GHOST-HUNTING - Paranormality - Richard Wiseman

Paranormality: Why We See What Isn't There - Richard Wiseman (2011)


In which we spend some quality time with an old hag,
discover why poltergeist researchers once shook a house
to pieces, meet the non-existent phantom of Ratcliffe
Wharf, learn how to see a ghost and explore
the psychology of suggestion.

There is an old joke about a University lecturer who asks his class, ‘Has anyone here ever seen a ghost?’ Fifteen students put their hands in the air. Next, the lecturer says, ‘Well, who here has touched a ghost?’ This time only five hands go up. Curious, the lecturer adds, ‘OK, has anyone actually kissed a ghost?’ A young man sitting in the middle of the lecture theatre slowly raises his hand, looks around nervously and then asks, ‘I’m sorry, did you say ghost or goat?’

Thankfully, the results from national surveys have yielded more clear-cut findings. Opinion polls from the past 30 years or so have consistently shown that around 30 per cent of people believe in ghosts and that about 15 per cent claim to have actually experienced one.1 Additional questioning has revealed that these alleged ghostly encounters do not involve white-sheeted figures drifting through walls, women in black bringing death and destruction, skeletons prancing through cemeteries or headless knights clanking their chains. Despite the frequent appearance of such images in ghost stories and horror films, actual apparitions are far more mundane.

A colleague of mine, James Houran, has carried out a great deal of research into the nature of these ghostly experiences. James is an interesting fellow. During the day this mild-mannered statistician works for a well-known internet dating site creating mathematical models that help promote compatibility. By night Houran transforms into a real life ghost-buster, conducting surveys and studies that aim to solve the mystery of hauntings. A few years ago he analysed almost a thousand ghostly experiences to discover what people report when they believe that they have encountered a spirit.2

Houran’s work revealed that reports of fully fledged apparitions are very rare. In fact, they only account for 1 per cent or so of sightings and when such figures do turn up they usually appear at the foot of a bed as people are either waking up or drifting off to sleep. Such apparitions have an uncanny knack of looking like a normal person, and their ghost-like nature only becomes apparent when they do something impossible, like suddenly vanish or walk through a wall.

So if people are not seeing full apparitions when they encounter a ghost, just what do they experience? Around a third of Houran’s reports involve rather fleeting visual phenomena, such as quick flashes of light, odd wisps of smoke or dark shadows that move furtively around the room. Another third involve strange sounds, such as footsteps from an empty room, ghostly whispering, or inexplicable bumps and knockings. The remaining third are a mixture of miscellaneous sensations, including odd odours of flowers or cigar smoke, sensing a ghostly presence, feeling a cold shiver down the spine, doors opening or closing of their own accord, clocks running especially fast or slow, and dogs being unusually noisy or quiet.

For well over a century scientists have attempted to explain these strange experiences. Some firmly believe that their investigations provide compelling evidence of life beyond the grave. Others are equally convinced that these seemingly supernatural sensations have down-to-earth explanations. Their experiments involve an odd mixture of ground-breaking dream research, camping out in haunted houses, vibrating fencing foils, sitting in the dark waiting for God, shaking entire buildings until they fall to pieces and staging large-scale hoaxes.

Our journey into this mysterious world begins with perhaps the most widely reported of all ghostly experiences.

Henry Fuseli and his Emotionless Horse

In 1781 the Swiss oil painter Henry Fuseli created his most famous work. Entitled The Nightmare his painting depicts a woman having a terrible dream and the content of her frightening experience. The woman is sound asleep, lying on her back and with her head hanging down from the edge of her bed. A small evil-looking demon sits on her chest and peers out from the canvas. Towards the back of the painting a horse’s head with emotionless eyes is seen emerging from a curtain and staring menacingly at the woman.

The Nightmare proved an instant hit when it was first exhibited at London’s Royal Academy, quickly achieved worldwide acclaim, and now features on the cover of almost every academic textbook about the paranormal. Fuseli created another version of the painting several years later, but it is generally agreed that this painting lacks the emotional impact of the original, in part because the demon appears to be wearing a Batman mask and the horse looks like it has just won the lottery.

Fuseli’s painting depicts perhaps the most frequently experienced of all ghostly encounters; the arrival of the incubus. According to legend, the incubus is a demon who adopts a male form and forces itself upon sleeping women using its unusually large and cold penis (the Arthurian wizard Merlin was allegedly the result of such an encounter). Sitting on the chest of their victim to prevent movement, the incubus goes about its beastly business while other equally demonic creatures stand by the bedside watching. Never ones to miss an opportunity, it is said that such demons can also take the form of a female succubus and seduce sleeping men (albeit presumably without the aid of an unusually large and cold penis). These creatures have been reported in many different cultures. In Germany the demon is referred to as the ‘mare’ or ‘Alpdruck’ (‘elf pressure’), in Czechoslovakia they are the ‘muera’, and the French call them the ‘cauchemar’.

Although it is easy to believe that nocturnal demonic experiences could have been the height of supernatural sophistication when Fuseli created his paintings, surely they are not still alive and well in the 21st century? In fact, recent surveys suggest that around 40 per cent of people have experienced exactly the same sensations, including waking up and feeling a crushing weight on their chest, sensing an evil presence, and seeing strange figures in the darkness.3 These episodes are often interpreted as evidence of demons, ghosts, or even an alien abduction. Regardless of the way in which they are perceived, one point is quite clear - even to the modern mind they are a terrifying and unforgettable experience.

