Peter Suedfeld & John Geiger. Miracles: God, Science, and Psychology in the Paranormal. Editor: J Harold Ellens. Volume 2: Medical and Therapeutic Events. Westport, CT: Praeger, 2008.
People sometimes sense, see, or hear another being in situations in which the actual presence of another being is highly improbable, if not impossible. Psychologists refer to this as the “sensed presence experience.” Sensed presence experiences occur in a wide variety of situations, to a wide variety of people; and the presences themselves vary in appearance, identity, and behavior. There are many kinds of sensed presence phenomena. They include psychotic, feverish, and drug-induced hallucinations; angelic and other religious visitations, ghosts, “corner of the eye” glimpses of someone almost seen or almost heard, quite common among recently bereaved persons; vivid dreams and daydreams, hypnagogic images in the “twilight” state between sleep and full awakening; and misinterpretations of actual percepts, as when the shadow of a tree or the rustling of a bush is perceived as a human being or an animal. This chapter will not deal with such percepts. Rather, we address experiences that are reported by people in extreme and unusual environments (EUEs), which are of interest to psychologists because no obvious explanation presents itself.
Sensed presences in EUEs may be seen, heard, and sometimes touched; but commonly, they are, literally, sensed. Their identity may be unknown to the perceiver, although even in such cases people usually do know whether the being is male or female. Sometimes a presence is recognized as a religious figure, friend, acquaintance, or relative. They often appear when the person is weakened by exhaustion or illness; on the verge of death from cold, thirst, or starvation; lost and alone; or in an unusually stimulus-poor environment. Most surprisingly, they do not just serve as companions: they actually help the person in trouble, sometimes by offering useful information or advice and at other times by seeming to take a hand in whatever needs to be done to improve the chances of survival. This chapter will describe episodes in which such apparitions were reported, analyze the causal conditions, and review the theoretical explanations that have been advanced for the phenomenon.
Sensed Presence Experiences in EUEs
The sensed presence often occurs in the wilderness: mountains, ice fields, jungles, and the ocean. The experience has also been encountered underwater by divers and aloft by pilots and astronauts. Other cases have been reported by survivors of man-made conflagrations, such as the September 11, 2001, terrorist attacks on the World Trade Center, and by prisoners of war. There are several environmental factors that are common to such situations, despite their obvious differences. One characteristic is a relatively unchanging and homogeneous physical and social stimulus environment. Other relevant factors can include physical privation, such as hunger, thirst, illness, or injury; psychological stress; unusual temperatures (very hot, very cold, or alternating between the two); and a perception of danger.
A survey of 58 recorded cases of sensed presence experiences in EUEs found examples among explorers in tropical jungles, pilots and astronauts, and divers (Geiger, in press). Man-made EUEs have also produced cases involving prisoners of war, concentration camp inmates, and other survivors. But all of these sources represent a relatively small number of the total cases studied (Geiger, in press). The greatest number, almost half, occurred in mountainous settings, both at extreme elevation and at lower altitudes. The next most common grouping involved the oceans: solo sailors, crewmen on racing yachts, and shipwreck survivors. That category is followed by polar explorers.
Examples of sensed presence experiences illustrating the three most common categories of EUEs follow.
Climbing a mountain represents the most common context for a sensed presence in EUEs. A recent study of 33 Spanish climbers involved in high-altitude climbs found that one-third had experienced hallucinatory episodes, the most common being “the sensation of an imaginary accompanying presence behind one’s own body” (Garrido, Javierre, Ventura, & Segura, 2000, p. 148). Dr. Griffith Pugh, an expert on the physiology of cold and altitude, acknowledged that many climbers have encountered sensed presences and attributed them to a “decay of brain functions” caused by high altitude (Hellier, 1971, p. 10).
An early example was recorded by British climber Frank Smythe, who in 1933 came to within about 300 meters of the summit of Mount Everest during a solo ascent. Smythe had been struggling against the effects of extreme altitude when he decided he had reached the limit and must turn back. Smythe felt as if an unseen companion was aiding him throughout his arduous climb. “This feeling was so strong that it completely eliminated all loneliness I might otherwise have felt. It even seemed that I was tied to my ‘companion’ by a rope, and that if I slipped ‘he’ would hold me” (Ruttledge, 1934, p. 164). At one point, Smythe stopped to rest and pulled out a Kendal mint cake. He broke off a piece and turned to share it with his “companion,” and it was “almost a shock” to find there was no one to give it to. Only when he descended to a camp where another, flesh and blood, member of the expedition was waiting for him did his unseen friend depart. “I suddenly felt alone,” wrote Smythe (Ruttledge, 1934, p. 165).
