The Hour Between Dog and Wolf: Risk-taking, Gut Feelings and the Biology of Boom and Bust. John Coates
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milliseconds. Coincidentally, that is roughly the time required for a fielder at silly point to catch a ball coming off a bat. It is entirely possible that close fielders rely on the startle response to achieve the almost inhuman response times they display. If so, then, conveniently, perhaps the fielder can catch or avoid a ball in the little time allowed him only if it is coming straight for his head.
Besides the startle response, how can we react fast enough to meet the challenges sports, and daily life, throw at us? As we saw in the previous chapter, humans have adopted a wide range of movements, like those found in sports and dance and modern warfare and even trading, for which evolution has not prepared us. How can these learned movements become so habitual that they approach the speeds needed for sporting success or survival in the wild? To answer this question we should recognise a basic principle at work in our reflexes and automatic behaviours: the higher we rise in the nervous system, moving from the spine to the brain stem to the cortex (where voluntary movement is processed), the more neurons are involved, the longer the distances covered by nervous signals, and the slower the response. To speed our reactions the brain tends therefore to pass control of the movement, once it has been learned, back to lower regions of the brain where programmes for unthinking, automatic and habitual actions are stored. Many of these learned and now-automatic behaviours can be activated in as little as 120 milliseconds.
A glimpse into this process has been provided by a brain-scanning study of people learning the computer game Tetris. At the beginning of the study, large swathes of the trainees’ brains lit up, showing a complex process of learning and voluntary movement; but once they had mastered the game their movements became habitual, and brain activity in the cortex died down. Their brains now drew much less glucose and oxygen, and their speed of reactions increased markedly. Once the players had the knack, they no longer thought about playing the game. This study, and others like it, supports the old saying that when learning begins we are unconscious of our incompetence, and proceed to a stage where we are conscious of our incompetence; then when training begins we move to conscious competence; and as we master our new skill we arrive at the end point of our training – unconscious competence. Thinking, one could say, is something we do only when we are no good at an activity.
One last point. As fast as these automatic reactions may be, they still do not seem quite fast enough for many of the high-speed challenges we face, and may therefore leave us slightly behind the ball, so to speak. The trouble with these reaction times is just that – they are reactions. But good athletes are not in the habit of waiting around for a ball or a fist to appear, or opponents to make their move. Good athletes anticipate. A baseball batter will study a pitcher and narrow down the likely range of his pitches; a cricket close fielder will have registered a hundred tiny details of a batsman’s stance and glance and grip even before the ball has left the bowler’s hand; and a boxer, while dancing and parrying jabs, will pre-consciously scan his opponent’s footwork and head movements, and look for the telltale setting of his stabiliser muscles as he plants himself for a knockout blow. Such information allows the receiving athlete to bring online well-rehearsed motor programmes and to prepare large muscle groups so that there is little to do while the ball or fist is in the air but make subtle adjustments based on its flightpath. Skilled anticipation is crucial to lowering reaction times throughout our physiology.
Let us finish by listening to Ken Dryden, a legendary goalie in ice hockey and one of the most articulate athletes ever, on the importance of anticipation and automatic behaviour: ‘When a game gets close to me, or threatens to get close, my conscious mind goes blank. I feel nothing. I hear nothing, my eyes watch the puck, my body moves – like a goalie moves, like I move; I don’t tell it to move or how to move or where, I don’t know it’s moving, I don’t feel it move – yet it moves. And when my eyes watch the puck, I see things I don’t know I’m seeing … I see something in the way a shooter holds his stick, in the way his body angles and turns, in the way he’s being checked, in what he’s done before that tells me what he’ll do – and my body moves. I let it move. I trust it and the unconscious mind that moves it.’
To sum up, we humans have been equipped over our long evolutionary training period with a large bag of tricks designed to increase our speed of reactions. In the foregoing discussion I have rummaged in this bag and pulled out only a few of our amazing gadgets. But demonstrating how they work should be enough, I hope, to show just how reliant we are on these quick responses for survival in the wild and in war, for success in sports, and for buying back a large block of bonds sold to DuPont.
WHAT LIES BENEATH
In fact, so fast are our reactions that consciousness is frequently left out of the loop. Given that sobering fact, we have to ask: what role does consciousness play in our lives? We experience our consciousness as something residing in our heads, peering out through our eyes much as a driver peers through a windscreen, so we tend to believe that our brain interacts with our body just as a person interacts with a car, choosing the direction and speed and issuing commands to a passive and mechanical device. But this belief does not stand up to scientific scrutiny. As George Loewenstein, an economist at Yale, points out, ‘There is little evidence beyond fallible introspection supporting the standard assumption of complete volitional control of behavior.’ And he is right, for the stats on reaction times tell us otherwise: we are for the most part on autopilot.
The news gets even worse for the Platonists among us. In the 1970s, Benjamin Libet, a physiologist at the University of California, conducted a famous series of experiments that has tormented many a scientist and philosopher. These experiments were simplicity itself. Libet wired up a group of participants with what are called EEG leads, small monitors attached to the scalp which record the electrical activity in the brain, and then asked them to make a decision to do something, like lift a finger. What he found was that the participants’ brains were preparing the action 300 milliseconds before they actually made the decision to lift their finger. In other words, their conscious decision to move came almost one third of a second after their brain had initiated the movement.
Consciousness, these experiments suggested, is merely a bystander observing a decision already taken, almost like watching ourselves on video. Scientists and philosophers have proposed many interpretations of these findings, one of which is that the role of consciousness may not be so much to choose and initiate actions, but rather to observe decisions made and veto them, if need be, before they are put into effect, much as we do when we practise self-control by stifling inappropriate emotional or instinctive urges. (We may be on autopilot for much of the day, but that does not mean we cannot take responsibility for our actions.) Libet’s experiments, suggesting as they do that consciousness is largely an override mechanism, led one particularly witty commentator, the Indian neuroscientist V.S. Ramachandran, to conclude that we do not in fact have free will; what we have is free won’t.
It seems that consciousness is a small tip of a large iceberg. But what exactly lies below it? What lurks beneath our rational, conscious selves? The eighteenth-century German philosopher Immanuel Kant proposed a particularly intriguing answer to this question: we do not know what is down there. Kant believed that our consciousness – that is, our experience of a unified and understandable world, and of a continuing person experiencing this world – is possible only because our mind constructs this unified experience. If our mind did not organise our sensations the world would be a whirling, blooming confusion. But the mind does: it provides organising constructs, such as space and time, so that we experience a continuing world, just as it does another construct, that of cause and effect, which ties succeeding events together into a coherent story. Kant thought all these unifying constructs applied only to the veil of sensations, and not to the entities creating or lying behind the sensations. These objects we can never know. Inaccessible to rational analysis, forever mysterious to science, these hidden beings can be groped at and suggestively discerned only through art and religion. And it is in this dark world that the soul belongs, putting it too beyond the ken of rationality and beyond the domain of cause and effect. It was upon this argument that Kant rested his belief in free will.
Kant’s philosophy left a deep imprint on German thought. Freud, inspired by Kant’s vision, argued that below the façade of our rational selves, deep in our subconscious, there boils a devil’s cauldron of envy and sexual perversion and patricidal tendencies which warps our judgement. Nietzsche too found