Poltergeist

In folklore and parapsychology, a Poltergeist (German for "noisy ghost") is a type of ghost or other supernatural entity which is responsible for physical disturbances, such as loud noises and objects being moved or destroyed. They are purportedly capable of pinching, biting, hitting, and tripping people. Most accounts of poltergeists describe the movement or levitation of objects such as furniture and cutlery, or noises such as knocking on doors.

They have traditionally been described as troublesome spirits who haunt a particular person instead of a specific location. Such alleged poltergeist manifestations have been reported in many cultures and countries including the United States, India‚ Japan, Brazil, Australia, and most European nations. Early accounts date back to the 1st century.

The word poltergeist comes from the German language words poltern ("to make sound" and "to rumble") and Geist ("ghost" and "spirit"), and the term itself translates as "noisy ghost", "rumble-ghost" or a "loud spirit".

Many claimed poltergeist events have proved on investigation to be pranks. Skeptic Joe Nickell says that claimed poltergeist incidents typically originate from "an individual who is motivated to cause mischief". According to Nickell:

"In the typical poltergeist outbreak, small objects are hurled through the air by unseen forces, furniture is overturned, or other disturbances occur -- usually just what could be accomplished by a juvenile trickster determined to plague credulous adults."

Nickell writes that reports are often exaggerated by credulous witnesses.

"Time and again in other “poltergeist” outbreaks, witnesses have reported an object leaping from its resting place supposedly on its own, when it is likely that the perpetrator had secretly obtained the object sometime earlier and waited for an opportunity to fling it, even from outside the room—thus supposedly proving he or she was innocent."

According to research in anomalistic psychology, claims of poltergeist activity can be explained by psychological factors such as illusion, memory lapses, and wishful thinking. A study (Lange and Houran, 1998) wrote that poltergeist experiences are delusions "resulting from the affective and cognitive dynamics of percipients' interpretation of ambiguous stimuli".

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