Smythe was not the first climber to report the phenomenon, and he was certainly not the last. Maurice Wilson, a British climber with a mystical bent, was on Everest within a year of Smythe, and he too recorded a sensed presence. Wilson’s was a singularly ill-planned and ill-equipped expedition. He had no climbing experience and felt that his religious faith would be sufficient to see him to the top of the world’s tallest mountain. He did not survive his 1934 climb, but his diary was found. In it, he recorded the feeling, as he lay partially snow-blind and suffering from the elevation, that someone was with him: “Strange but I feel that there is somebody with me in the tent all the time” (Roberts, 1957, p. 146).
The sensed presence is a common visitor on climbs, including some of the most famous ascents in history. In 1950, in a reconnaissance in preparation for the conquest of the Himalayan peak Annapurna, the world’s 10th highest, a climber on the French team led by Maurice Herzog described to his climbing partner a sensed presence: “I thought I heard someone else behind me … a third man. He was following us. I wanted to call out to you. I could not. I glanced behind me rather furtively, to set my mind at rest. But like an obsession, the feeling of someone else there kept coming back to me” (Herzog, 1952, p. 52).
On September 24, 1975, British climbers Doug Scott and Dougal Haston completed the ascent of the South West Face of Everest. They arrived at the summit at 6 PM, after a 14-hour climb. After a rest they started down, but thick clouds obscured the moonlight. Only 48 meters (428 feet) in elevation below the summit, they were forced to spend the night. They dug a hole in the snow but by 8 PM had exhausted their supplementary oxygen supply and were without food. A small propane-butane stove helped stave off the bitter, -30 degree temperature, but fuel ran out at midnight and they were forced to endure intense cold. The expedition’s medical officer, Charles Clarke, subsequently reported that both Scott and Haston “told of a curious sensation that a third person had been sharing the snow hole during the night” (Clarke, 1976, pp. 92-93).
Reinhold Messner, perhaps the greatest of all climbers, encountered a sensed presence on both Nanga Parbat and Everest. He felt the companions provided “psychological help to stem the loneliness” and that his body was“inventing ways to provide company” (R. Messner, interview with John Geiger, January 13, 2004). Messner recorded one of the experiences during his 1978 solo conquest of Nanga Parbat: “I am holding a conversation with someone who is sitting at my side. Is it human? It seems there is another presence besides my own. That is all I can say. It isn’t just a voice I hear, I actually sense a physical presence” (Messner, 1980, p. 160).
The Polish climber Jerzy Kukuczka was competing with Reinhold Messner to become the first person to reach the summit of all 14 of the world’s 8,000-meter (28,000-feet) peaks. In October 1981, Kukuczka opted to tackle Makalu, the fifth highest mountain in the world, located 22 kilometers (14 miles) east of Everest. Kukuczka, climbing with two others, initially attempted an assault on Makalu’s West Face but was forced to turn back. He then determined to try again by another route, up the North-West Ridge. Unable to convince the others to join him, he proceeded alone and did reach the summit. He later described how, at 8,000 meters, he dug out a platform and pitched his tent with difficulty during a hard wind. Once inside the tent, Kukuczka, who was exhausted, started to brew some tea. He then realized he had company: “Just then I experienced a quite inexplicable feeling that I was not on my own, that I was cooking for two people. I had such a strong feeling that someone else was present that I felt an overpowering need to talk to him” The next day weather conditions continued to deteriorate and he came across deep, collapsing snow. As he fought on, he became conscious that he was “standing still waiting for the other one,” and he said, “From time to time I let him pass, so that he could go ahead.” (Kukuczka, 1992, p. 40).
The Australian climber Michael Groom described a particularly vivid encounter he experienced while under great distress, spending the night at high altitude on Kangchenjunga in 1987. “I felt the presence of someone in the tent next to me. He knelt close by my right side, placed a firm hand in the middle of my back and lifted me into an upright position. My breathing now became easier as I rested my dizzy head between my knees but I still felt the presence of someone watching over me” (Groom, 1997, p. 97).
