The haunted brain

 Not our houses but our brains are haunted. (G.M. Beard, 1879)

Neuroscience will one day provide explanations for what most people call ‘paranormal’ phenomena. These are more accurately described as anomalous psychological experiences, and are broadly defined as those experiences which cannot be accounted for using conventional scientific explanations.

We can (and should) deny the existence of ghosts and UFOs. Phenomenologically, however, the paranormal experiences of individuals are very real. Paranormal phenomena are altered states of consciousness brought about by changes in the electrochemical activity of the brain.

As will become clear below, some of the subjective experiences of these individuals can be explained in neuroscientific terms. It will eventually be shown that all paranormal experiences are neurogenic in nature – that is, they originate in the brain and its activity. Some of these phenomena, such as hauntings, can be explained by patterns of brain activity; others, such as ‘automatic writing’, can be explained by certain neuropsychiatric conditions. Paranormal belief systems are associated with particular personality characteristics, and some paranormal phenomena have their basis in psychopathology.

Belief in paranormal phenomena is an example of ‘magical thinking,’ or non-scientific causal reasoning. Magical thinking has several elements, such as believing in the interconnectedness of all things through forces that transcend the physical world, investing symbolic objects with special powers, and making causal connections between seemingly unrelated events.  

Psychologists have studied paranormal (or ‘psi’) phenomena in some depth but the field of parapsychology remains controversial within the mainstream scientific community. Most scientists regard parasychology as a pseudoscience,  because it leads us towards superstition and magical thinking, whereas the ‘real’ sciences move away from them. The  standing of parapsychology among scientists is not helped by the mysticism surrounding these phenomena, or the large number of fraudsters, incompetent researchers and hoaxes associated with the field.  

Despite this, paranormal beliefs are hugely popular and widespread. This is reflected in the success of television programmes like The X Files. According to a Gallop poll conducted last year, 75% of Americans have some kind of paranormal belief, and a Daily Mail poll (2nd Feb. 1998) put the figure of British people with such beliefs at over 60%.

There is a huge diversity of psi phenomena; below is a list of some of the more common ones.

  • astrology
  • belief in UFOs
  • clairvoyance  
  • extra-sensory perception (ESP)
  • facilitated communication (e.g. ‘automatic writing’)
  • out-of-body experiences
  • precognition/ premonitions
  • poltergeist hauntings
  • telekinesis
  • telepathy

This list is by no means exhaustive, and I will only try to explain a few of them in terms of neurobiology.

Individuals who report experiencing psi phenomena are known to have certain personality characteristics. It is found, for example, that people with paranormal beliefs more readily make associations between unrelated words or events than do people without paranormal beliefs. They are also more creative and prone to fantasy than others.

People who have paranormal experiences may also be prone to visual and auditory hallucinations. Schizophrenics, and, to a far lesser extent, ‘normal’ people, experience auditory hallucinations. These ‘voices’ are known to be generated by the brain, but those who experience them deny that they originate from there, even though neuroimaging studies have shown that the voices are generated by activity in the neuronal circuits normally associated with speech production.

All psi phenomena include a blurring of the distinction between perception and imagination; many involve reports of a sensed presence and distortions in the perception of time. Claims of experiencing the presence of ghosts or spirits are particularly common. Many alleged sightings of ghosts take place in specific places and are usually associated with loud noises, strange smells and apparitions.

It is well documented that patients with temporal lobe epilepsy often report having paranormal or religious experiences. In fact, both kinds of experiences can be evoked experimentally by magnetic stimultaion of the temporoparietal region. These regions, which are involved in awareness of the ‘self’, trigger the experience of a sensed presence when stimulated.

Michael Persinger, a professor of neuroscience at Laurentian University in Ontario, Canada, was the first to suggest that electromagnetism can affect brain activity, and has evoked spiritual and paranormal experiences in people in this way. Persinger believes that brain activity can explain anything that might be described as a paranormal experience, including apparitions, aliens, near-death experiences and past-life sensations.

It seems very plausible, then, that claims of ghost sightings can be explained in terms of magnetism. A ‘haunted house’ may be located in an area with a particularly strong geomagnetic field, or one which is prone to large fluctuations in its geomagnetic field. This would alter the temporal lobe activity of people entering the area, evoking in them the experience of a sensed presence, or a ‘ghost’.

Automatic writing (or ‘trance’ writing) is a form of facilitated communication involving the production of written material which is alleged to come from somewhere other than the conscious thought of the writer, and is another phenomenon frequently used as evidence of the existence of ghosts or spirits. It is frequently claimed that the written material is being produced by a spirit from another world who has temporarily possessed an individual’s hand or arm in order to communicate.

A precursor to facilitated communication is the famous case of Clever Hans, a horse trained by the retired schoolteacher Wilhelm von Osten. Around the beginning of the twentieth century, von Osten claimed that his horse could count, read and respond to simple yes or no answer questions, becoming an international celebrity as a result. For example, when asked by von Osten to calculate 7 times 3, Clever Hans would gently pat his paw on the ground 21 times.

