The Unpersuadables: Adventures with the Enemies of Science (13 page)

As you might expect, it takes time for the brain to take its multisensory barrage of pulses and to process it into its grand illusion.
Estimates vary
, but the most dramatic that I came across had it that we are all living half a second in the past. The ‘now’ we appear to be experiencing is another illusion: a prediction that the brain calculates once it has received the already slightly out-of-date information from the senses. If a ball is thrown into the air, your brain predicts it will be slightly closer by the time you ‘see’ it and therefore ‘moves’ it to the correct place, enabling you to catch it.

Vision is of such importance to the construction of your virtual realm that
one-third of the human brain is devoted to its processing
. And yet your eyes themselves are nowhere near as good as you have been led to assume. Hold out your arm and look at your thumbnail. That is about the extent to which your sight is clear, coloured and detailed.
Beyond ten degrees from this vivid centre
, your vision is blurred, black and white and only able to detect potentially important information. It achieves the effect of showing you a detailed whole by building it up surreptitiously. Your eye darts at high speed around the scene that you are in and takes multiple high-definition snapshots of it. You are fooled into thinking your gaze is steady, still and under your conscious control but, in fact, these ‘saccades’ – which are the fastest movements made by the human body –
happen up to five times per second
. They are sensitive to change, patterns, contexts and textures – anything that might trigger a need for the brain to update its best-guess impression of the world. From what it shows you, it edits out the jarring motion of these saccades, as well as the blinks that happen every five seconds (it has been calculated that blinking makes us blind for a total of four hours per day). It also overlays a series of magnificent special effects, including colour and movement and filling in your blind spot and adding depth, generating a 3D version of what, writes
neuroscientist David Eagleman in his book
Incognito
, is only ‘2.5D at best.’

The world appears to be coloured because,
in the back of each eye
, in an area of just one square millimetre, we have three varieties of cone that interpret incoming visual information as either red, blue or green. Every colour you will ever see is a blend of this triumvirate of basics. We assume that this is simply what the world looks like but, yet again, this is a lie. The atoms that make everything up have no colour. There are no colours inside the brain. Light waves are not coloured. So where are colours? They are another illusion, created in specific cells in the brain that have been located, so I am informed,
in the visual area of the striate cortex V
₄
. A fish such as a skate has no colour cones at all and so experiences the world in black and white. If you now feel superior to the skate and assume that you, the special human, have access to the full and fantastic panoply of shades that make up true reality, then I am afraid that I have to tell you that
some birds and insects have four, five or even six colour receptors
, compared to our sorry three. Their experience of the multi-multi-multi-coloured world is impossible for any human to even begin to imagine.

Because sight is of such pre-eminent importance to us, we assume that vision is the best way of negotiating the world. But this, too, is not objectively true. Dogs live, principally, in a world of smells; moles in a world of touch, bats in a world of noise and knifefish in a world of electricity. Their experiences of reality are specialised for their particular environments and survival needs, their perceptions profoundly different and no less valid than ours.

According to Professor Eagleman, ‘Our brain is
aware of very little of what is out there.’ Its preoccupation is with presenting to us – and drawing our attention to – the things that might be important for our well-being. Our ears are only capable of hearing a small number of the sounds that are actually present in our environment; our eyes are blind to whole rainbows of visible light –
less than a ten-trillionth of the spectrum is available to us
. Right now, mobile-phone signals, soap operas, radio-broadcasted music and who knows what else are everywhere: in front of you, above your head,
inside
you. And yet you don’t see them or hear them, because – much like a black-and-white television is blind to blue skies and green seas – you lack the equipment. In a sense, brains operate on a ‘need to know’ basis only. In
Making
up the Mind
, Professor Frith describes the inexact and humble panorama that we inhabit as having a specific use:
it is, he says, a ‘map of signs about future possibilities
.’

