experiencers share and to collect statistical data that would be of value to MUFON investigators, researchers, and experiencers alike. Our questions were straightforward and pertained to the abduction/contact experience, based upon our investigative findings, the historical findings of other investigators, the psychological research findings in a variety of academic studies, and the postulates offered by prominent skeptics. The survey questions pertained to demographics, family structure, generational contact, religious/spiritual beliefs, emotional impact, medical impact, psychic and paranormal phenomena, perceived treatment by NHI (nonhuman intelligence or intelligent) entities, description of NHI, the contact experience, MILABS, and messages from NHI. 

     The greatest problem with a survey of this type is the inability to measure the psychological functioning of its participants and the veracity of the statistical data. Given the opportunity for hoaxers (fakers) and delusional people to participate in the study, we developed trick questions to identify and exclude this category of participant. The questions were carefully worded and presented to prevent false positive or false negative responses. All incomplete questionnaires and those identified as completed by fakers were eliminated.

     MUFON advertised the study in the MUFON UFO Journal. I placed it on my Facebook page, my website, and on two or three of my radio interviews. MUFON’s ERT encouraged the experiencers they counseled to complete the survey if they met the criteria for participation. We intentionally did not elicit participation from contactees who practiced astral travel, conscious contact with non-physical entities, remote viewing, and shamanic drug induced contact. 

     Phase 2 of our study was completed by Dr. Don C. Donderi, a retired research psychologist from McGill University. He administered the “American Personality Inventory” (API) to 188 survey participants that agreed to take part in the next phase of our survey. The API was developed by Ted Davis, a clinical social worker, and Budd Hopkins (1931-2011), a distinguished Abstract Expressionist artist and UFO abduction researcher from New York City, as an indicator of UFO Abduction Syndrome. Davis and Hopkins used the well-known psychological measure the Minnesota Multiphasic Personality Inventory, as a model for the API. Dr. Donderi collaborated with them by enlisting the assistance of students at McGill University as the control groups for its evaluation and standardization of the statistical portion of the test. 

     In 1991, researchers Budd Hopkins and David Jacobs, PhD, Associate Professor of History at Temple University (now retired), cooperated on a Roper poll survey to obtain statistical data on the percentage of Americans that had been abducted by aliens. Five marker questions were built into the survey. The first question pertained to waking up paralyzed with the sense of a strange person or presence or something else in the room. This question was criticized by social researchers because it was vague and could be an indicator of sleep paralysis. We wanted to separate sleep paralysis from the paralysis that occurs when experiencers are awake, observe a NHI presence in the room, and become paralyzed. 

     We posed two questions pertaining to sleep paralysis in an attempt to separate possible sleep paralysis and sleep hallucinations from

 conscious recall of contact in a wakeful state. The first question we asked is as follows: 

Have you awakened unable to move your body or cry out? 

(Survey Takers N: 510)

     Among the 510 survey takers, 74% replied in the affirmative. This rose to 90% for the phase 2 “abductee group” and dropped to 65% for the phase 2 “contactee group.” This indicates that they experienced the classic symptoms of sleep paralysis with or without a real alien presence in their home. 

     Our next question is designed to separate sleep paralysis experiencers from those who might have endured a real abduction. We asked: 

 Have you been awake and able to move your body, but observed a non-human/ET presence and became paralyzed? 

(Survey Takers N:507)  

     When asked if they had been awake but then saw a non-human in their environment and became unable to move or cry out, 36% of the phase 1 survey takers replied in the affirmative. The percentage of wakeful contact increased dramatically to 60% in the phase 2 “abductee group” and dropped to 25% in the phase 2 “contactee group.” The highly significant statistic for the “abductee group” could be an indication that their events are real and not sleep state generated.

      Many ET contact experiencers believe their experiences are real because they and others, in their homes, retain the same experiential memories. When there is unusual physical evidence attached to these memories, it is difficult to find an adequate prosaic explanation such as sleep paralysis and H/H hallucinations. 

     Some abductees/experiencers are returned to their beds, but others end up locked outside of their homes. Some awaken on their roofs, in their vehicles, or even in someone else’s home. Sometimes they find mud and vegetative matter in their beds. Others find they are no longer dressed in their own clothing, but in a stranger’s nightshirt. Sometimes experiencers find landing trace evidence on their property.

     Most academic psychologists ignore these unique characteristics associated with nocturnal bedroom abductions. Instead they attempt to dismiss reports made by abductees/experiencers as sleep paralysis and H/H hallucinations despite the evidence to the contrary. There are several reasons for this such as political agendas, the great taboo, and the failure to do real science. 

     Dating back to the 1950's, a few courageous scientists have stepped outside politically acceptable constraints and have advanced our scientific knowledge of UFO related phenomena. However, UFOs and ET contact have been taboo topics in mainstream academic and scientific circles until recently. Beginning on December 16, 2017, soft disclosure began to unfold. Then on April 5, 2022, the Pentagon's Defense Intelligence Agency released 1574 declassified documents through a Freedom of Information Act Request made in 2018. The documents contain information on a capture and release program on humans, unaccounted for pregnancies, levitation, and telepathic communication. Here are some of their findings:

  • Warping space-time
  • Electromagnetic heating and radiation burns
  • Damage to nervous system, cognitive damage
  • Hair loss
  • Nausea
  • Unaccounted for pregnancies
  • Telepathy
  • Poltergeist activity, orbs, shadow entities, and other high strangeness events in home
  • Marian apparitions


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May/June 1998.   7/2/2009.

Friedman, Stanton & Kathleen Marden. Chapter 14. Science was Wrong. Franklin Lakes, NJ: New Page Books. 2010.

Hufford, David J.. The Terror that Comes in the Night. Philadelphia, PA: .University of PA Press. 1982.

Mack, John, Caroline McLeod, Barbara Corbisier. “A More Parsimonious Explanation for UFO

Abduction”. Psychological Inquiry (7:2) 1996.

Marden, Kathleen. “The Conundrum of Alien Abduction”, MUFON 2010 International UFO Symposium Proceedings. July 2010.

Randle, Kevin D., Russ Estes, & William P. Cone, PhD. The Abduction Enigma. New York, NY: Tom Doherty Assoc., 1999.

“Sleep Paralysis”. January 26, 1999. Visited 3/2010.

“Sleep Paralysis”.  Visited 12/2011.

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“What are Hypnopompic Hallucinations?”. Visited 1/2012. 


© Copyright updated on 4/22/2022