Besides apparitions of the newly dead and the haunting ghost, there is also the poltergeist, the most feared of all ghosts. While other ghosts might seem merely "eerie", poltergeists are loud, mischievous, willful, and destructive. While they seldom appear visually, these mysterious entities tend to make a lot of commotion : objects float in mid-air, furniture moves around, fires ignite, lights flash, puddles of water appear out of nowhere, and showers of stones occur both inside and outside the house. These physical phenomena are often accompanied by a variety of raps, scratches, knocks, explosion noises, animal noises, laughter, whispers, and strangely mechanical- or artificial-sounding voices.

In many respects, the poltergeist seems an equal-but-opposite version of a haunting ghost. While ghosts tend to be more frequently seen than heard, poltergeists are far more commonly heard than seen. People often mention how strangely quiet the air seems to get when a ghost appears; and when a ghost does make audible sounds, they are usually nonverbal whistles, chirps, screams, or moans, all of which are subjective right-brain sounds that need to be interpreted by the listener. The poltergeist, on the other hand, seems to be more of a no-nonsense left-brain communicator; many have been known to employ a sophisticated linear communication code consisting of knocks, raps, and scratches, and a number have even been known to use language, sometimes speaking and occasionally even using the written word. While haunting ghosts� communication attempts are usually limited to nonverbal signals, gestures, and images, poltergeists virtually never resort to symbol or metaphor to get their messages across; they�re just not that subtle.

While the haunting ghost seems tied to a particular place or physical object, poltergeists instead usually have a connection to a particular living person, its �focus� subject. Sometimes the poltergeist seems linked to both a physical location and a particular person, and the disturbances only occur when the focus subject is at the one location. But this is not a hard and fast rule; some poltergeists have not been tied to a particular location, and were able to follow their focus subject from place to place, and other poltergeists have not had a focus subject at all.

The general consensus among parapsychologists today is that poltergeists are not disembodied entities at all, but instead, these disturbances are held to be the unintentional and unconscious manifestation of the focus subject�s own psychic ability. There is no �ghost� at all, these researchers maintain; all the trouble is being unconsciously caused by the focus subject and no one else. However, this theory fails to account for all the facts. A number of poltergeist cases have had no focus subject at all, which has led other researchers to ask if the focus subject is simply �leaking� psychic energy that disembodied entities occasionally discover they can use. If so, then the focus subject is not the author of the disturbances at all, but instead takes on the role of an unwitting victim, while the poltergeist would be something of a psychic parasite.

Whereas the haunting ghost seems to be very subjective, introverted, and self-oriented, caught up in their own private memories and emotional turmoil, the poltergeist usually seems quite objective, extroverted, and other-oriented, not particularly interested in its own memories or emotions at all, but very attentive to the memories, emotions, and reactions of others. While most haunting ghosts never notice the presence of others, poltergeists always seem to be aware of what�s going on around them in the real world. In fact, many researchers have remarked that poltergeists seem to like having an audience and getting attention from others, almost as if they feed off others� attention and emotional reactions. Many poltergeists have demonstrated the unnerving ability to read the thoughts, memories, and history of others, but rarely seem to reveal any well-defined thoughts, memories, or history of their own. In fact, even in the rare cases when poltergeists do communicate verbally, as often as not their statements are incoherent and meaningless, like a parrot mixing and matching phrases it has heard without any insight into what they mean.

While the haunting ghost is known for its fixed and consistent behavior, poltergeists are known for being unpredictable and inconstant. Ghosts tend to be seen again and again at the same place, doing the same thing in the same clothes; many even adhere to a specific timetable, appearing at regular intervals, or on the same anniversary date year after year. But poltergeist manifestations tend to be erratic, appearing suddenly, carrying on for anywhere from a few weeks to a year or two, and then inexplicably stop just as suddenly, usually never resuming again. Poltergeists, in short, seem to exhibit much more free will than the typical haunting ghost does.

In one study, more than 80% of poltergeists did not seem to present any clear personal identity. Poltergeists often seem uneasy about the whole concept of self-identity; in fact, one of their favorite tricks is destroying all portraits and photographs in the house.

Interestingly, in a number of �possession� cases (which are like poltergeists in many respects) the possessing spirit has seemed to lack any sense of personal identity, often calling itself �no one�, �nobody�, or �nothing.� And while possessing spirits often claim to be individuals, they almost never reveal any trace of real personal identity. Swedenborg�s explanation for this is a lot like the Binary Soul Doctrine; he taught that such possessing spirits had their personal memory taken from them at death, forcing them to rely on the memory and abilities of the people they are able to possess.

While the haunting ghost seems constitutionally incapable of presenting a false image of itself to others, the poltergeist seems both comfortable and adept at doing this. In fact, while the haunting ghost may not know anything else, it is at least clear about its own identity, about who it is. But at least as often as not, the poltergeist leaves us not only with questions about its true identity, but leaves us even wondering if it itself really knows who or what it is.

Of course, the reader will by now realize that many of the classic characteristics of poltergeists are exactly what one would expect from a disembodied conscious mind that had lost its unconscious. It would have no sense of identity and no sense of right and wrong, but it would still be very active and willful, and would still be able to communicate through language and other linear codes. (One might object that the poltergeist often seems stupid, while one of the primary qualities of the conscious mind is rational intelligence. However, while every child is born with a conscious left-brain mind, it takes many years of practice to harness and use that inherent intelligence.) Being objective and other-oriented, the poltergeist would observe that most other beings do possess fairly well defined identities, and would realize that this was something it lacked. Feeling unsure about its own identity, it might seek feedback from others to substantiate and re-define its own sense of self. Having no well-defined sense of perspective, context, or self- identity, it would at times become confused and disoriented when observing the inner mental depths of others. But since the conscious mind focuses primarily on the differences and distinctions between things, the poltergeist would focus most of its attention on the differences and distinctions between itself and everything else it observed. In its mind, it would seem alone and alienated from its environment, and its actions would illustrate that perspective, emphasizing that it was different from those around it, behaving divisive and destructive rather than related and supportive. The poltergeist, then, would be the ultimate alienated being.

Another thing which suggests that poltergeists are disembodied conscious minds is the fact that, in a number of cases, the poltergeist's voice seemed strangely artificial or mechanical. As it turns out, this same observation has been made by NDErs in the dark void of the first stage. In P.M.H. Atwater's book Beyond the Light, one NDEr encountered beings in the dark void who communicated with "a clicking sound ... they were jeering and tormenting, not evil, exactly, but more mocking and mechanistic." Similarly, poltergeists often use knocking or rapping codes to communicate, their voices have also been described as artificial or mechanical, and they have also been described as more jeering and tormenting than truly evil. And like poltergeists, the dark void has also been shown to have strong "left-brain conscious mind" characteristics.