American Steve Swenson, during a 1994 climb of Everest, was forced to spend two nights at 27,000 feet. During the second night, he had three separate sensed presence experiences. One involved a woman who urged him to stay awake through the night, when sleep would have risked death; a second he felt was a jolly Sikh man who implored him in the morning to continue his descent; and finally a third, unidentified being accompanied him on the way down to safety. “These characters were very real, and I was taking their advice … Everything, every piece of advice I was getting, was exactly what I needed to do” (S. Swenson, interview with John Geiger, October 10, 2005).
Paul Firth, a South African climber who is an anesthesiologist by profession, experienced a sensed presence on Aconcagua, in Argentina. When confronted with an awareness of acute danger, he “suddenly felt like there was somebody behind” him. This unseen being accompanied him down the slope, always behind him, slightly over his left shoulder, encouraging him along. When he felt stronger, further down the mountain, the companion disappeared just as suddenly. Firth wrote of his experience, “Whatever the physiological details of these experiences … who can say why these helpful ghosts wander in the penumbral world of the edges of our perception?” (P. Firth, 2003).
Solo Sailors, Racing Yacht Crewmen, and Shipwreck Survivors
Joshua Slocum in 1895 embarked on his 40-foot sloop to attempt what would become the first solo circumnavigation of the world. He succeeded, and also provided the first modern description of the sensed presence experience. Several times over the course of the voyage, Slocum was joined by a sensed presence. The initial encounter occurred during the first leg of the journey when, off the Azores, he was hit by fierce winds. To make matters worse, Slocum fell seriously ill, apparently from food poisoning, and was collapsed in the cabin, near the wheel, when a “strange guest” visited him. The visitor told Slocum that he was there to “aid” him, saying, “Lie quiet … and I will guide your ship to-night” (Slocum, 1900/2003, p. 24). Before his illness, Slocum had been reading Washington Irving’s Life of Columbus, and he convinced himself that the presence was the pilot of the Pinta. When Slocum finally recovered, after 48 hours, he found the sloop on its correct course for Gibraltar. He felt, he said, that he had been “in the presence of a friend and a seaman of vast experience.” This “friend” reappeared later in Slocum’s journey.
In 1953, two deserters from the French Foreign Legion, one a Finn and the other a Swede, jumped ship en route to Vietnam and found themselves adrift on a small raft in the Strait of Malacca. They had hoped to be picked up in a matter of a few hours in the busy shipping lane, but they failed to attract the attention of the commercial vessels that passed, and they soon drifted into the Indian Ocean, without provisions, starving, dehydrated, exposed to the elements, and pursued by sharks. The Swede died during the 32-day ordeal, but the Finn, a 24-year-old named Ensio Tiira, survived. He later wrote, “For the whole voyage I’d had the strange feeling that someone else was with me, watching over me, and keeping me safe from harm” (Tiira, 1954, p. 141).
Another solo sailor to have experienced a sensed presence was the German doctor Hannes Lindemann, who made a remarkable solo Atlantic crossing in a 17-foot rubberized canvas folding boat in 1956. Lindemann wanted to test a theory that self-mastery, through hypnotic and autogenic meditation techniques, would aid his psychological state during the voyage. He sensed that he was joined by an African companion who would speak to him and provide reassurance. It was a common sensation during the journey: “Often, as I awoke, I looked around for my companion, not realizing at once there was nobody else with me” (Lindemann, 1958, p. 144).
Dr. David Lewis came from the Lindemann tradition, and entered the 1960 Single-handed Transatlantic Sailing Race in order to conduct medical research, keeping a daily log of his mental and physical responses to danger and exhaustion. Nearing the Grand Banks, he recorded experiencing the feeling that he was “not alone.” He previously had a vivid sense “that another person was at the helm” (Lewis, 1961, pp. 48-49).
In another solo Atlantic crossing, American Robert Manry, exhausted from 48 hours without sleep, and popping “stay awake” pills because of sailing conditions, became aware that he was “not alone”; he said, “Someone, a man, was on Tinkerbelle with me … He was friendly.” Manry never spoke aloud to his new friend, but says, “We did converse in a miraculous, soundless way.” At some point the man took over the tiller from the exhausted Manry, who “became the passenger” (Manry, 1967, pp. 91-93).
