Dec 23 2008
Who Goes There?
Have you ever had the sense that you were not alone, that another person, perhaps menacing, was in the room with you? And yet, when you look around, no one was there? This is a common experience, which researchers call a “sensed presence.” Neuroscientists hypothesize that this common experience likely has a neurological correlate – meaning that activity in some specific part of the brain is responsible for generating the sensation of a presence.
So far, research has validated that hypothesis. And recently the research team of Michael Persinger had the fortune of capturing a sensed presence event on EEG (which measures the electrical activity of the brain).
The subject is a woman who has had numerous episodes of sensed presence after a head injury. Persinger now presents a case report of her EEG, recorded while she experienced the sense of a man in the room with her when none was present. For some reason as yet unknown, 90% of time a sensed presence is of a member of the opposite sex. The EEG shows a burst of electrical activity in her left temporal lobe during the event, and of note she perceived the presence to be on her right side. (Brain activity corresponds to the contralateral or opposite side of the world.)
This confirms prior evidence. Persinger previously published evidence showing that the incidence of a sensed presence could be manipulated in subjects by using transcranial magnetic stimuation. When applied to both temporal lobe or the right temporal lobe the incidence was greater than when applied to only the left temporal lobe or when a sham stimulation was done as a control. He postulates that perhaps a sensed presence occurs when there is a glitch in the communication between the two temporal lobes.
Persinger with another researcher, Tiller, showed that induced sensed presences tend to occur opposite the side of the brain being stimulated, as with the subject in this recent case report.
Persinger and another lead author, Cook, were able to induce the experience of a sensed presence in 9 of 15 volunteers in another experiment using magnetic stimulation. Of interest, one of the subjects had a history of “psychicaly” reading medical diagnoses from photographs. They reported that they would get flashes of visions in their left upper visual field. Cook and Persinger document that they were able to increase the frequency of these experiences by applying the magnetic stimulation in a blinded fashion. They also document that when a subject tries to look at or focus on the location of the presence it moves or evades their gaze.
This line of research has significant implications for anyone interested in the paranormal or mystical experiences. The experience of sensing a presence that is not physically there often triggers mystical interpretations – as is likely what happened with the “psychic” subject in the previous study. Often times the presence is given divine significance. Most people assume that whatever they experience is real (especially if are not intoxicated or if there is no other simple explanation at hand). They therefore will make sense of their experiences within their belief systems or world view. We see this happen also with the phenomenon of hypnagogic hallucinations (waking dreams), which in the past have been interpreted as demonic visitations but recently are more likely to be seen as alien abductions.
Persinger also showed that low level magnetic fields may induce the experience of a sensed presence. He postulates that geological activity, which can generate these low level magnetic field, may be responsible for mass hallucinations in areas with a lot of activity. Or at least increase the incidence of experiencing a sensed presence.
The understanding that our brains are electrochemical machines, albeit highly complex ones, liberates us from grasping at mystical explanations for brain-derived experiences.
25 Responses to “Who Goes There?”
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It’s really fascinating how much we can learn from brain injuries.
How long will it take for Egnor to comment on this study? Will he Egnor it?
I wasn’t aware of Dr. Persinger’s new research, it sounds interesting.
I don’t know if you are aware, but many researchers have expressed doubt in his earlier research into stimulating sensed presence using TMS.
We discuss it on our podcast here
A direct link to the failed replication study is here
As I say in the podcast, I think this is a great case where some scientific research would support the skeptics’ position, but which skeptics should still be doubtful of due to failure to replicate, and other problems. I’m interested in hearing your opinion on this issue, since you’re obviously more qualified than we are to judge the science.
Looks like the link to our podcast didn’t work, let’s try this link instead. Apologies for the double post.
Yeah – the results need to be replicated by more researchers before the final word is in. But I think Persinger’s research shows that there is a component of the experiences that can be manipulated and determined by magnetic stimulation – not just suggestion or prior belief, as some of the critics have charged. There is probably an element of these as well – it takes tight protocol to separate these factors.
