Alien abduction claims explained

Abduction stories are strikingly similar. Victims wake up and find themselves paralyzed, unable to move or cry out for help. They see flashing lights and hear buzzing sounds. Electric sensations zing through their bodies, which may rise up in levitation. Aliens with wrap-around eyes, gray or green skin, lacking hair or noses, approach. The abductee’s heart pounds violently. There’s lots of probing in the alien ship. Instruments are inserted in their noses, navels, or other orifices. It’s painful. Sometimes sexual intercourse occurs.

Then it’s over, after seconds or minutes. The intruders vanish. Victims are back in their own beds and can move again.

Researcher Susan Clancy, Richard McNally, a professor of psychology at Harvard, and other researchers tie such horrifying happenings to sleep paralysis, a condition where the usual separation between sleep and wakefulness gets out of synchronization.

When you dream, you are paralyzed. It’s a natural adaptation to prevent people from lashing out, jumping out of bed, walking into doors or windows, and otherwise injuring themselves. But it’s possible to wake up while still paralyzed.

“We can find ourselves hallucinating sights, sounds, and bodily sensations,” Clancy says. “They seem real but they’re actually the product of our imagination.” One researcher describes it as “dreaming with your eyes wide open.”

Bizarre effects aside, sleep paralysis is as normal as hiccups. It’s not a sign of mental illness. About 25 percent of people around the world have experienced it, and about 5 percent get the whole show of sight, sound, tactile hallucinations, and abduction.

Some of these people become completely absorbed by what happened and seek an explanation of it. That can lead them into a grab bag of different techniques well known to those with a rich fantasy life and a distaste for scientific explanations.

Clancy details her findings in a book, “Abducted: How People Come to Believe They Were Kidnapped by Aliens,” to be published by the Harvard University Press,