There are numerous other accounts of experiences with sensed presence during ocean travel. Some of these, unlike our previous examples, were by survivors of shipwreck. After surviving a torpedoing during World War II, 14 merchant sailors drifted on the Atlantic Ocean for 50 days before the only 2 survivors were rescued. One, Kenneth Cooke, reported that a young crew-mate who had died on the 25th day had afterward repeatedly spoken to him and had said that some of the men would survive. These messages kept him alive—in one instance, as he was contemplating throwing himself over the side to end his ordeal (Cooke, 1960).
In another case, a woman drifting in a dinghy on the Pacific Ocean told her five companions that during a heavy storm, she had counted seven people in the boat and that a presence behind her had helped them to fight the storm (Robertson, 1973). In their study of survival at sea, E.C.B. Lee and Kenneth Lee (1980) wrote of the experience as being common: “There are many instances where survivors have felt an Unseen Presence, helping and comforting them” (Lee & Lee, 1980, p. 203).
The best-known sensed presence incident was reported by the famous polar explorer Sir Ernest Shackleton during his ill-fated 1914-17 Imperial Trans-Antarctic Expedition. Shackleton and two companions, Thomas Crean and Frank Worsley, who had already survived a harrowing Antarctic shipwreck and a long journey in an open boat, undertook a trek across the mountains of South Georgia Island to reach potential rescuers for the remainder of their original party. Dehydrated, wet, cold, tired, and poorly equipped—and with Shackleton perhaps experiencing the first symptoms of his later heart trouble—they climbed and slid for 36 hours, stopping only for meals. Shackleton later mentioned that during the march, all three men had had a feeling that there was another person with them; a feeling that occurred independently and was mentioned by them only afterward (Huntford, 1985/1998; Shackleton, 1970). This feeling, which Shackleton interpreted as a mystical experience, was eventually made famous by its representation in T. S. Eliot’s The Waste Land, with its haunting question, “Who is the third who walks always beside you?” (Eliot, 1980, p. 65, lines 359-65).
During the same era of exploration, but in the Arctic, a sensed presence was encountered repeatedly by another explorer whose ship was also trapped, and later crushed, by ice. This was followed by a period of cold and starvation, during which 11 of the 23 non-Inuit crew and scientists died. A passenger and 7 Inuit in the party, the latter including 2 children, all survived (McKinlay, 1977). In this case, the sensed presence was also imbued with religious significance.
In March 1968, Alan Parker, a carpenter working for the Australian Antarctic Division on Macquarie Island, a sub-Antarctic possession of Australia, was alone, building field huts on the island’s plateau. He became disoriented during a storm that saw severe winds blow rain and sleet horizontally into his face (A. Parker, interview with John Geiger, January 19, 2005). Staggering under the full force of the gale, Parker realized he had virtually zero visibility and knew he was in immediate danger. He had his hood pulled down and a balaclava covering his face. He could not establish his orientation in relation to the main camp, and a sense of helplessness overtook him. He then became aware that he had been joined by the presence of another being. “I had the feeling that someone was there with me, saying, ‘Don’t worry, keep going.’” Parker realized it was not a colleague, but something out of ordinary experience. He was not frightened and knew that it was “there to help.” The sense lasted for an hour and a half and receded only when the fierce winds and whiteout conditions abated.
A number of recent examples have also been described, although in contrast to Shackleton and McKinlay, modern explorers tend to attribute the experience to physiological or psychological mechanisms. During his 1998 South Polar expedition, Peter Hillary encountered a sensed presence that he recognized as his deceased mother (Hillary & Elder, 2003). He felt the experience was created by the brain as a coping mechanism: “I didn’t think ‘Where did you come from?’ because I believed it was a projection of what was happening inside my mind” (P. Hillary, interview with John Geiger, October 31, 2005). Sensed presences have also been reported by winter-over parties at Antarctic stations (Suedfeld & Mocellin, 1987).
