The Unpersuadables: Adventures with the Enemies of Science (29 page)

Along this journey, I have given descriptions of our limited perception, cognitive biases and faulty, bickering models. Because the focus has been on our flaws, it might be easy to conclude that the brain is not particularly good at its job. This is not so. The models it creates and the predictions it makes
have
to be largely effective, otherwise we would simply not be able to operate. Indeed, there is a good chance that you have no idea how clever you really are. This is because you have no direct access to your unconscious models – the bits of yourself that are the most brilliant, mathematically, analytically and creatively. In fact, the part of your mind that you do your conscious thinking with is, in the words of Professor David
Eagleman, ‘not at the centre of the action
in the brain, it is far out on a distant edge, hearing but whispers of the activity’. These whispers very often tell of wisdom and calculation whose sophistication might astound you.

Scientists at the Monell Centre
, Philadelphia, had participants in a study smell gauze pads that had been worn under the armpits of people who had watched various films.
Without knowing why
, many of the sniffers could detect which pads had been worn during comedies and which during horrors. Then there are the amazing chick-sexers.
When chickens are born in industrial hatcheries
, they have to be separated by gender. Because newborn chicks look identical, professional sexers are hired to do the work. Unfortunately, the professionals cannot tell you what the difference between a day-old male and a female chick is either. In order to learn, an apprentice sexer just starts working, examining each young bird and
guessing
, while an old master tells them when they are right or not. Somehow, a part of their brain eventually just
gets
it.
Researcher Richard Horsey says
, ‘They just look at the rear end of a chick, and “see” that it is either male or female.’
He quotes one former sexer who says, ‘To be close to 100 per cent and accurate at 800 to 1200 chickens per hour, intuition comes into play in many of your decisions, even if you are not consciously aware of it. As one of my former colleagues said to me … “There was nothing there but I knew it was a cockerel.” This was intuition at work.’ By trial and error – cause and effect – these sexers develop brilliant models for male chick and female chick. Their unconscious minds use the sight of a chick’s backside to compare it with their models, then use emotion to ‘tell’ the sexers the answer.

In an experiment that looked at just how intricately advanced ‘intuition’ can be,
a team led by Professor Antoine Bechara
gave participants $2,000 in play money and four decks of cards and told them they were to use them in a game. Different individual cards won or lost different sums of money. They should just go ahead and turn the cards and try to win as much money as they could. But the cards were not random. In fact, some of the piles were far more profitable than others. On average, it took the gamblers around fifty card-turns before they began to report a conscious ‘hunch’ that some of the decks were more profitable. But when their behaviour was analysed, Professor Bechara discovered something remarkable. Measurements of the electrical conductance of their skin, which can reveal levels of anxiety and nervousness, indicated that their emotions were subtly warning them against the bad decks after
just ten turns
. Their unconscious mind had worked out what was happening far quicker than their conscious minds and had warned them with a hit of
bad feeling
. They knew before they knew.

All of this seems to border on magic. But the brain, as we know, is also an organ of bias and prejudice whose rapid responses are made possible by its models – stubborn approximations of how the world works. Studies have established that qualified yet overweight job applicants are often assumed to be less intelligent, lazier and more immoral than their thinner counterparts. One sad experiment demonstrated that interviewers can unconsciously attach negative qualities to an applicant after they have seen them
sitting next to
an overweight person in the waiting room.

These unpleasant decisions are compounded by the fact that we
usually don’t even know we have made them. If we did, we might be able to use our rational minds to suppress them. But those instances are rare. Most thinking is emotional, and happens without you even being aware of it. We can’t question ourselves, either. The great electrical thinking-galaxies that bloom and churn behind the eyes of the mind cannot tell us why they have decided that sitting beside an overweight person is bad. They cannot speak.

All of which leads us to an intriguing and essential problem. If our unconscious is mute, and yet driving most of our decisions, then how can we explain our own behaviour? As Professor Leon Festinger and his co-researchers into confirmation bias found: when confronted by a new fact, we feel an instantaneous, emotional hunch that pulls us in the direction of an opinion. We then look for evidence that supports our hunch until we hit the ‘makes sense stopping rule’ and our thinking ceases. Our mind completes the process by fooling us into believing that we have made an objective survey of the arguments, then gives us a pleasurable neurochemical hit of
feeling
as a reward. But all we have really done is confirm the hunch, silence the dissonance, reinforce the model.

If this is so, and all we are doing is defending the conclusion that our mute unconscious has already come to, it suggests something terrifying: that we don’t know why we believe what we believe; we don’t know why we do what we do. It says that all we are really up to when justifying our actions and beliefs is guessing. All we
really
know is how we feel, and our explanations for how we feel are inventions. They
must
be – because we cannot talk to the parts of our minds that have made these decisions. A homophobe cannot ask his own unconscious why he believes that homosexuality is evil. All he knows is that, when he thinks about gay people, his emotions say ‘withdraw.’ He feels disgust. Then he weaves a narrative that explains his disgust. He tells a story.

As we grow – and our knowledge of causes and effects become ever more sophisticated – so too do our natural abilities as storytellers. As
Professor Timothy Wilson writes in
Redirect
, ‘One of the main differences between us and the rest of the animal kingdom is that we have a large brain with which we can construct elaborate theories and explanations
about what is happening in the world and why.’

At its most basic level, a story is a description of something happening that contains some form of sensation, or drama. It is, in other words, an explanation of cause and effect that is soaked in emotion. Human thinking must take this form because we are biologically incapable of removing the
feeling
from it. That is how our thoughts are delivered.