Here is a recent review by Persinger to answer his critics: http://www.ncbi.nlm.nih.gov/pubmed/16861170?ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.Pubmed_Discovery_RA&linkpos=1&log$=relatedarticles&logdbfrom=pubmed
What I find particularly compelling is that the sensed presence can be made to occur on the opposite side of the brain being stimulated. Assuming this data is reliable, that strongly suggests a biological and not psychological cause.
“Have you ever had the sense that you were not alone, that another person, perhaps menacing, was in the room with you?”
Yeah, it’s called MARRIAGE.
I used to frequently experience sleep paralysis when I was younger, and while I was paralyzed I often would feel that there was a presence in the room with me. The presence was always a female(I am male), which matches with what you are describing here.
Maybe I am missing something, but I don’t see how finding a brain derived experience that resembles a described “mystical” or “paranormal” experience proves that these phenomena don’t exist. Could not one claim that stimulating a portion of the auditory cortex yields an experience of hearing music demonstrates that orchestras do not exist.
Isn’t this a logical fallacy?
I love learning about things like this so that if someone tells me that they knew there was someone in the room I can give them a little neuroscience lesson
Thanks for blogging this, Steve.
Perhaps this is just because I’m far too enamored with evolutionary psychology, but I’ve long wondered whether a ‘sensed presence’ isn’t an adaptation (that sometimes goes awry). Clearly, an undetected agent behind you could be seriously fitness reducing, and if there is sensory information about such a presence that is not consciously accessible (analogous to the phenomenon of blind sight, say), then that feeling that someone’s behind you or ‘looking at you’, may be the result. Obviously, I’m not suggesting anything paranormal here — simply that our spooky ‘someone-is-behind-me’ sense may be straightforward adaptation that works ‘subconsciously’.
What do you guys think?
I had this as a side effect to some medicine I was taking for terrible GI pain. I had the constant feeling that someone was just over my right shoulder, and I couldn’t concentrate on my work as a result.
Luckily I work with some Toxicologists who recognized right away what was happening, and they sent me home. I decided intense belly pain was better than such a bizarre feeling, and ceased the medication immediately.
What surprises me is that people still believe this is supernatural. Since we can induce such symptoms, wouldn’t that by definition eliminate the possibility that such “premonitions” are supernatural?
“What surprises me is that people still believe this is supernatural. Since we can induce such symptoms, wouldn’t that by definition eliminate the possibility that such “premonitions” are supernatural?”
Advocates of the supernatural would merely tell you that it’s like a magician’s trick, that just because a magician can induce a paranormal appearing event doesn’t mean the event can’t occur ‘paranormally’. Like UFO advocates, every time you debunked a given sensory event, they’d just say, ‘well, yeah, that one was natural, but we have all these other unexplained ones..’
They’ve developed ad hoc ‘outs’ for just about everything.
MichaelE,
You are correct, it is a fallacy.
I wanted to clarify that I am not a paranormal advocate. Just that I don’t find the argument sound.
I had a patient who was very disturbed by very vivid visual hallucinations of demons living inside her. To compound it, some preacher had told her that they were real, punishment for her sins. Her arms were covered with scars from trying to scrape them out. She slowly improved with high doses of antipsychotics. The demons slowly changed from being inside her, to being outside her, glaring and mocking her. Eventually they were only in the distance, but even after months she would see them in mirrors.
She struggled with the question of their reality. She would say “they seem so real, but there must be something to what you say, because the medications clearly work.”
MichaelE: “strongly suggests” is not the same as “proves” which in turn is clearly not the same as “demonstrates.”
Which begs the question that if you are deemed correct, what is the fallacy that you are correct about?
MichaelE may be referring to the fallacist’s fallacy, the errant assumption that because an assertion is based on faulty argument, the assertion must be false. In fact, the assertion may be true – it just isn’t established by the faulty reasoning.
Thanks DevilsAdvocate,
That is indeed what I was trying to get at.
I think I just saw the two wrongs make a right fallacy fly by with a big grin on its face
MichaelE
You are correct – but I have to point out that I never wrote that this research, assuming it is confirmed, proves that paranormal experiences don’t exist. Nor did any of the studies I linked to. What even prompted you to point that out?
What it does do, however, is possibly establish a neurological cause for such experiences. This removes the need to hypothesize an entirely new phenomenon to explain them.