For centuries many of those who have come face to face with night-time demons have been convinced that they have encountered hell on earth. It is only in the last fifty years or so that research has revealed the remarkable truth behind these apparitions.

The Incurably Curious Eugene Aserinsky

The year 1951 did not start well for University of Chicago psychologist Eugene Aserinsky.4 At work, his post-doctoral research into the eye movements of sleeping babies was proving both slow and unrewarding. At home, Aserinsky was facing severe financial difficulties. His family were forced to live in a small, cold apartment and he could only just afford to rent the typewriter that he needed to write up his work. Years later he described the sense of desperation that he faced:

If I had a suicidal nature, this would have been the time. I was married and had a child. I’d been in universities for twelve years with little to show for it. I was absolutely finished.

In addition, he was exploring avenues that simply didn’t interest his more mainstream colleagues. The vast majority of academics at the time assumed that the brain switched off when people drifted into the land of nod and turned back on when they woke up, and didn’t share Aserinsky’s interest in the psychology of sleep. However, Aserinsky wanted to discover if this ‘move on, nothing to see here’ approach to the sleeping brain was correct. Unable to attract proper funding for his work, he found an old brainwave measuring machine (referred to as an ‘electroencephalograph’) in the basement of his department, dragged it up into his office and managed to get it working. Unfortunately, one major problem remained - without proper funding who would be willing to spend several unpaid nights in Aserinsky’s sleep laboratory covered in sensors? Eventually he managed to come up with a lateral solution to this problem as well. On a cold evening in December 1951 he tucked his eight-year-old son Armond into the laboratory bed, connected eye movement and brainwave sensors to Armond’s face and head, and retreated to his office.

After an hour or so, Armond drifted off to sleep and the experiment began. For the first 40 minutes or so Aserinsky carefully monitored the pens tracing the output from the electroencephalograph. The lack of movement was underwhelming, and it looked like the scientific establishment had been right to let sleeping brains lie. About 20 minutes later the pens started scribbling away, indicating large amount of activity from both the eye movement and brain activity sensors. Assuming that his son had woken up, Aserinsky went to check that he was okay. When he opened the door to his laboratory, he couldn’t believe his eyes. His son was sound asleep.

At first Aserinsky assumed that his experimental equipment was faulty and set about checking the large number of leads going in and out of the electroencephalograph. No obvious problems emerged. The following day he showed the charts to his supervisor who also thought that there must have been a problem with the equipment, and asked Aserinsky to run a second set of more thorough checks. The system came back with a clean bill of health. A few more nights of monitoring Armond in the sleep laboratory convinced Aserinsky that his findings were genuine. At certain points during the night the sleeping brain became mysteriously and amazingly active. Additional work revealed that these sudden rushes of brain activity were accompanied by rapid eye movements or, as Aserinsky referred to them, ‘REMs’ (he originally wanted to call these ‘jerky eye movements’ but was worried about the negative connotations of the word ‘jerk’). Not only that, but whenever Aserinsky woke a participant up after a period of REM the person almost always reported a dream.

In September 1953 Aserinsky and his supervisor published their findings in a now-classic paper entitled ‘Regularly Occurring Periods of Eye Motility, and Concomitant Phenomena, During Sleep’, and changed psychology for ever.5 Suddenly researchers realized that there was a great deal more to the sleeping brain than they had previously assumed, and that Aserinsky had discovered a way of entering the hitherto hidden world of dreaming. As one researcher later remarked, it was like discovering ‘a new continent in the brain’, and scientists across the world were suddenly eager to explore this brave new world. Strangely enough, Eugene Aserinsky didn’t join them. Ever the unconventional but incurably curious polymath, he left the University of Chicago soon after his ground-breaking experiment to investigate the effects of electrical currents on salmon.

To Sleep, Perchance to Dream - Ay, There’s the Rub

Researchers have now identified five distinct stages of sleep.

Soon after nodding off you drift into the creatively labelled ‘Stage 1’. Here your brain is still very active and producing high frequency brain waves known as ‘Alpha’ waves. During this stage people frequently experience two types of hallucinations known as hypnagogic imagery (which occur when people are drifting into sleep) and hypnopompic imagery (which occur when they are waking up). Either type can result in a wide range of visual phenomena, including random speckles, bright lines, geometric patterns, and mysterious animal and human forms. These images are often accompanied by strange sounds such as loud crashes, footsteps, faint whispers, and snatches of speech. Interestingly, these are exactly the type of experiences that have been mistaken for the presence of a ghost for hundreds of years.

Having survived the potential terrors associated with ‘Stage 1’ you drift into ‘Stage 2’. Again, your brain is far from calm, often producing brief bursts of activity known as ‘spindles’. ‘Stage 2’ lasts for about 20 minutes and can result in the occasional mumble and even full on sleep-talking. Slowly you drift further down into, you guessed it, ‘Stage 3’. Now your brain and body are starting to become properly relaxed and after another 20 minutes or so you finally enter the deepest stage of sleep … In ‘Stage 4’, your brain activity is at a minimum, resulting in very slow moving ‘Delta’ waves. If you are going to engage in a spot of bedwetting or sleepwalking, this is the moment.

