Non-human beings take people, usually from their bed at night or from a car, examine them and return them with gaps in memory. Hypnosis can bring back what happened.
No evidence
The experiences are real. The abductions are not supported.
People who report abduction are usually sincere and often deeply affected. The evidence points to sleep paralysis, memories shaped by hypnosis and belief, and cultural images. No physical evidence has ever been verified.
Last reviewed: 15 November 202615 sourcesVersion 1.0
Short answer
Abduction stories became widespread after the Betty and Barney Hill case of 1961 and the books of the 1980s and 1990s [10]. Researchers at Harvard studied people who report abductions. They found ordinary, mentally healthy people with high rates of sleep paralysis and a greater tendency to form false memories in word-list tests [1][3][13]. Most detailed stories were “recovered” under hypnosis, which makes people more confident in memories without making them more accurate [6]. In more than sixty years no implant, tissue sample, medical record or recording has confirmed a single case [14].
What supporters can show
Verified
Many sincere, mentally healthy people report it
Source
Spanos and colleagues (1993) found that people reporting UFO experiences showed no more psychological disturbance than comparison groups [5].
Shows
The reports cannot be dismissed as mental illness or lying.
Does not show
That the events happened as remembered.
Verified
Their bodies react as if to real trauma
Source
In a 2004 study, people who reported abduction listened to scripts of their own story while heart rate and skin conductance were recorded. Their reactions were similar to those of patients with post-traumatic stress disorder listening to scripts of their own traumas. The study was small, with 10 people reporting abductions and 12 comparison participants [2].
Shows
The fear is genuine and the memory is deeply felt.
Does not show
What caused the memory. The authors concluded that a sincerely held memory produces this reaction whether or not the event took place [2].
Verified
The stories share the same elements
Source
Accounts collected by abduction researchers repeat a pattern: paralysis, a presence in the room, small grey beings, a medical examination, missing time [11][14].
Shows
A shared experience or a shared source.
Does not show
That the source is outside the person. A common brain state (sleep paralysis) and common cultural images also produce similar stories [3].
Partly verified
Some cases have two witnesses
Source
Betty and Barney Hill both described a light that followed their car on a road in New Hampshire in September 1961 [10].
Shows
Two people saw something in the sky they could not identify and arrived home later than expected.
Does not show
The abduction itself. Those details came out in hypnosis sessions in 1964, after Betty had told Barney about her vivid dreams. Their psychiatrist, Dr Benjamin Simon, did not accept that the abduction had happened as described [10].
Verified
Serious academics took it seriously
Source
John Mack, a Pulitzer Prize-winning Harvard psychiatrist, published Abduction in 1994 after working with dozens of people who reported abductions [11].
Shows
The subject deserves careful study.
Does not show
That his conclusions were right. Other researchers who examined the same kind of cases found the memory and sleep explanations in column 2 [1][3].
Could not verify
Claims that supporters often repeat and that we looked for but could not confirm in a reliable source.
Implants. Objects removed from people's bodies have been described as alien. We found no peer-reviewed analysis showing any of them to be of non-earthly origin.
Missing pregnancies. Stories of pregnancies that vanished after an abduction. We found no documented medical case.
“Millions of abductees.” A 1991 Roper survey was read as showing millions of hidden abductees. The estimate came from indirect questions such as waking up paralysed or seeing unusual lights, not from reports of abduction [12].
What science found
Sleep paralysis matches the core of the experience
During sleep paralysis the brain wakes up while the body is still locked in dream sleep. People cannot move, and often feel a presence in the room, see figures, hear buzzing or feel pressure on the chest. A review of 35 studies found that about 8% of the general population have had it at least once, and 28% of students [4].
Most abduction stories begin in bed at night, and people reporting abductions often describe sleep paralysis [3].
Hypnosis makes memories feel surer, not truer
In 1985 the American Medical Association reviewed the research and concluded that memories “refreshed” by hypnosis are less reliable than ordinary memory. People recall more, but much of it is wrong, and they become more confident in all of it [6]. Memory researchers have also shown that people can be led to remember detailed events that never happened [7].
Many abduction stories were assembled in hypnosis sessions led by researchers who already believed in abduction [14].