It should also be noted that the Arctic produced what may be the only malevolent sensed presence experience on record. A dogsled racer participating in a long-distance race, the Yukon Quest, met a colleague on the trail who invited him to rest for a while in a warm and comfortable hotel room. Exhausted, he entered the hotel and went to bed. The next musher on the trail noticed his abandoned sled and dog team, found him sleeping in the snow, and woke him before he died of hypothermia (J. Firth, 1998).
Although mountains, oceans, and the polar regions were the loci of concentrations of sensed presence reports, other dangerous places also evoked reports of helpful and sometimes life-saving apparitions. Three examples will suffice; one is included because it involved a very famous man, a second because it is one of the most harrowing and amazing wilderness survival stories of recent decades, and the third because it involves a man-made disaster, the collapse of the towers of the World Trade Center on September 11, 2001.
Charles Lindbergh, on his history-making solo flight across the Atlantic, sensed “ghostly presences” that passed through the walls of his plane. Although he did not see them, they did speak to him. They kept him company and conversed with him, but also gave him navigational advice and reassurance (Lindbergh, 1953, p. 389).
The second example was that of Aron Ralston. Ralston was hiking through a desert canyon in Utah when a falling boulder trapped his right arm. An experienced mountaineer, he tried everything he could think of to survive and to free his arm, but he was unable to shift or break the rock. Finally, he twisted and broke his arm against the rock so that he could cut it off with the only tool available, a small, dull knife. He then made a makeshift sling for the stump and hiked 10 kilometers (6.25 miles) through the desert before stumbling on some other hikers. He later said that during his worst hours, when he had resigned himself to death, a young boy appeared whom he not only saw but could touch and lift upon his shoulder; a boy whom he identified as his future son, a vision that gave him a reason to survive (Marshall, 2005).
Finally, there is the case of Will Jimeno, a New York Port Authority police officer buried in the concourse level of the World Trade Center when the first of the twin towers collapsed. Ten hours into his ordeal, Jimeno was in poor condition, suffering from injuries and dehydration, when he became aware of a powerful presence with him: “I looked up and saw Jesus coming toward me. He was carrying a bottle of clear, cold water. That moment, I knew we were going to make it out.” Jimeno’s spirits lifted and he felt he would survive; eventually, he was found alive in the rubble (Ellam, 2006).
Explanations of the sensed presence phenomenon abound, which is paradoxical, given the paucity of systematic research on the topic. Perhaps it is the life-and-death drama and the drastic departure from the more mundane paths of experimental and even clinical psychology that intrigues theorists. At any rate, the theories range from the mystical to the psychodynamic, the situational, and the neurological.
We will not attempt to discuss all of these propositions but will sample from each general category.
Perhaps the simplest and most direct explanation is that sensation of a presence is veridical: the sensed entity is actually there. One of the authors, at the end of a presentation about the phenomenon, was challenged by a member of the audience who described herself as one of a large group of people whose astral bodies responded to emergencies around the world, helping those in dire need. In a recent book, Emma Heathcote James (2002) collected stories about sensed presences that were interpreted as guardian angels who saved their beneficiaries from a variety of disasters and misfortunes. Heath-cote James leaves open the question as to whether these angels are real, but does admit the possibility that “other realities” exist. Our answer to angels and traveling astral bodies is the same as that made to the woman whose astral body participated in rescue activities: this is a level of explanation outside the realm of science, and therefore outside our considerations.
Explanations based on psychotic or feverish hallucinations, dreams, and hypnagogic imagery miss some of the crucial aspects of the EUE sensed presence phenomenon. Few, if any, of the perceivers are schizophrenic or in any other way mentally disturbed; there is no evidence of fever in most cases; and most are wide awake at the time of the experience. The temporal aspects of the phenomenon also argue against such theories: it does not last long enough to justify a diagnosis of schizophrenia or any other psychosis. Helpful “lucid dreams” have been reported, but their actual contribution to the person’s physical health or survival is doubtful—unlike the contribution of the great majority of EUE sensed presences.
Concepts involving traumatic or posttraumatic stress have the advantage that the phenomenon certainly appears mostly under conditions that are highly stressful, even when they cannot be justly described as traumatic, for example, Charles Lindbergh’s flight. But the mechanism through which stress results in a sensed presence is not clear, nor is there a good explanation of why some individuals in EUEs experience such a presence while others, perhaps most, in very similar situations do not; and, as usual, the helpfulness of the sensed presence entity is not addressed.