Your analogy to orchestras is also not apt. Finding a neurological correlate to an experience of a sensed presence does not mean that real presences (actual people being present) do not exist. That would be analogous to your orchestras. Likewise, the ability to generate the experience of hearing music from external magnetic stimulation might mean we don’t have to hypothesize that there are phantom orchestras playing music to explain the experience of hearing music in the absence of a physical source of music.
@MichaelMeadon
“Clearly, an undetected agent behind you could be seriously fitness reducing, and if there is sensory information about such a presence that is not consciously accessible (analogous to the phenomenon of blind sight, say), then that feeling that someone’s behind you or ‘looking at you’, may be the result. Obviously, I’m not suggesting anything paranormal here — simply that our spooky ’someone-is-behind-me’ sense may be straightforward adaptation that works ’subconsciously’.
What do you guys think?”
I seem to remember some work done back in the 1980′s which I looked at during my undergrad’ psychology. Much of it was about “fear of the dark” and how this could be an “adaptation to nocturnal predation”, by ancestors that got regularly pounced on in the dark. There was also some theorising on what I think they termed “phantom presence”.
This was a loooong time ago and I’m not sure I have any of that stuff accessible now, but I’ll do a bit of “poking around”.
I think fear of the dark may be further reduced as one form of fear of the unknown, and when in the province of predators, it may have been profitable to be wrong about it 100 times to save oneself once.
I also wonder if there isn’t a cognitive ‘zone’ between the subconscious and open, alert awareness, that is, perhaps when I get that seemingly intuitive feeling that something or someone is behind me, I’m reacting to a mundane stimulus observed in the usual way(s), but it’s such a minor thing it registers only very very briefly in my awareness; I’m barely conscious of it. Perhaps a squirrel high in the tree has dropped a nut shell into the dry leaves on the ground behind me, it spooks me, I turn around to find no danger. My hearing the nut shell fall having not registered in my memory, I confabulate some mystical explanation for the sensation.
I’d like to thank all posters, btw, for not citing the, ahem, work of Rupert Sheldrake on this topic.
Paul… Yeah, I’ve seen similar sounding work on the fear of the dark. As I recall, the developmental sequence fits nicely into an evolutionary perspective: just like children start fearing strangers when they’re more independent of their mothers, it seems the fear of the dark develops when children are likely to start wondering off. I haven’t read this literature properly, though, so I have no idea whether it’s been done rigorously or whether some hack just threw together a just so story…
Devils… it’s a pity pseudoscientists like Sheldrake have muddied the waters in this area. I think a bunch of cool (actually scientific, non-paranormal) work is just waiting to be done, but the paranormalists have tinged the whole field, it seems.
Novella:
Egnor, two weeks later:
And no, I’m probably not being facetious.
@MichaelM…
Evolutionary psychology, I’ve always thought, was (for the most part), just so.
I doubt Persinger’s work is appropriate for a science blog.
His work has been studied and there have been attempts to replicate them.–
http://dx.doi.org/10.1016/j.neulet.2005.03.059
From the article-
Larsson et al. (the authors) go into great detail explaining how their conditions replicate those of Persinger. Here is a choice quote:
“Regarding double-blindness, which we believe to be the most important reason for the different results between our laboratories, we have not read all of the several hundred articles published by Persinger in this and related areas. However, we have carefully checked the methodological descriptions of the studies that were cited in the response by Persinger as representing truly double-blind procedures. As far as we can judge, none of them was double-blind according to the conventional definition of the term…”
Persinger fails to use a double-blind procedure. His responses to the critics are not meaningful.
Until Persinger does a real experiment under scientific conditions and stops making claims about his earlier work, I think he can be deemed an unreliable source for scientific information.
(It is easy to get atheists and newspaper writers all excited about the prospect of a ‘god helmet’ (certainly many famous skeptics fell for it), but we don’t need to make that mistake.)
There are all kinds of stories about a sensed presence. I don’t think a person who has a religious belief against the possibility of that presence existing as an entity (a ghost or spirit, if you will) is qualified to make a scientific determination regarding what that presence might be. Atheists and materialists have such a religious faith.
(Illogical- begging the question)