And complex brains create complex stories. In
Six Impossible Things Before Breakfast
, Professor Lewis Wolpert writes that, aside from
their understanding that germs and food can cause sickness
, ‘there is a quite widespread belief among children that illness is a punishment for wrongdoing.’ From an early age, a simple observation of a person falling sick is liable to become a narrative of good and evil and vengeance for sin. We are natural-born storytellers who have a propensity to believe our own tales.

A series of remarkable scientific discoveries, going back to the nineteenth century, have bolstered this view. They have assigned it a word, which describes what we do when we unknowingly invent explanations for behaviours and beliefs whose causes we are actually ignorant of: confabulation.

In 1889 the German psychiatrist Albert Moll
recounted telling a hypnotised woman, ‘After you wake you will take a book from the table and put in on the bookshelf.’ When she came too, she had no conscious memory of having been given this instruction. And yet she dutifully picked up a book and slid it into a space on the shelf. When Moll asked her why she had done this, she said, ‘I do not like to see things so untidy. The shelf is the place for the book, and that is why I put it here.’ She had confabulated a reason for her behaviour, which was actually caused by Moll’s instruction. She thought that she knew why she was putting the book away, but the reason she gave was just a story that her brain had told her, and that she had believed.

Seventy-three years later, researchers at Columbia University
injected epinephrine into some study participants which, unbeknown to them, would make their heart race, their face flush and their hands tremble. Some of the participants were then placed in the company of an angry person, others in the company of someone happy. The subjects with
the angry person reported feeling angry, confabulating a fake reason for their heightened physical sensations. The happy ones did likewise. A control group, who
had been
informed about the effects of epinephrine, correctly put their bodily responses down to the drug. The other participants, though, experienced identical physiological effects and yet confabulated themselves into completely opposing moods. Writes the celebrated neuroscientist Professor Michael Gazzaniga, ‘If there is an obvious explanation, we accept it. When there is not an obvious explanation, we generate one.’

The most startling revelation of confabulation, though, has come from the study of people who suffer from such severe epilepsy that, in order to prevent them having potentially catastrophic global attacks, they have the two hemispheres of their brain surgically separated. These ‘split-brain’ patients have been the subject of a series of profoundly remarkable experiments by Professor Gazzaniga. They revealed the disorienting extent to which we all confabulate, all of the time.

It is a peculiarity of our neural architecture that each half of the brain receives information from, and controls the actions of, the opposite side of the body. The left is master of the right, the right is master of the left.
Why this is remains a mystery
(although some speculate
that it is a mechanism for helping us move the appropriate limb towards sources of light). The hemispheres are not identical. In the majority of people,
the left side is specialised for language
and verbal communication, while
the right is effectively mute
. By itself, the right hemisphere can take information from your senses, but it lacks some essential word- and speech-generating circuitry. This means that it cannot, by itself, ‘talk’. In normal brains, this doesn’t matter as the two hemispheres are connected and information can travel freely between them. But the right hemisphere of a split-brain patient cannot speak. It is, in effect, silenced.

Because this is a slightly complex idea to explain, I’m going to use some colloquial language that some science-literate readers might object to, because of its imprecision. For those people, I should acknowledge that, very strictly speaking, regions of the brain don’t ‘talk’, only people do. Furthermore, no implication should be drawn from what follows
that the left hemisphere equates to consciousness whilst the right does not. Anyhow, for everyone else …

In order to study confabulation, Gazzaniga developed a method of communicating with only the ‘silent’ right hemisphere of a split-brain patient. He began by showing it a picture of a hat. When the professor asked the patient what he had seen, he said that he didn’t know. Because the right hemisphere lacks this critical language and speech circuitry, it could not ‘tell’ the patient that it had seen the hat, so he didn’t know that he had. But when Professor Gazzaniga asked the patient to point with his left hand (which is controlled by the ‘speechless’ right hemisphere) at what he had been shown, it correctly fell upon the hat. The patient knew, but he did not know.

You might be pausing, now, unsure whether you have understood that correctly. This person felt no awareness of having seeing the hat – he had no apparent memory of it whatsoever – and yet, when he was asked what he had seen, he pointed straight at it? That is correct. It really is that strange.

It gets weirder. In his most famous test, Professor Gazzaniga
flashed a picture of a chicken claw
to a man’s left hemisphere and a car covered in snow to his right. He then asked him to point to images that represented what he had seen. One hand went to a chicken, the other to a shovel. Remembering that the patient didn’t realise that he had seen the car covered in snow, and therefore no clue as to
why
he was pointing at the shovel, Professor Gazzaniga asked him to explain his choices. ‘Oh, that’s simple,’ he said. ‘The chicken claw goes with the chicken and you need a shovel to clean out the chicken shed.’

He instantly told a story that explained his inexplicable behaviour – a story
that he believed
. It was a confabulation that would go down in neuro-scientific history.

It did not end there. In further brilliant examples of confabulation,
Gazzaniga flashed the command ‘Walk’
to a patient’s right hemisphere. When he did just that, and the researchers asked him why he had got up, he replied, ‘I’m going to the house to get a Coke.’ Using the same methods, the professor triggered various moods in patients. When he told the right hemisphere of split-brain patient ‘JW’ to laugh, she laughed. When Gazzaniga asked her why she was laughing, she
said, ‘You guys come up and test us every month. What a way to make a living.’

These split-brain patients were special only because the communication between their two hemispheres had been severed. The instant confabulations that they were making – I’m walking because I’m thirsty, I’m laughing because you’re idiots – were not caused by this surgery. The surgery simply enabled Gazzaniga to catch these brains in the act. We
all
confabulate in this way. First we behave. Then we explain. What Gazzaniga’s experiments revealed was the profoundly disturbing fact that our own explanations for our own actions and beliefs can have no basis in truth – and yet we believe them utterly. We are storytellers. That is what we do.