After around 30 minutes or so in ‘Stage 4’ something very strange happens. Your brain moves rapidly back through the first three stages and then enters a mysterious state. It exhibits the same high levels of activity originally displayed during ‘Stage 1’, but your heart races, your breathing becomes shallow, and you produce the REMs that so fascinated Aserinsky all those years ago. Now you are dreaming. Everyone experiences this REM stage about five times each night, with each of the periods lasting an average of twenty minutes. Although some people think that they don’t dream, if they are woken up directly after exhibiting REMs, more often than not, they will report a dream. It is not that some individuals don’t dream, but rather that they don’t remember their dreams in the morning.

Additional work has shown that two curious things happen to your body when you dream. First, your genitals become active, with men getting an erection and women exhibiting increased vaginal lubrication. Although hailed as a breakthrough in the 1960s, some researchers have argued that the effect may have been discovered long before, pointing out, for example, that one of the 17,000-year-old cave paintings in Lascaux depicts a dreaming Cro-Magnon hunter with an erect penis (then again, he might just have really enjoyed hunting). Second, although your brain and genitalia are very active during dreaming, the rest of your body is not. In fact, your brainstem completely blocks any movement of your limbs and torso in order to prevent you acting out your dreams and possibly hurting yourself.

Just as your brain can fool you into seeing an afterimage of a ghost, it can also trick you into thinking that you have encountered an evil entity. As you move between ‘Stage 1’ and the REM state your brain sometimes becomes confused, causing you to experience the hypnagogic and hypnopompic imagery associated with ‘Stage 1’, but the sexual arousal and paralysis associated with the REM state. This terrifying combination causes you to feel as if a heavy weight is sitting on your chest and pinning you to the bed, sense (and sometimes see) an evil entity or two, and believe that you are having a rather odd form of intercourse.

For centuries a significant percentage of the public have convinced themselves that they have been attacked by demons, ghosts and aliens. Not only have sleep researchers revealed the true nature of such experiences, but also uncovered the best way of banishing these entities from your bedroom. Perhaps not surprisingly, this does not involve extensive chanting, the sprinkling of holy water or an elaborate exorcism. In fact, it turns out that all you have to do is try your best to wiggle a finger or blink. Even the smallest of movements will help your brain shift from the REM state to ‘Stage 1’ of sleep, and before you know it you will be wide awake and safely back in the land of the living.

Those who believe in ghosts have now been forced to accept that the incubus experience is not evidence of hell, but rather a clever trick of the mind. However, rather than jettison their belief in hauntings, they have focused their attention on an altogether trickier problem - the many ghost sightings that happen when people are far from sleep.


Would you like to see a ghost right now? If so, stare at the small white dot in the left-hand box below for about thirty seconds, and then look at the small black dot in the empty right-hand box. After a few moments you should see a mysterious woman in white emerge in front of your eyes. If you repeat the exercise, but look at a white wall rather than the tiny box, you will see a giant ghost projected onto the wall.


Psychologists refer to the ghostly figure that you just saw (and that many of you will continue to see for the next few minutes - sorry about that) as an 'afterimage'. Your perception of colour is based on three systems. Each of these systems is based around two colours, with one dealing with the red-green continuum, another with blue-yellow and the third with black-white. In each of these systems the two colours oppose one another and can't be seen together. For example, when the eye and brain encounter the colour red, the 'red' half of the red-green system is activated, disabling your ability to see anything green at the same time (this explains why you never see colours that appear yellowish-blue or reddish-green).

When you stared at the solid black image a few moments ago you unwittingly forced the 'black-white' neurons to quieten down for a very long period of time. Then, when you shifted your attention to the empty box, the neurons became activated. However, because they were already in a quiet state, the activation made them become over-excited, creating a rebound effect that resulted in a white afterimage.

The Rose Without a Thorn

Hampton Court Palace has a long and controversial history. In the early 1500s the Archbishop of York, Cardinal Thomas Wolsey, invested seven years of his life and over 200,000 gold crowns building a palace fit for a king. A few years after completing the project Wolsey fell out of favour with the reigning monarch, Henry VIII, and felt it would be politically expedient to gift his beloved palace to the Royal family. Henry graciously accepted Wolsey’s kind offer, expanded the estate to ensure that it could hold his thousand-strong court, and promptly moved in. The palace went on to become home to some of Britain’s most famous kings and queens before being opened to the public in the mid-nineteenth century. Nowadays Hampton Court Palace is one of Britain’s most popular historical attractions, playing host to more than half a million visitors each year.

The palace is famous for many things. It houses invaluable works of art from the Royal Collection, contains the best preserved medieval hall in Britain, and boasts giant Tudor kitchens designed to feed 600 twice a day. Oh, and one other thing. It is also one of the most haunted buildings in Britain. Various spirits allegedly haunt the palace. There is, for example, a ‘lady in grey’ who walks through the cobbled courtyards regular as clockwork, a ‘woman in blue’ who continuously searches for her lost child, and a phantom dog that lives in Wolsey’s closet. However, despite stiff competition, Hampton Court’s most famous spirit is that of Catherine Howard.