The claims by von Osten that Clever Hans could actually count and read were soon discredited. It soon became evident that, rather than having a real understanding or an ability to communicate, the horse was responding to subtle visual cues provided by von Osten with simple motor behaviours. von Osten, however, always denied that he had conditioned Clever Hans to perform movements in response to specific cues; i.e. von Osten was denying ownership of the movements he performed and to which Clever Hans responded.

Certain neuropsychiatric conditions are known to produce symptoms of the denial of ownership of one’s motor behaviours. This involves a breakdown in the link between one’s behaviour or experiences and the awareness that one is an agent who is responsible for those behaviours.

Somatoparaphrenia, or delusional beliefs about one’s own body, such as the ownership of a limb by another person, is a condition that can be caused by right hemisphere stroke or other types of damage to the brain. It is also relatively common in schizophrenic patients. Somatoparaphrenic patients typically think that a paralyzed limb belongs to their docotr or spouse; this is sometimes accompanied by complex hallucinations.

‘Alien hand syndrome’ is a similar condition in which the ownership of motor behaviours is denied. Patients exhibiting alien hand sydrome have a partial disconnection of the anterior corpus callosum, the bundle of one hundred million fibres connecting the two hemispheres of the brain. One phenomenon that might be explained by alien hand syndrome is the ouji board. Psychics claim that during seances they can use ouji boards to communicate with the spirits of deceased people. It is likely that the board is actually being controlled by the psychic, who will, of course, deny this vehemently.

Alien hand syndrome is also demonstrated by split brain patients. These are epileptics who have had commissurotomies (severing of the corpus callosum) to prevent the spread of epilepsy from one hemisphere of the brain to the another. The commisurotomy is a drastic procedure that was used in patients with severe, untreatable epilepsy.

Amazingly, split brain patients behave completely normally most of the time. Only under experimental conditions do the bizarre effects of their surgery become evident. Roger Sperry and Michael Gazzaniga conducted classic experiments on split brain patients in the 1960s.

In one set of experiments, patients sat at a table with a screen attached to it. Under the screen were various objects which the patients could feel but not see. Patients were asked to pick up objects and describe them. When patients picked up an object with their right hand, the tactile information about that object is transmitted to the left hemisphere, which contains the speech centres, and the patient is able to name the object. If, however, the patient picks up an object with the left hand, the same information is processed by the right hemisphere. Because the connections between the two hemispheres have been severed, the information about the object cannot be transmitted to the speech centres in the left hemisphere, and the patient cannot name the object.

Occassionally, split brain patients behave bizarrely in normal situations. When dressing, for example, they have been known to choose a garment of clothing with one hand, only to snatch it and throw it back into the wardrobe with the other!

Why do split brain patients behave in this way? First, there is contralateral control of the body by the brain. The left hemisphere controls and recieves information from the right side of the body, and vice versa. That there is a localization of brain function, with the left hemisphere specialized for certain functions and the right for others, has been known for a long time.

The study of split brain patients clearly shows that the two hemispheres of the brain control different aspects of thought and action. The process of disconnecting the two hemispheres of the brain bifurcates the the mind. The split brain patient sometimes behaves as if they have two minds, or as if there are two different people inhabiting the same body. The two hemispheres of the brain produce different aspects of consciousness which are normally unified. This unity is sometimes lost in the split brain patient. In the words of Sperry, each hemisphere constitutes “two separate realms of conscious awareness; two sensing, perceiving, thinking and remembering systems.”

Undoubtedly, as our understanding of brain function increases, the neurosciences will provide explanations for more of these phenomena, and advances in consciousness studies, combined with quantum physics, may one day explain others. A paranormal experience, like a religious one, is an altered state of consciousness. To gain an understanding of these altered state of consciousness is to better understand the nature of consciousness itself.

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7 thoughts on “The haunted brain

  1. For those more interested in the science and psychology behind paranormal phenomena, Mary Roach’s book ‘Spook’ provides an entertaining account of her quest for ‘proof’ of the paranormal. Perfect for former parapsychology junkies turned cognitive neuroscientists such as myself.

  2. Since I got here from the skeptics’ circle, I expected the site would promote skeptical thinking, not its opposite.

    Persinger’s celebrated ideas mix fact and fiction in a way very detrimental to strict reasoning. It is true that the brain can enter altered states of consciousness and that many religious and spiritual feelings or thoughts can be attributed to neurophysiological causes, but to suggest that these states can be triggered by environmental electromagnetic fields is a claim he certainly has not tested, and which probably can’t be tested with existing technology. A more likely explanation for believing a house is haunted than some geo-physical aberration, is that the person who thinks so is disposed for personal or cultural reasons to believe that a house can be haunted. To demonstrate Persinger’s claim one would have to find a place where people who don’t believe in ghosts consistently report seeing them. You would have to search a long time for that.