The world that you experience as objectively real is your own personal model of reality, and your brain tends to assume that everything new that you experience coheres to that model. There are good reasons for this. It hardly needs to be pointed out that if the brain really is receiving millions of pieces of information (Professor Timothy D. Wilson of the University of Virginia
quotes a figure of over eleven million
, whilst in his book
Straw Dogs
,
Professor John Gray has it at ‘perhaps 14 million
bits of information per second’), we are consciously aware of nowhere near that amount.
As V. S. Ramachandran writes, ‘The brain must have some way
of sifting through this superabundance of detail.’

What are you aware of as you read this? The feeling of your back on the chair, an early rumble of hunger from your belly, the sound of nearby traffic, the fact that you need to get off the train at the next stop? It is not nearly eleven million things. Indeed, it is thought that
the maximum number of points of information we are able to appreciate consciously
at any one time is less than forty. One part of this sifting process involves the matching of incoming information with the personal belief system that you have about the world. Any information that fits is incorporated effortlessly into your experience of now. But what of the information that runs counter to your belief system? What then?
‘One option is to revise your story
and create a new model about the world and about yourself,’ writes Ramachandran. ‘The problem is that if you did this for every little piece of threatening information, your behaviour would soon become chaotic and unstable. You would go mad.’ So instead we minimise, distort, rationalise and even hallucinate our way into disregarding this information. And the cost we pay for our feeling of sensible, sane and simple coherence? We lie to ourselves.

It is possible to catch the liar out. The brain may excel at making accurate predictions about what should be out there, but it sometimes gets it wrong. People who lose portions of their sight have been known to see
cartoon characters, loved ones and historical characters
romping
across their blind spots, as their brains frantically try to guess at what should be in the darkened gaps.
Ten per cent of elderly people
who suffer from severe blindness or deafness experience hallucinations due to similar processes. Some stroke patients live, at least temporarily, in a state of complete psychological denial of their paralysis. A
Dr Clarence W. Olsen has spoken
of a patient who lost sensation and movement in her left side. Because her numb limbs now felt and behaved as if they belonged to someone else, her mind explained them in exactly this way – by telling her they actually belonged to someone else. Olsen has recounted, ‘When she was shown that the limbs were attached to her, she said, “But my eyes and my feelings don’t agree, and I must believe my feelings.”’ In his book
Altered Egos
, Dr Todd E. Feinberg writes of this and similar patients, including a forty-eight-year-old woman who, when asked about her numb side, grumbled, ‘That’s an old man. He stays in bed all the time.’

It is important to underline that none of these people are ‘mad’. Their brains have simply failed to adjust to their catastrophic new realities. In most cases of this sort of denial,
it takes between two and three weeks for their unpleasant situation
to be absorbed into their working perception. Experiments on healthy individuals have revealed similar mistakes.
Academics at the University of Wisconsin
made an audio recording of a predictable sentence – ‘The bill was passed by both houses of the legislature’ – but covered a portion of it with static. Almost everyone who heard it said, ‘Yes, I heard the words and the white noise.’ But when asked where the static had actually taken place, a large proportion had no idea at all. Despite the fact that they weren’t all present, they had
heard all the words
. Their brain had predicted what they would be, and produced them. It had lied. We tend to see and hear what we expect to see and hear, not necessarily what is there.

Other incredible insights come from people who have had body parts amputated and, because their brains have not correctly acknowledged the loss, continue to experience their presence as ‘phantom limbs’. In his work,
V. S. Ramachandran has come across
tennis players ‘catching’ balls with phantom arms, women experiencing phantom breasts following a full mastectomy, phantom pain in a phantom appendix and even phantom erections in phantom penises.

The human realm, though, is not simply one of things that we see, sounds that we hear and vanished appendixes that feel sore. The University of Virginia’s Professor Jonathan Haidt writes in
The Happiness Hypothesis
that
our world is ‘not really
one made of rocks, trees and physical objects; it is a world of insults, opportunities, status symbols, betrayals, saints and sinners.’ It is one of beliefs.