Henry VIII did not have a great track record when it came to relationships, of course. He cheated on his first wife, beheaded his second, lost his third while she was giving birth to his only son, and divorced his fourth. In a move that would make even the most experienced marriage counsellor raise an eyebrow, the 49-year-old Henry then became infatuated with a 19-year-old courtier named Catherine Howard. After a brief period of wooing Henry married Howard, publicly declaring that she was his ‘rose without a thorn’.

A few months after getting married, Howard found herself very much in love. Unfortunately, the apple of her eye was not her husband Henry, but rather a young courtier named Thomas Culpepper (who, according to several accounts more than lived up to his reputation as a ‘gentleman of the bedchamber’). News of their affair eventually reached Henry, who promptly decided to fetch the garden shears and remove the head of his beloved rose. Upon hearing the bad news, Catherine was understandably upset, and ran to Henry to plead for her life, but was stopped by Royal guards and dragged back through the corridors of the palace to her apartments. A few months later both Thomas Culpepper and Catherine Howard were beheaded at the Tower of London.

The ghost of Catherine Howard is said to haunt the corridor that she was dragged down against her will. By the turn of the last century this area of the palace had become associated with a whole host of ghostly experiences, including sightings of a ‘woman in white’ and reports of inexplicable screams.

In January 2001 a palace official telephoned me, explained that there had been a recent surge in Howard-related phenomena, and wondered whether I might be interested in investigating.6 Eager to use the opportunity to discover more about hauntings I quickly put together an experiment, assembled a research team, photocopied hundreds of blank questionnaires, loaded up my car and headed off to the palace for a five-day investigation.

The palace had called a press conference to announce the start of my study, and had attracted the attention of journalists from all around the world. We decided to make the press conference a two-part affair, with a palace official talking about the history of the haunting in the first half, a brief break, and then my good self describing the forthcoming investigation. A palace historian kicked off the proceedings by telling a packed room of reporters what happened when Henry met Cathy. During the brief break I stepped outside to get some fresh air and the strangest thing happened. A car containing two tipsy teenagers drove slowly past me. One of the teenagers wound down the window and threw an egg at me. The egg smashed on my shirt. Unable to change, I tried to remove the worst of the stains and then returned to the press conference. A few minutes into my talk one of the journalists noticed the marks on my shirt and, assuming that it was ectoplasm, asked whether Catherine Howard had already slimed me. I replied ‘Yes. This is going to be a tougher investigation than I first thought.’ Although said in jest, my comment was to prove prophetic.

Prior to the experiment, I had asked the palace to supply me with a floor plan of the corridor that would have held such unpleasant memories for Catherine Howard. I then met with Ian Franklin, a palace warder who had carefully catalogued a century of reports of unusual phenomena experienced by staff and visitors, and asked him to secretly place crosses on the floor plan to indicate where people had consistently reported their experiences. To avoid any possible bias during the investigation, neither I, nor any other member of the research team knew which areas had been marked by Ian.

During the day groups of visitors were transformed into ghost hunters. After hearing a brief talk about the project, each participant was handed a blank floor plan, asked to wander along the corridor and place an ‘X’ on the floor plan to indicate the location of any unusual experiences that they might have (essentially playing a game of ‘spot the ghoul’). Each night we would place a variety of sensors and a £60,000 heat imager in the corridor in the hope of catching Catherine mid-‘boo’.

Day one of the investigation went badly, with several participants wandering into the wrong corridor and then wondering why the floor plan was so wildly inaccurate. On day two we were joined by a woman who claimed to be the reincarnation of Catherine Howard, and said that she could provide a unique first person perspective on the proceedings (‘Actually, I was dragged up the corridor, not down it’, ‘Not sure that the new paint job in the kitchens works for me’, etc). On day three a Brazilian film crew attempted to film in the haunted corridor but the presenter suddenly had an anxiety attack and left the palace without completing the piece. Day four turned out to be especially interesting. The team (which now included the reincarnated Catherine Howard) assembled in the morning as usual and reviewed the heat sensor data from the previous night. It was immediately obvious that something very strange had taken place, with the graphs showing a massive spike in temperature around 6 a.m. We eagerly rewound the recording from the thermal imager to discover if we had caught Catherine on tape. Dead on 6 a.m. the doors at one end of the corridor burst open and in walked a figure. The reincarnated Catherine Howard instantly recognized the figure as a member of Henry VIII’s court. However, a few seconds later the proceedings took a decidedly more sceptical turn when we saw the figure walk over to a cupboard, remove a vacuum cleaner and start to clean the carpets. Thankfully, the data from the rest of the investigation proved more revealing.


Field footage of thermal ‘ghost’

First of all, people who believed in ghosts experienced significantly more strange sensations than the sceptics. Interestingly, these odd experiences were not randomly spread throughout the corridor but rather stacked up in certain areas. Even more interestingly, these areas corresponded to the ones that Ian Franklin had identified from analysis of previous reports. Given that neither the team nor volunteers knew the location of these areas during the study, it was strong evidence that something strange was happening.

