Noises from the Darkroom: The Science and Mystery of the Mind. Guy Claxton

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СКАЧАТЬ discussion…represents my attempt to be rid once and for all of the little man inside the skull who approves of some sensory events relayed to him by the nervous system, disapproves of others, and guides behaviour accordingly…By some such approach as the one suggested, it may be possible to understand the directedness and order in behaviour, and the variability of motivation, as produced by neural functioning alone.²⁶

      And Francisco Varela of the Ecole Polytechnique in Paris is of the same mind:

      Each component operates only in its local environment…but because of the system’s network constitution, there is a global co-operation which spontaneously emerges…In such a system…there is no need for a central processing unit to guide the entire operation.²⁷

      As Patricia Churchland points out (in the quotation at the beginning of this chapter), however, this leaves us with some explaining to do when we come to consider the prevalent sense that we all have that there is some instigator behind the eyes, with whom we are rather closely identified, who can override what is going on and impose its ‘will’ on the rest of the brain/body system.

      One latent misunderstanding that the octopus analogy might induce needs to be scotched straight away. The ideas of ‘awake’ and ‘asleep’ simple translate in brain terms as ‘switched on’ or ‘activated’, and ‘unactivated’, or ‘dormant’. An awake octopus is one whose connections and characteristics are currently instrumental in determining where the activation or the ‘energy’ in the network flows next. A dormant octopus is one who is not currently involved. There are no implications in this model about consciousness. The pattern of awake octopuses has nothing (so far) to do with what is conscious. As we shall see later, what enters consciousness is often only very distantly related to what is going on ‘behind the scenes’ in the octopus disco-land of the brain-mind.

      The Continuum of Attention

      As well as the location of the activation varying, we might also notice changes in its concentration. At some times, and in some areas, the pattern of pink bodies might be very tight and clear-cut. At others, it might be much more diffuse. And at some times the flow of energy is likely to be quick, clear and unambiguous; at others, where the trails are less well defined, or when a mistake might prove costly, then the kaleidoscope of patterns may shift more slowly, and there is more time for activation to accumulate in a particular area, and for different by-ways or shades of meaning to be ‘explored’. Not that there is anyone or anything which is ‘deciding’ to explore. It is simply in the nature of the network sometimes to run fast and deep, and at other times to behave like a stream which comes to a hollow and ‘waits’ for the bowl to fill into a small pool before it can overflow and run on again.

      We might contrast two extreme modes of attention; one focused, sharp and ‘serial’, with each thought or sensation following another in clear order; the second broad, diffuse and ‘parallel’ or ‘holistic’. The first would be like a spotlight with a narrow beam; the second like a floodlight or a candle. Each, we might note, has its uses. There are situations in which we would prefer the candle: finding our way around a pitch-black cave, for example. The candle, casting a broad light, would enable us to get our bearings much more effectively than the spotlight, whose beam, illuminating only one tiny part of the whole cave at a time, would tell us, at this stage, too much about too little. But if the candle-light enabled us to pick out an object of interest – a carved stone, say, or a parchment scroll – then we might find its all-round light too dim for close inspection, and we would thankfully switch on the intense, tight beam of the torch, to investigate in detail.

      So it is with these two extremes of activation in the brain. Sometimes it serves us best to take it slowly, to allow the shadows and ambiguity to remain while a ‘felt sense’ (an idea borrowed from psychotherapy) of the situation as a whole is allowed to form. If the need for action is not urgent, we can, so to speak, prevent a ‘solution’ from crystallizing quickly, raise the thresholds of the ‘action units’, and allow the pool of activation to build up in one area of the network. By doing so, new options and connections may become apparent whose discovery had been prevented by the normal fast run-off of activity down the first familiar trail. The brain, in other words, has it in its constitution to offer reflection, a kind of leisurely exploration of latent possibilities, unhassled and undirected by the need to find an answer to a pressing predicament.

      And the brain can also operate at the other extreme. When the demands of the situation are saying: ‘Don’t just stand there, do something’, the brain can usually oblige. It can compute very quickly the tongue-flick required to catch the fly, or the top-spin lob that might win the point. When the front tyre of your bicycle hits a slippery man-hole cover as you are going round a corner, lightning calculation and correction may, if you are lucky, keep you in the saddle – again without the help, or even the presence, of the normal conscious commentary, which may be paralysed with fear while the brain/body is fighting for its life.

      We might guess that the more complex and delicate the computations, and the more long-term rather than immediate the goals to which they relate, the more useful, the more frequently appropriate the diffuse, reflective mode would be. Yet we might also ponder on the plight of an animal, awash with goals, projects, interests and desires, in an intricate environment replete with opportunities but also dangers, who has become locked in to the quick-sharp way of operating; who finds itself in a blacked-out cavern, full of tantalizing smells, unfamiliar protuberances and ominous noises, equipped only with a torch that gives a light spot the size of a pea. I shall argue later that people in modern industrialized societies are in precisely that position.

      One salient difference between the diffuse/holistic and the focused/analytic modes of processing is in the picture they give of the world. The focused mode shows you objects only one, or maybe only one piece or aspect, at a time. Individual figures stand starkly out from the ground. It is like having to do a 1000 piece jigsaw puzzle without having access to the picture on the lid of the box. Small details or objects seem to be self-existent; if they have a life it is a life of their own, and any overall sense of relationship, of the ecology of the situation, has to be painstakingly constructed with the help of memory, rather than, as with the candle, apprehended as a whole. Diffuse processing, on the other hand, gives an ecological view; it leaves out detail, but conveys a sense of the relationship between ‘figure’ and ‘ground’, to use Gestalt psychologists’ terms.

      How the Brain Behaves

      Some of the most general features of human psychology arise simply from the nature of the brain-mind system – without our having to add any other assumptions. It is obvious, for example, that such brains are built to generalize and categorize in the same way that humans do. Experience wears metaphorical ‘grooves’ in the brain, as a river gradually wears a V-shaped valley through the landscape. And just as rain falling on the sides of the valley tends to run down into the river, so experiences that share most, but not all, of the features of a very common category will tend to be treated as if they were typical members of the category.²⁸ If it has got soft fur, likes fish, mews and rubs itself along my legs at supper time – well, that’s good enough for me: it’s a cat. It may only have three legs, be at least six inches longer than any other cat I’ve ever seen, and have fur the colour of the sky…OK, it’s a lame, gross, exotic cat – but still, basically, a cat.

      Psychological research since the turn of the century has been full of demonstrations – if we needed them – that we see what we know; we look at the world through the categories and concepts of our minds. In one of the most famous demonstrations, people were flashed very brief exposures of playing cards which they were asked to try and identify. Unbeknownst СКАЧАТЬ