    As for automatic writing—a celebrated and as far as I know typical case involved the poet W. B. Yeats.

    1. he believed that his wife was a medium who channeled some kind of higher spiritual truth through automatic writing.

    2. he did not want to have children.

    3. His wife did want to have children.

    4. Eventually his wife’s automatic writing advised him to have children.

    Does this really need explanation? If you don’t understand what was going on, go look at the Dream sequence in Fiddler on the Roof.

  3. Helena,

    I agree that cultural conditioning has a large part to play in paranormal beliefs and experiences, but we cannot dismiss the possibilty that geomagnetism might affect brain activity.

    Skeptics may experience an altered state of consciousness when entering a ‘haunted house,’ but they would be less likely to attribute it to the existence of ghosts than would someone more inclined towards paranormal beliefs.

    I am not, and do not claim to be, an expert on the cognitive neuroscience of paranormal phenomena; I merely tried to explain them in scientific terms. I have contacted Dr. Persinger and asked him to respond to your criticisms of his work. His response will be posted here in the near future.

  4. Its preposterous to conclude that paranormal phenomena are products of electromagnetic activity in the brain. There has never been any conclusive evidence for this deduction.

  5. auditory hallucinations, spatial location and paranoid delusions

    Could this be a very important thing; if you type in the words “people talking” and “auditory hallucinations” in google, you will find that many voice hearers believe that other people/neighbours etc are talking about/persecuting them (and this often leads to violence) – before they find out that they are hearing voices. We know that voices can be heard both inside and outside of the head; could it be that the truth is more nuanced, and that the voices can also be heard to emanate from people’s lips, passing cars, from MULTIPLE locations outside of the head (in external space).

    I have been reading some material about delusions of reference in schizophrenia, i.e., the idea that some people have that the t.v. or the radio is talking about them and would like to propose that just as people hear auditory hallucinations internally and externally, for some reason, they may hear auditory hallucinations coming from a t.v or a radio. I suspect that certain areas of the brain that register the spatial location from where a sound emanates is activated when people hear voices from a radio or a t.v. I wonder whether people who think that other people are talking about them also hear voices emanating from the spatial location of the other person/persons.

    I would like to quote a passage from one of the articles of Ralph Hoffman (Acta Psychiatr Scand, 2006) “Seeing Voices”: fused visual/auditory verbal hallucinations reported by three persons with schizophrenia-spectrum disorder” – “A male patient reported AVHs consisting of male and female voices occuring at a rate of 7-10 times per hour. He also reported visualizing lip and mouth movements superimposed on otherwise veridical perceptions of faces of actual persons that were fused with (i.e., matched the verbal content of and occurred in synchrony with) simultaneous AVHs. These fused visual/auditory hallucinations occurred most frequently when the patient was in the presence of his family or other familiar persons, and tended to reinforce the patient’s conviction that others in his immediate environment were the source of the ‘voices’ he heard.”

    There is an article from Scientific American that shows how barn owls locate sounds in space (Listening with two ears, Scientific american, 2006) There also seems to be some research on the internet on how the human brain locates the spatial location from where sounds emanate. I wonder whether schizophrenia researchers would be able to use scientific techniques to see which regions of the brain are activated when people think that they are hearing voices from the radio or the t.v.

  6. I was a staunch Atheist and non-believer in ghosts. Until a friend visited me before I knew he was dead. Undeniable experience. I’ve told hundreds of it. 50% of them have had their own experience of a visit from the not known yet to be dead.

    The Chinese philosopher, Mo Tzu (470-391 BC), is quoted as having said:
    “The way to find out whether anything exists or not is to depend on the testimony of the ears and eyes of the multitude. If some have heard it or some have seen it then we have to say it exists. If no one has heard it and no one has seen it then we have to say it does not exist. So, then, why not go to some village or some district and inquire? If from antiquity to the present, and since the beginning of man, there are men who have seen the bodies of ghosts and spirits and heard their voices, how can we say that they do not exist?

    We know that most of the universe we know very little about. Dark matter/energy is over 95% of its mass and all around/through us. Anyone gonna claim it has no order?
    What kind of skeptic or scientist claims something doesn’t exist with no proof?
    Shall we claim the majority of humanity are just delusional because we don’t yet have all the mechanisms dismantled?
    Good luck boys. Hope you can laugh at your fleshcalcs absurdity when your time comes to leave it.
    Lol’s

  7. We know that most of the universe we know very little about. Dark matter/energy is over 95% of its mass and all around/through us. Anyone gonna claim it has no order?
    What kind of skeptic or scientist claims something doesn’t exist with no proof?
    Shall we claim the majority of humanity are just delusional because we don’t yet have all the mechanisms dismantled?
    Good luck boys. Hope you can laugh at your fleshcalcs absurdity when your time comes to leave it.
    Lol’s

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