We have obtained the same pattern of findings in several investigations at other haunted locations. Time and again those who believe in the paranormal experience more ghosts than those who don’t, and these sensations frequently occur in places that have a reputation for being haunted. As I loaded my equipment back into my car and said goodbye to our well-meaning but intensely annoying Catherine Howard wannabe, one question nagged away in my mind. Why?

The Machine in the Ghost

Spend any time looking at websites about ghost-hunting or reading books about hauntings and you will soon come across the ‘Stone Tape Theory’. According to its proponents, ghosts are the result of buildings recording and then replaying past events. To put it another way, ghosts don’t just walk through walls but are actually part of them. The idea has emotional appeal but, from a scientific perspective, suffers from three significant problems. First, the idea is quite literally a work of fiction. In December 1972 the BBC broadcast a Christmas ghost story entitled The Stone Tape. Written by Nigel Kneale (who also penned the fabulous Quatermass), the play centres on a group of scientists investigating an old haunted house. The researchers discover that the stone in one of the rooms is capable of recording past events, and that the alleged ghosts are actually these recordings being replayed. Curious to discover more, the team carry out various experiments and (as is often the way when fictional scientists meddle with the unknown) unwittingly release a malevolent force into the world. The second problem with the theory is that it is completely implausible - as far as we know, there is no way that information about events can be stored in the fabric of a building. And the third and final problem - and from a scientific perspective this is perhaps the biggest stumbling block - is that there is not a shred of evidence to suggest that it is true.

Thankfully, other scientists have come up with more plausible ways of explaining things that go bump in the night. In the 1950s Mr G. W. Lambert, the president of the Society for Psychical Research, suggested that the answer lay not in the walls of haunted buildings but rather in the natural movement of earth and water deep beneath their foundations.8


Psychical researcher Tony Cornell carried out a great deal of fascinating work into the unknown, but perhaps his strangest series of studies aimed to assess the reliability of eyewitness testimony for ghosts.9 The idea was simple. First, Cornell and his colleagues would dress up as apparitions, stand in various public spaces at night, and attract the attention of passers-by. Next, other members of the research team would interview these eyewitnesses and assess the accuracy of their testimony. However, as is often the case with supernatural science, the studies proved surprisingly difficult to conduct.

In their initial experiment Cornell wrapped himself up in a white sheet and spent several nights walking around a dark park in the centre of Cambridge. Although 80 people were in a position to see the fake spirit, none of them appeared to notice the strange goings-on. Wondering if the disappointing results were due to poor illumination Cornell put the sheet on again and spent several nights walking around a well-lit Cambridge graveyard. A total of 90 cars, 40 cyclists and 12 pedestrians passed by, but only four people appeared to notice the apparition. Of these, two were interviewed, with one saying that he had assumed that the 'ghost' was part of an art project and the other remarking that the person under the sheet 'surely must be mad'. In a final attempt to be spotted, Cornell contacted a local cinema and arranged to re-stage his ghost walk in front of the screen just prior to the showing of an X-rated film (chosen 'to safeguard against children being present'). The audience were then asked to raise their hands if they had seen something unusual, revealing that a third of the audience had failed to notice the fake spirit. The testimony from those who did spot the figure was often far from accurate, and included a description of a young girl dressed in a summer frock, a woman dressed in a heavy coat, and a polar bear ambling across the screen.

Cornell's findings suggest that if the dead do indeed walk among us they might benefit from wearing a high-visibility vest.

Gauld and Cornell found a house that was scheduled for demolition and persuaded the local council to give it to them for the purpose of serious scientific research. The duo started off by cementing a powerful vibrating machine to the wall of the house. Next they slung a long rope around the chimney and attached a heavy weight to the end of the rope. They then ventured inside the house and carefully positioned 13 ‘test’ objects in different rooms, for example, placing a marble on the floor in one room and a teacup and saucer on a shelf in another. Preparations complete, they moved onto the second stage of the experiment.

Gauld positioned himself inside the house and Cornell switched on the giant vibrator. The entire house shook but none of the test objects moved an inch. Cornell then arranged for the heavy weight on the end of the rope to be lifted and slammed into the side of the building. All the test objects remained unmoved by the experience. The following day Gauld and Cornell returned to the house, turned the vibrator up to 11, and finally managed to get the teacup to rotate in the saucer. The dynamic duo then repositioned the vibrator for even greater effect and took up positions in the house for one final test. As a colleague turned the vibrator’s dial to maximum Gauld and Cornell felt the entire house shake. Dirt came crashing down the chimney, slabs of plaster fell from the ceiling, and a large crack emerged in one of the bedroom walls. Subsequently describing their time there as ‘quite our most terrifying experience in pursuit of a poltergeist’, they stood their ground and observed that even under these extreme conditions only a few of the test objects moved (a plastic beaker fell over, the cup and saucer fell off the shelf and a plaster of Paris donkey moved a fraction of an inch away from the wall). After putting their lives on the line in the pursuit of scientific knowledge, Gauld and Cornell concluded that Lambert’s theory simply didn’t hold water.