One result of this simple fact is that vast differences exist in the behaviours of human brains around the world. Some cultures, for example, experience emotions that are unique.
In New Guinea, the Gururumba men
have a mental state that is known as ‘being a wild pig’ in which they run around stealing things and attacking passersby. Dylan Evans of the University of Bath writes that this emotion ‘is seen as an unwelcome but involuntary event, so people suffering from it are given special consideration which includes relief from financial obligations.’ He adds, ‘The fact that different cultures can produce human beings with different emotional repertoires is testimony to the remarkable plasticity of the human mind … if your culture teaches you that there is an emotion called “being a wild pig” then the chances are you will experience this emotion.’

Many South Koreans are terrified of ‘fan death’
, which they believe is a serious risk if you sleep in the same room as an electric fan. Panicked news reports about fan death are common during the summer and fans are sold with timer switches that automatically shut off after a preset time. In Iceland – a country that boasts a 100 per cent literacy rate –
contractors carrying out huge public works
, such as road building, have to consult with specialists to ensure that they bypass the homes of fairies and gnomes, while builders hire ‘elf-spotters’ to scope the land before work begins on a new house. In China people suffer from a condition known as ‘koro’ in which they feel their sexual organs – penises in men and vulvas and nipples in women – retracting into their bodies.
They have a family member hold their shrinking part in place
, all day and all night, for as long as it takes until the koro threat passes.

Even the nature of a state such as drunkenness is defined by where you come from. In the UK, Australia and the US
we believe that alcohol is a disinhibitor
, so we become flirtatious and aggressive and
inadvisably honest when drunk – even when all we have had is a placebo cocktail. In Latin and Mediterranean countries, meanwhile, it is believed to encourage peacefulness and friendliness – and, for those civilised people, this is precisely what it does. ‘The effects of alcohol on behaviour are determined by cultural rules and norms, not by the chemical effect of ethanol,’ writes the anthropologist Kate Fox in her book
Watching the English
. ‘The basic fact has been proved time and time again. When people think they are drinking alcohol, they behave according to their cultural beliefs about the behavioural effects of alcohol.’

It should not come as a surprise to learn that a good deal of our often faulty beliefs and tendencies come as a result of us being highly tribal. We remain, today, modern creatures with prehistoric thinking equipment. Which perhaps offers a clue as to why it was that – as Louise Ogborn discovered when she was compelled to strip in that McDonald’s back office – we still have an instinct for obedience to authority.
Studies by researchers in Switzerland
have found that we are also programmed to punish, and to take pleasure in revenge.
We have an additional, irresistible urge to divide the world
into ‘us’ and ‘them’.
A study by three major US universities found
that between 90 and 95 per cent of people have an unconscious racial prejudice. Others have observed that
the only thing necessary to trigger tribal behaviour in humans
is the creation of two completely arbitrary groups. Leave them alone in a room and watch it all begin: the people we identify with automatically become a part of our ‘in’ group. A series of unconscious biases flares up around then – haloes surround ‘our’ people, which magnify their virtues and minimise their faults. A dark, opposing magic happens to our view of those who are on the ‘out’. But as damaging as it can be, we need prejudice. It is the shape of our models, the starting point for our guesses about the world.

When our brains are told things that contradict their models, we often enter a state known as ‘cognitive dissonance’. In their book
Mistakes Were Made (But Not By Me)
social psychologists Carol Tavris and Elliot Aronson describe
this as ‘a state of tension that occurs whenever a person holds two cognitions (ideas, attitudes, beliefs, opinions) that are inconsistent, such as “smoking is a dumb thing to do because it
could kill me” and “I smoke two packs a day”. Dissonance produces mental discomfort, ranging from minor pangs to deep anguish; people don’t rest easy until they find a way to reduce it.’ As a result of dissonance, they say, ‘most people, when directly confronted with proof that they are wrong, do not change their point of view or course of action but justify it even more tenaciously.’