People who report abduction form false memories more easily
In a Harvard study, people who reported abductions and comparison groups heard lists of related words, such as bed, rest, tired, dream, which all point to a word that is never read out. Later they were asked which words they had heard. The group that reported recovered memories of abduction falsely “remembered” such unread words more often than the others [1][13].
This does not mean they are lying. It means their memory fills gaps more easily.
People with no experience tell similar stories under hypnosis
In 1977 Alvin Lawson and a colleague asked hypnotised volunteers who had never reported an abduction to imagine being abducted. Their accounts were very similar to those of people who said they had really been taken [8]. The study was small, and Lawson himself noted that no hypnotic session can entirely avoid unconscious cueing, but it shows how readily such accounts can be produced.
The figure in the room changes with the culture
The same sleep experience was explained as a witch, a demon or a ghost long before UFOs. In Newfoundland it is the “Old Hag” [15]. In Abruzzo, Italy, it is the Pandafeche, a witch or cat-like creature that sits on the sleeper's chest [9]. In a culture full of UFO films and books, the figure is often a grey alien.
No physical evidence in sixty years
Thousands of cases have been collected since 1961. None has produced an object, tissue sample, medical record or recording that independent scientists could examine and confirm [14].
What is still open
Why some people have repeated, vivid episodes while most never do, and why some cope easily while others are badly shaken. Researchers are still studying how sleep, personality and belief combine [14].
If this happens to you
Waking up unable to move, with a feeling that someone is in the room, is common and harmless, though it can be terrifying [4]. A doctor or sleep specialist can help, and regular sleep makes episodes less frequent.
Be careful with anyone who offers hypnosis to “recover” what happened. It can create memories that feel real and are hard to get rid of [6].
Sources
Clancy, S. A., McNally, R. J., Schacter, D. L., Lenzenweger, M. F., & Pitman, R. K. (2002). Memory distortion in people reporting abduction by aliens. Journal of Abnormal Psychology, 111(3), 455–461.
McNally, R. J., Lasko, N. B., Clancy, S. A., Macklin, M. L., Pitman, R. K., & Orr, S. P. (2004). Psychophysiological responding during script-driven imagery in people reporting abduction by space aliens. Psychological Science, 15(7), 493–497.
McNally, R. J., & Clancy, S. A. (2005). Sleep paralysis, sexual abuse, and space alien abduction. Transcultural Psychiatry, 42(1), 113–122.
Sharpless, B. A., & Barber, J. P. (2011). Lifetime prevalence rates of sleep paralysis: A systematic review. Sleep Medicine Reviews, 15(5), 311–315.
Spanos, N. P., Cross, P. A., Dickson, K., & DuBreuil, S. C. (1993). Close encounters: An examination of UFO experiences. Journal of Abnormal Psychology, 102(4), 624–632.
Council on Scientific Affairs, American Medical Association (1985). Scientific status of refreshing recollection by the use of hypnosis. JAMA, 253(13), 1918–1923.
Loftus, E. F., & Pickrell, J. E. (1995). The formation of false memories. Psychiatric Annals, 25(12), 720–725.
Lawson, A. H., & McCall, W. C. (1977). What can we learn from hypnosis of imaginary abductees? MUFON UFO Symposium Proceedings.
Jalal, B., Romanelli, A., & Hinton, D. E. (2015). Cultural explanations of sleep paralysis in Italy: The Pandafeche attack and associated supernatural beliefs. Culture, Medicine, and Psychiatry, 39(4), 651–664. Source
Fuller, J. G. (1966). The Interrupted Journey. Dial Press.
Mack, J. E. (1994). Abduction: Human Encounters with Aliens. Scribner.
Hopkins, B., Jacobs, D. M., & Westrum, R. (1992). Unusual Personal Experiences: An Analysis of the Data from Three National Surveys. Bigelow Holding Corporation.
Clancy, S. A. (2005). Abducted: How People Come to Believe They Were Kidnapped by Aliens. Harvard University Press.
Hufford, D. J. (1982). The Terror That Comes in the Night: An Experience-Centered Study of Supernatural Assault Traditions. University of Pennsylvania Press.
Change log
15 November 2026: First publication. Verdict: No evidence.