Lambert is not the only one to suggest that hauntings might be the result of bad vibrations. In my previous book, Quirkology, I described another idea put forward by electrical engineer Vic Tandy.10 In 1998, Tandy was working in a laboratory that had a reputation for being haunted. Working alone in the lab late one August night, he started to feel increasingly uncomfortable and had the distinct impression of being watched. As he slowly turned around he saw an indistinct grey figure slowly emerge from the left side of his peripheral vision. With the hair on the back of his neck standing to attention, Tandy eventually built up the courage to look directly at the figure. As he did, it faded away and disappeared.

Tandy was a keen fencer and the following day brought his foil into the laboratory for repairs. As he clamped the foil into a vice, it started to vibrate frantically. Although initially baffled, he eventually figured out that the air conditioning unit in the room was producing a low frequency sound wave that fell well below the human hearing threshold. These waves, referred to as ‘infrasound’, vibrate at a frequency of around 17Hz, and are capable of producing weird effects. Tandy speculated that in some allegedly haunted buildings certain naturally occurring phenomena, such as strong winds blowing across an open window or the rumble of nearby traffic, could be creating infrasound and giving people strange experiences that they incorrectly attribute to the presence of spirits.

There is some evidence to support Tandy’s idea. For example, in 2000 he reported investigating a fourteenth-century cellar in Coventry that had a reputation for being haunted, and found infrasound in the part of the cellar where many people had reported seeing apparitions.11 As I also noted in Quirkology, some additional research has suggested that people do have strange experiences when exposed to low frequency sounds. However, although the theory might explain some alleged ghostly activity, the required combination of strong winds, specifically shaped windows and nearby traffic mean that it is unlikely to account for a large number of hauntings.

Of course, as a scientific explanations for spirits, infra-sound is not the only show in town… .

Waiting for God

Neuropsychologist Michael Persinger, from Laurentian University in Canada, believes that ghostly experiences are caused by the brain malfunctioning and, more controversially, that these sensations can be easily elicited by applying very weak magnetic fields to the outside of the skull.12

In a typical Persinger study participants are led into a laboratory and asked to sit in a comfortable chair. They then have a helmet placed on their heads, are blindfolded, and are asked to relax for about 40 minutes. During this time several solenoids hidden in the helmet generate extremely weak magnetic fields around the participant. Sometimes these fields are focused over the right side of the head, at other times they switch to the left and once in a while they circle around the skull. Finally the helmet and blindfold are removed and the participant is asked to complete a questionnaire indicating if they experienced any strange sensations, such as the sense of a presence, vivid images, odd smells, being sexually aroused or coming face to face with God.

After years of experimentation, Persinger claims that around 80 per cent of participants tick the ‘yes’ box to at least one of these experiences, with some even going for the ‘all of the above’ option. The study has featured in lots of science documentaries, resulting in several presenters and journalists putting Persinger’s magic helmet on their heads in the hope of meeting their maker. For the most part, they have not been disappointed. Parapsychologist Sue Blackmore felt as if something had got hold of her leg and dragged it up the wall, followed by a sudden sense of intense anger (which is exactly how I would feel if someone took my leg and dragged it up a wall). Scientific Americancolumnist and sceptic of the paranormal Michael Shermer had an equally strange time under the influence of the helmet, feeling a strange presence rush past him, followed by a sense that he was drifting out of his body. Persinger does not, however, have a 100 per cent track record, with evolutionary biologist and well-known atheist Richard Dawkins feeling very little, followed by a strong sense of disappointment.

Despite the occasional unresponsive atheist, all was going well with Persinger’s theory until a team of Swedish psychologists, lead by Pehr Granqvist from Uppsala University, decided to carry out the same type of experiments.13It all started well, with some of the Swedes visiting Persinger’s laboratory and even borrowing a portable version of one of his helmets for their own study. However, Granqvist became worried that some of Persinger’s participants may have known what was expected of them and their experiences could therefore have been due to suggestion rather than the subtle magnetic fields. To rule out this possibility in his own work, Granqvist had all of his participants wear Persinger’s borrowed helmet, but ensured that the coils were only turned on for half of the participants. Neither the participants nor the experimenters knew when the magnetic fields were on and when they were off.

The results were remarkable. Granqvist discovered that the magnetic fields had absolutely no effect. Three of his participants reported intense spiritual experiences, but two of these were not being exposed to the magnetic fields at the time. Likewise, 22 people reported more subtle experiences, but 11 of them were in the ‘coils off’ condition. When Granqvist’s work was published in 2004, Persinger argued that the poor showing may have been due, in part, to the participants in the ‘coils on’ condition only being exposed to the magnetic fields for 15 minutes, or Granqvist running the DOS-based software controlling the coils in Windows and thus possibly altering the nature of the magnetic fields. The Swedish team defended their work and stood by their findings.

Worse was to come for Persinger. In 2009, psychologist Chris French and his colleagues from Goldsmiths College in London carried out their own investigation into Persinger’s ideas by hiding coils behind the walls of a featureless white room, and then asking people to wander around the room and report any strange sensations.14 Seventy-nine people visited this most scientific of haunted houses for about 50 minutes each. Following in the footsteps of Granqvist, French and his team ensured that the coils were only switched on for half of the visits, and that neither the participants nor experimenters knew whether the coils were on or off. The magnetic fields had absolutely no effect on whether or not people reported a strange experience.

