"Poltergeists (from the German 'noisy ghosts') usually manifest as strange electrical effects and unexplained movement of objects. At one time, these phenomena were thought to be due to ghosts, but after decades of investigations by researchers, notably by William G. Roll, the evidence now suggests that poltergeists are psychokinetic (PK) effects produced by one or more individuals, usually troubled adolescents. The term RSPK, meaning Recurrent Spontaneous [Psychokinesis], was coined to describe this concept." ¹

Because the phenomena of poltergeists and ghosts (or recurrent apparitions) have often been associated with each other, it is important to discuss a few differences between the two.

While recurrent apparitions are typically unobtrusive, poltergeists are extremely noisy, producing such sounds as bangs, thuds, rappings, or crashes, and include the movement of objects, such as the throwing of crockery and small furniture.

As psychic investigator Harry Price put it, "a poltergeist is mischievous, destructive, noisy, cruel, erratic, thievish, demonstrative, purposeless, cunning, unhelpful, malicious, audacious, teasing, ill-disposed, spiteful, ruthless, resourceful, and vampiric. A ghost haunts. A poltergeist infects." ³

In the late 1970's, parapsychologists Alan Gauld and A.D. Cornell attempted to classify the characteristic of poltergeist phenomena by analyzing approximately 500 reported poltergeist outbreaks. "They discovered that 64% of the cases involved movement of small objects, 58% percent were most active at night, 48% involved raps or knocking, 36% featured movement of large objects, 24% lasted over one year, 16% involved communication with an 'entity', and 12% involved the shutting and opening of doors and windows." ³ Typically, people are not seriously hurt during poltergeist outbreaks, despite assaults that result in pinches, scratches, or bites. While severe bodily harm is not unknown, it is highly uncommon.

While poltergeist phenomena is extremely difficult, if not impossible, to study in the laboratory, such phenomena provides a great opportunity for field investigators. However, investigations involving poltergeists are extremely difficult to conduct, not because poltergeists are dangerous, but because of the often severe psychological tensions present. Thus the investigator must be prepared to deal with whatever emotional problems are occurring in addition to the paranormal phenomena.

Perhaps one of the best known cases of poltergeist activity took place in a lawyer's office in Rosenheim, Germany. Hanging lamps were reported to swing violently, light bulbs would shatter, electrical fuses would blow out, the telephone would ring constantly with no one on the other end, and thousands of calls never made were recorded by the telephone company and billed to the lawyer. During investigations into the phenomena, the activities increased to include paintings beginning to swing and turn over on their hooks, banging sounds, drawers opening by themselves, contents being emptied from files and cabinets, and heavy furniture moving. ²

After investigation by electricians, engineers, police officers, journalists, and finally some experienced poltergeist investigators (all in all, nearly forty first-hand witnesses were involved in the case), it was discovered that the activity seemed to center around an eighteen-year-old secretary employed at the office named Annemarie. When Annemarie was sent away on leave, the disturbances stopped immediately. Similar disturbances were reported at the new location of her employment, but they were less obvious and eventually died off. ²

The early explanation for poltergeist activity was that it was caused by a malicious spirit or demon, and often priests were called to exorcise the demon. However, in the 1960's, William Roll studied over a hundred poltergeist outbreaks, focusing his research on the psychological factors involved. What he determined was that poltergeist outbreaks are the product of a living individual. It has often been noted that poltergeist activity centers around an adolescent (called the poltergeist focus or agent), typically one who is suffering from severe psychological stress. Parapsychologists maintain that the poltergeist agent (though not always an adolescent) is somehow producing the phenomena unconsciously through psychokinesis (PK), thus the use of the term recurrent spontaneous psychokinesis, or RSPK phenomena.

One explanation for poltergeist activity, in conjunction with the belief that it is caused by PK, is that it is an "extrasomatic (exterior to the body) [expression] of psychological stress in the same way [that] an ulcer is a psychosomatic expression of such stress." Basically poltergeist phenomena are "external manifestations of repressed anger and hostility," typically from adolescents. The poltergeist effects help the agent to release the feelings of stress, and often once the stress factor is removed, the phenomena ceases. ²

However, some parapsychologists point out that several thousand young adults experience such psychological trauma. What is it then, then triggers these few individuals to become poltergeist agents? Some studies in neurophysiology suggest that there may be a link between poltergeist agents and epileptic tendencies, however this theory is still highly speculative. ²