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

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frequencies as they come on air, has a head start over one that was built on the assumption that its world would last for ever. The ability of an individual to learn a new pattern, and a new trick to cope with it, is, one of the most amazing discoveries of evolution, but it needs, if it is to work, adequate resourcing.

      This is the second good reason for having a brain. A nervous system intricate enough to co-ordinate a wide range of pressures and resources makes a good basis for the next great evolutionary jump: incorporating a degree of flexibility into these interconnections, so that the way they are wired up can (within limits) respond to the success of the system in promoting the individual’s (and her children’s) survival. If it is useful to be born knowing what to do when you see a snake, it is even more useful to be able to record the kinds of situations in which you personally have met snakes before, and to be able recognize a fresh trail, and the distinctive way the grass moves. From the point of view of this book, the brain will be the most interesting of the body’s intelligent subsystems precisely because it is the one that is tuned so comprehensively by experience—and therefore by culture. Muscles and antibodies too are affected by what happens to them, but to nothing like the same extraordinary extent.

      The Brain’s Priorities

      The brain is the centre where information gathered by the rest of the nervous system, about the state of things both inside and outside the body, is collated and integrated. It is the ‘General Communications Head-Quarters’ of the body. Information continually arrives along all the neural pathways, coded as patterns of electrical impulses. The eyes, ears, tongue and nose bring news of what is happening offshore. Internal monitoring stations tell of the level of blood sugar, the fullness of the bladder, the oxygen/carbon dioxide balance in the lungs, the acidity of the gastric juices…and a hundred other indices of the well-being, or the imminence of required action, in different parts of town. The lookouts have just sighted something – is it the long-awaited supply of fresh meat, or is it that marauding pirate? The miller has more corn to grind than he can cope with: is the store-house full or not? The garbage disposal operatives say it is time to take a dump. The power-station workers are complaining because they have missed their tea-break…All these different ‘interests’ make claims on the attention and orientation of the community as a whole. Cases must be heard, priorities decided, less urgent needs postponed, plans of action prepared.

      For example, receptors in the skin, the joints and the muscles tell of aches and pains, pricks and tickles, and update the story about where the limbs are, so that when you need to move, perhaps in an emergency, you already have information about where ‘here’ is, and can therefore compute the arm movement required to get from ‘here’ to ‘there’. A baby reaching for a toy makes a ‘ballistic swipe’: it throws out the hand like a harpoon fired from a ship. If the toy is moved after the movement is started, there is nothing she can do to correct the movement in mid-air. But an older child, whose monitoring of body states and dynamics is more developed, can change the direction of reach immediately. Her hand is now not a simple projectile but a toy-seeking missile, locked on to the target in a much more subtle and responsive fashion. She has learnt how to link the sight of the toy, the sight of her arm, the feel of the arm as it is moving, and the muscular commands that control the arm movement, in a flexible way.

      

      In this chapter I have explained the evolutionary value of plastic brains, and illustrated some of the different jobs that they may be called upon to do. And we have seen how the design function of a brain gets more complicated as the sophistication and differentiation of its body increases. We have developed an overview of what the brain does. But in order to understand it in more detail, we need also to be able to talk about what it is: what it is like, and how it does what it needs to do in order to fulfil its role. This is the subject of the next chapter.

       FOUR The Self-Organizing Organizer

      The cardinal background principle for the theorist is that there are no homunculi. There is no little person in the brain who ‘sees’ an inner television screen, ‘hears’ an inner voice, ‘reads’ the topographical maps, weighs reasons, decides actions and so forth. There are just neurons and their connections. When a person sees, it is because neurons, individually blind and individually stupid neurons, are collectively orchestrated in the appropriate manner…In a relaxed mood we still understand perceiving, thinking, control and so forth, on the model of a self – a clever self – that does the perceiving, thinking and controlling. It takes effort to remember that the cleverness of the brain is explained not by the cleverness of a self but by the functioning of the neuronal machine that is the brain…In one’s own case, of course, it seems quite shocking that one’s cleverness should be the outcome of well-orchestrated stupidity.

       Patricia Churchland23

      

      Since man is above all future-making, he is, above all, a swarm of hopes and fears.

       J. Ortega y Gasset

      Brain-Mind language

      If we talk about the workings of minds in the language of commonsense, we can consider the kinds of important, human things that we want to consider—hopes, fears, aspirations, experience. But in doing so we have to take the concepts of everyday language on trust. If there is something wrong with the assumptions about the mind that are built in to, these categories and idioms, no amount of vernacular talk will reveal it. Our familiar ‘mind-language’ is too suspect; if we rely on it we may be inadvertently begging the most crucial questions.

      On the other hand ‘brain-language’, the neuroscientists’ vocabulary of neurons and synapses, enzymes and axons, is not up to the job either. It may be ‘sounder’ in some ways, but it is simply too low level, too fine-grain, to enable us to discuss the issues we need to discuss. Human beings are systems, and one of the things this means is that they have properties at ‘higher’ levels of organization that are not predictable or explicable in terms of the properties of ‘lower’ levels. At each level of discourse one needs a new language for talking about ‘wholes’, a language which builds on the language of ‘parts’, but which can say things that the language of parts cannot.

      (This incidentally is the reason why currently fashionable attempts to talk about, or worse to ‘explain’, consciousness in terms of the language and phenomena of quantum physics – or any other kind of physics, come to that – are nothing short of ridiculous. While claiming to be based in ‘new paradigm’ thinking, they are in fact reductionism ad absurdum. The parallel between the (presumed) ‘free will’ of human beings and the ‘indeterminacy’ of fundamental particles is of no more interest or significance than a pun like Thomas Grey’s ‘They went and told the sexton, and the sexton toll’d the bell’. It is the basis of a cheap joke, not of a serious intellectual conversation. The sciences of nuclear physics, chemistry, biochemistry, genetics, neurophysiology, cognitive psychology, sociology, anthropology and cosmology are distinct, and hierarchically arranged, for very good reasons. Each attempts to find the best language for talking about a particular level of organization within the cosmic system as a whole, and to do so it must pay attention to what the people working in the next layer up and the next layer down are also saying. But to jumble up the language of quarks and the language of consciousness is just conceptual vandalism.)

      To talk of the brain is to talk in a dialect that is vital to builders – brick-laying and plumbing, foundations and joists – but which is quite unequal to the needs and interests of an interior designer, who uses a vocabulary of spaces, functions, aesthetics and style; a language of human purpose and desire. ‘Brain’ is builder language for one specialized part of the body. ‘Mind’ is designer language for the functions that the brain carries out.

      An architect needs to be bi-lingual: she has to be able to talk to both electricians and designers in the language that is appropriate to the concerns

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