Some commentators have noted that we are all subjected to far greater magnetic fields whenever we use a hairdryer or turn on a television set, and so, if the theory worked, we would experience ghosts far more frequently.

The idea of infrasonic ghosts and electromagnetic spirits has caught the imagination of the media and public alike. However, the scientific jury is unconvinced.

So has anyone solved the mystery of hauntings? Before we delve deeper, it is time to discover more about the spectre of a rather strange clerical ghost.

The Power of Raman Spectroscopy

A few years ago I conducted an unusual experiment as part of a television series on human behaviour. We assembled 20 unsuspecting volunteers in a room, had them sit in four rows of chairs and explained that we were about to test their sense of smell. They were shown a small perfume bottle containing bright green liquid and we explained that once the lid of the bottle was unscrewed a strong peppermint smell would permeate throughout the room. We then carefully removed the lid and asked people to raise their hands once they could smell the peppermint. Within moments a few people in the front row raised their hands. Seconds later those in the second row followed suit. Before long about half of the group had their hands in the air. When we asked people to describe the smell they said that it was fresh, pleasant and stimulating. There was just one small problem. As you might have guessed by now, the bottle actually contained a mixture of water and odourless dye. The peppermint smell existed solely in the minds of the participants and was designed to demonstrate the power of suggestion.

This demonstration, first conducted by Edwin Emery Slosson in 1899 (who, according to a report from the time, was ‘obliged to stop the experiment, for some of the front row seats were being unpleasantly affected and were about to leave the room’), has been carried out in psychology departments across the land for over a hundred years.15

In the late 1970s sensory scientist Michael O’Mahony from the University of California took the idea to new heights when he persuaded the BBC to undertake an ingenious version of the study during a live programme.16O’Mahony constructed some mock scientific apparatus (think weird-looking large cone, masses of wires and several oscilloscopes), and managed to keep a straight face as he told viewers that this newly devised ‘taste trap’ used ‘Raman Spectroscopy’ to transmit smells via sound. He then proudly announced that the stimulus would be a country smell. Unfortunately, the studio audience interpreted his comments to mean ‘manure’, resulting in a significant amount of smutty laughter. After clarifying that they would not be broadcasting the smell of shit into people’s homes, the research team played a standard Dolby tuning tone for ten seconds. Just as the bottles in the more pedestrian versions of the study contained nothing but water, so the tone did not actually have the ability to induce smells.

Viewers were then asked to contact the television station and describe their experiences. A few hundred viewers responded, with the majority stating that they had detected a strong smell of ‘hay’, ‘grass’ and ‘flowers’. Although they were explicitly told that the smell would not be manure-related, several people mentioned that they had detected the subtle hint of silage. Many respondents described how the tone had brought about more dramatic symptoms, including hay fever attacks, sudden bouts of sneezing and dizziness.

These experiments demonstrate how nothing more than the power of expectation can cause some people to experience various smells. James Houran (of internet dating and ghost-busting fame) also believes that they play a vital role in unlocking the mystery of hauntings.

Houran speculated that if suggestible people believe that they are in a haunted house, they may experience the strange sensations typically attributed to ghostly activity. In addition, he noted that those experiences are likely to create a feeling of fear that will cause people to become hyper-vigilant and pay attention to the subtlest of signals.17 They will suddenly notice that tiny creak in the floorboards, the swaying of the curtains, or a brief whiff of burning. All of this will cause them to become even more afraid and therefore exhibit even greater hyper-vigilance. The process feeds on itself until the person starts to become highly agitated, anxious and prone to more extreme sensations and hallucinations.

The findings from many studies support Houran’s ideas. In my own work, those who believed in ghosts reported far more weird experiences than sceptics, and their sensations tended to focus around the type of scary-looking locations that frequently feature in horror films. In the experiments investigating the (lack of) impact of weak magnetic fields on the brain, those reporting strange experiences tended to be far more suggestible than most. Although these findings are encouraging, the ultimate testing of the theory involves taking suggestible people to a place that does not have a reputation for being haunted, making them believe that it does, and seeing if they experience the same kind of ghostly activity reported in ‘genuine’ hauntings. Houran has conducted several of these experiments, with intriguing results.

In one experiment he took over a disused theatre that had absolutely no reputation for being haunted, and asked two groups of people to walk around it and report how they felt.18 Houran told one group that the theatre was associated with lots of ghostly activity and the other that the building was simply undergoing renovation. Those in the ‘this building is haunted’ group reported weird sensations all over the place, while the other group experienced nothing unusual. In another study Houran asked a married couple living in a house that had no reputation for ghostly activity to spend a month making a note of any ‘unusual occurrences’ that they noticed in their home.19 Reporting the results in the paper ‘Diary of events in a thoroughly unhaunted house’, he noted that the couple reported an amazing 22 weird events, including the inexplicable malfunctioning of their telephone, their name being muttered by a ghostly presence, and the strange movement of a souvenir voodoo mask along a shelf.

Although these studies are impressive, perhaps the prize for the best test of Houran’s theory goes to journalist Frank Smyth.