The stimulus monotony-stimulus reduction argument can be formulated as follows. Human beings are evolved for, and through life experiences become accustomed to, a “normal” range of stimulus input and variety. Admittedly, this range is very wide; however, when the level of input is either far below or far above this optimal zone, the information processing system takes steps to move it back into the accustomed range. If there is too much stimulation, there are strategies for ignoring some of it, chunking some of it into fewer units, or masking it in some way; if there is too little, stimulation is generated endogenously through physical and/or mental strategies. In the former, the individual may make noise by singing, humming, whistling, or talking aloud; increase visual stimulation by rapid visual search or, in the dark, pressing ones fingers against ones eyelids to evoke retinal firing; increase tactile stimulation through exercise, biting ones fingernails, stimulating the skin, and so on. To increase stimulation mentally, one may mount an intense memory search, set mental problems and puzzles, make detailed plans for the future, or engage in flights of imagination (Suedfeld, 1980).
The last of these strategies may result in very vivid images that—the theory goes—are sometimes interpreted as being real and existing in the outside environment (Zubek, 1969). The sensed presence may be one form of such externalized imagery. It must be said, however, that even in a profoundly restricted environmental stimulation (REST) situation such as exists in a laboratory, where imagery of various degrees of complexity and in different sensory modalities is common, the images are rarely if ever experienced as prolonged “out-there” percepts. Rather, they are usually quite fleeting and the subject recognizes them as products of his or her own creation (Suedfeld, 1980). Furthermore, there is no recorded example of such images providing any sort of instruction or help to the subject.
Neurological theories come in a variety of interesting forms. Perhaps the most straightforward is the idea that under extreme stress and stimulus reduction, the normally dominant left cortical hemisphere becomes less dominant, reducing the preponderance of logical, linear, reality-oriented thinking. The right hemisphere, which, to put it simplistically, governs creative, imaginative, nonlinear cognition, assumes a greater role than usual; and its products, which may include the perception of an imagined “other,” enter consciousness. REST experiments have supported the hypothesis of a shift in hemispheric dominance (Suedfeld et al., 1994), but, as mentioned above, sensed presences as we have discussed them do not appear in the laboratory. It may be that prolonged high levels of stress, which are contraindicated by the very relaxing laboratory REST environment, are a necessary component for the occurrence of a sensed presence.
A somewhat different hemispheric-shift explanation has been offered by Michael A. Persinger (e.g., 1987, 2001). He stipulated that the sense of self is located in the left hemisphere temporal cortex. Normally, the activity of this area is coordinated with that of the right hemisphere. However, during a seizure or other major event, the two systems may operate in a disjunctive fashion. When that happens, the left hemisphere may interpret signals as “another self,” an out-of-body experience, a near-death experience, an angel, God, or other religious visions, or in our terms, a sensed presence. Which kind of anomalous experience occurs is influenced by the specific circumstances and the individual’s culturally derived and personal belief systems.
Persinger implicates the amygdala as the critical area for such phenomena to occur. According to him, electromagnetic currents, induced or naturally occurring, can alter the neural firing of that organ. When that happens, hemispheric dominance changes as described above, possibly leading to unusual and unexplained experiences, including the sensed presence. Such changes can occur in excessively stimulating environments and those of abnormally repressed stimulation, in agreement with theories based in stimulus impoverishment (e.g., REST). Experimentally stimulating the temporal lobes of the brain with a magnetic field generated in what he calls a “God helmet,” Persinger reported that many subjects sensed “an ethereal presence in the room” (Persinger, 2001, p. 521).
Unlike most theorists in this area, Persinger also acknowledges individual differences in the susceptibility to such phenomena. He suggests that some people’s temporal lobes are more responsive to naturally occurring electromagnetic fields than those of others, explaining why under very similar circumstances some people have the experience while others do not (Selick, 2007).
An experiment in which a specific area of the brain was stimulated with a mild electric current produced unusual phenomena, including something that resembles a partial sensed presence experience (Arzy, Seeck, Ortigue, Spinelli, & Blanke, 2006). In one of two subjects, stimulation of the angular gyrus reportedly led to a feeling that someone behind her was “interfering” with her, lying beneath her on the bed, and hugging her. Most importantly, the sensation disappeared when the current was turned off and reappeared when it was turned back on again. This, of course, is evidence of a causal link that can be obtained only in a laboratory. Because the bodily movements and position of the presence mimicked her own, the researchers concluded that the woman was experiencing a distorted sensation of her own body without realizing it.
