The Hour Between Dog and Wolf: Risk-taking, Gut Feelings and the Biology of Boom and Bust. John Coates

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      Fig. 5. The visual system. Visual images travel by electrical impulses projected from the retina to the visual cortex at the back of the brain. They are then sent forward along the ‘what’ stream, which identifies the object, and the ‘where’ stream, which identifies its location and movement. An older, faster route for visual signals travels down to the superior colliculus where fast-moving objects can be tracked.

      To what features of the world do we pre-attend? When a close fielder is crouched at the ready, frozen like a statue, his eyes fixed and unable to scan, what in his visual field captures the interest of his pre-conscious processor? We do not yet know a complete answer to this question, but we do know a few things. We attend pre-consciously, as in blindsight, to moving objects, especially animate ones. We attend to images of certain primitive threats, such as snakes and spiders. And we are strongly biased to aurally attend to human voices, and visually to faces, especially ones expressing negative emotions such as fear or anger. All these objects can be registered so rapidly, in as little as 15 milliseconds (this does not include a motor response, of course), that they can affect our thinking and moods without our even being aware of them. In fact we often know whether we like or dislike something or someone well before we even know what or who it is. The speed and power of pre-conscious images, especially sexual ones, were once used in subliminal advertising as a way of biasing our subsequent spending decisions. More usefully, this pre-conscious processing can affect motor commands for reflex actions and automatic behaviours.

      One of these reflexes is our startle response, a quick and involuntary contraction of muscles designed to withdraw us, like an escaping octopus, from a sudden threat. It can be initiated by both sights and sounds. A loud bang will trigger the startle, as will a rapidly approaching object in our visual field. The way we visually detect an object on a collision course with us is ingenious: our startle is initiated by a symmetrical expansion of a shadow in our visual field. The expanding shadow indicates an incoming object, and its symmetry indicates that it is heading straight for us. Apparently this pre-conscious object tracking is so well calibrated that if the shadow is expanding asymmetrically our brain can tell within five degrees that the object will miss us, and as a result the startle response is not triggered. The startle, from sensory stimulus to muscle contraction, is exceptionally fast, your head reacting in as little as 70 milliseconds and your torso, since it is farther from your brain, in about 100 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.’

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