The Phantom Vicar of Ratcliffe Wharf

In 1970 Frank Smyth was an associate editor of a magazine dealing with paranormal phenomena known as Man, Myth and Magic.20 One Sunday morning Smyth travelled to Ratcliffe Wharf in London’s Docklands to meet his friend John Philby (son of spy Kim Philby). Throughout the nineteenth century Ratcliffe Wharf was a busy dock. As a result of the constant coming and going of sailors, it also became a hotbed of iniquity, crammed full of gambling dens, drinking houses and brothels. Philby was renovating an old warehouse in the area, and suggested to Smyth that it might be fun to create a ghost story.

After a couple of hours of productive brainstorming in a nearby pub, Smyth and Philby emerged with the phantom vicar of Ratcliffe Wharf - an emotive tale of sex, sailors, and murder. So, if you are sitting comfortably, I will begin …

In the early 1800s a former vicar of the Wharf’s largest church, St Anne’s, set up a guesthouse in the area for sailors. However, when business failed to boom this most corrupt of clergymen adopted more unsavoury ways of making ends meet. The vicar would pay young attractive women to tempt sailors back into his guest house, ply the men with drink, and then invite them upstairs for a bit of ‘how’s your father?’ When the men stripped off and climbed into bed, the vicar would emerge from his hiding place in the room, batter them to death with his silver-topped cane, steal their money and dump their lifeless bodies into the muddy Thames. According to local lore, the vicar’s spectre still haunts the area.

After carefully checking that the area was not associated with any ghostly activity, Frank described his completely fictitious story in the latest issue of Man, Myth and Magic, noting that both he and Philby had actually seen the ghost.

Three years later a BBC documentary programme described the hoax, presenting a dramatized account of the phantom vicar of Ratcliffe Wharf (including a sign outside the guesthouse where the vicar used pretty women to lure sailors, appropriately announcing ‘Lodgings for Seamen’) and went in search of people who had seen the non-existent ghost. They didn’t have to look far. One local woman reported seeing the ghostly vicar and described how he was dressed in a white shirt, with a cloak and flowing grey hair. Believing the ecclesiastical spirit to be a rather lecherous figure, the woman described how she often had the sense that he was watching her when she undressed at night. Next, a landlord in the area described how his daughter and her two-year-old son had had a chilling encounter with the spectre when they had come to stay with him. After several sleepless nights the child pointed to an area of the room and screamed out that he didn’t like the man standing there. The child’s mother then turned around and saw the ghostly vicar looking at her. Other witnesses included a workman who had seen the vicar walk round a corner before melting away in front of his eyes, and two policemen who told the untruth, the whole untruth and nothing but the untruth about the ghostly activity in the wharf.

The phantom vicar of Ratcliffe Wharf is a vivid vindication of Houran’s theory. Hauntings do not require genuine ghosts, recording walls, underground streams, low frequency sound waves or weak magnetic fields. Instead, all it takes is the power of suggestion.

The Big Question

Although the psychology of suggestion accounts for many ghostly phenomena, there still exists one final mystery - why on earth should our sophisticated brains have evolved to detect non-existent ghostly entities?

Scientists have proposed various theories to account for what goes bump in our minds. Psychologist Jesse Bering from the University of Arkansas has suggested that both ghosts and God help forge a more honest society by convincing people that they are constantly being watched.21 Bering and his team tested their idea by carrying out a somewhat strange experiment. In their study, students were asked to complete an intelligence test. The test had been carefully constructed to ensure that the students could cheat if they wanted to, and that the experimenters could secretly monitor each person’s level of deception. Just before taking the test, a randomly selected group of the students was told that the test room was apparently haunted. As predicted by the ‘ghosts make people more honest’ theory, the students who thought that they were in a haunted room were far less likely to cheat on the test.

However, perhaps the most popular theory to account for the evolution of ghostly experiences concerns the ‘Hypersensitive Agency Detection Device’.22 Oxford University psychologist Justin Barrett believes that the idea of ‘agency’ - being able to figure out why people act the way they do - is essential to our everyday interactions with one another. In fact, it is so important that Barrett thinks the part of the brain responsible for detecting such agency often goes into overdrive, causing people to see human-like behaviour in even the most meaningless stimuli. In the 1940s psychologists Fritz Heider and Mary-Ann Simmel conducted a now classic experiment that provides a beautiful illustration of Barrett’s point. Heider and Simmel created a short cartoon animation in which a large triangle, small triangle and a circle moved in and out of a box. They then showed the meaningless cartoon to people and asked them to describe what was happening. Most people instantly created elaborate stories to explain the cartoon, saying, for example, that perhaps the circle was in love with the little triangle, and the big triangle was attempting to steal away the circle, but that the little triangle fought back, and the small triangle and circle eventually lived happily ever after.

In short, people saw agency where none existed. Barrett believes that the same concept helps explain God, ghosts and goblins. According to the theory, many people are very reluctant to think that certain events are meaningless, and are all too eager to assume that they are the work of invisible entities. They might, for instance, experience an amazing stroke of good luck and assume it is angels at work, be struck down with an illness and see it as evidence of demons, or hear a creaking door and attribute it to a ghostly woman in white. If Barrett is right, ghosts are not the result of superstitious thinking. Neither are they spirits returning from the dead. Instead, they are simply the price we pay for having remarkable brains that can effortlessly figure out why other people behave the way they do. As such, ghosts are an essential part of our everyday lives.