This phenomenon did not have all of the hallmarks of the authentic sensed presence experience as we have described it, although some of the latter have been reported to move in conformity to the perceiver’s movements. However, an interesting theory did emerge. According to the researchers, inputs from the sensory receptors and primary sensory regions are integrated to form the full multimodal percept, including feedback from one’s own body. This finding supports one of Persinger’s hypotheses: the integrity of one’s body image can be disturbed if an electric current stimulates the integrative “multisensory” regions of the brain. The question as to whether this is what happens in nonlaboratory sensed presence, and other anomalous experiences, still remains open, however.
Another theory, which is compatible with that of Arzy et al., raises the possibility that “the neurological mechanism underlying the illusion seems to be a projection of postural and kinaesthetic parts of the body scheme into extracorporal space” (Brugger, Regard, & Landis, 1996, p. 114). A more general conclusion is drawn in another paper that suggests, “The hallucination of a ‘sense of presence’ is an example of a broad range of perceptional dysfunctions of personal space and self-position” (Firth & Bolay, 2004, p. 72). How these hypotheses explain the repeated and/or prolonged appearance of a helpful “other” is not clear.
One theory implies an evolutionary origin and purpose for the sensed presence phenomenon (Cheyne, 2001). The argument is that the phenomenon tends to occur during the transition between wakefulness and sleep: hypnagogic (while falling asleep) and hypnopompic (while waking up) hallucinations of a threatening predator. This comes about because a normal state of vigilance aimed at responding adaptively to signs of threat from the environment becomes activated during REM sleep, when the body is paralyzed. This activation may be interpreted as a response to an actual threat, a presence that may be evil or even demonic. However, hypnagogic and hypnopompic states do not last as long as the sensed presence experience frequently does, and usually occur when the person is neither asleep nor paralyzed, for example, during strenuous conscious effort. Even more importantly, the sensed presences of our consideration are almost always benevolent.
A theory that uniquely melds history (and prehistory) with psychology and neurology is the concept of the bicameral mind (Jaynes, 1982). According to Jaynes, prehistoric humans experienced the products of the right cortical hemisphere as external events in the real world. Images and ideas generated by that hemisphere were interpreted as the presence and communication of a god, a spirit, or some other entity; what all of these had in common was access to knowledge and wisdom beyond that of the perceiver. Thus, in works such as The Iliad, advice from friendly gods could save a hero’s life in battle; advice that to us may seem to be common sense, such as Apollo’s recommendation that Hector try to avoid Achilles in single combat.
The bicamerality of the mind diminished and vanished as cultural forces, especially the spread of literacy and, consequently, linear thinking, led us to perceive the processes of both hemispheres as fully belonging to the person, not to outside sources. However, under some conditions, the bicameral interpretation of mental processes can reemerge. Such conditions include early childhood, when not fully literate and acculturated human beings see and hear imaginary playmates; some psychotic states with their visual and auditory hallucinations; fever, when delirium can produce such hallucinations; and situations of extreme stress, when, as we have shown, sensed presence experiences may occur.
Four facts about sensed presences are indisputable: (1) they occur to otherwise mentally normal, physically healthy individuals, many of them adventurous and of outstanding achievement; (2) they occur in stressful situations, prominently including environments of very low temperature and impoverished stimulus input; (3) in almost every case, they serve as a coping resource in that they aid the individual’s efforts to survive; and (4) despite a proliferation of theoretical explanations, the critical studies that would enable us to choose among these remain to be conducted.
Because the phenomenon is so striking, and because some of its aspects are not adequately explained by any of the theories, it is clear that the sensed presence experience will continue to intrigue both mass audiences and scientists for the foreseeable future. Above all, perhaps, is the need to understand the dramatic helpfulness of the sensed presence, which includes not only encouragement but also factual information such as navigational directions and, on occasion, physical intervention. The only theory that has anything to say about this is Julian Jaynes’s; but the mechanism through which bicamerality emerges in modern human beings to serve as a resource, as it did in antiquity, needs empirical testing and more detailed explanation.