LITMIR.BIZ

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history of who has woken up whom in the past. And conversely an individual input can ‘set’ whole areas of the community to be either more or less sensitive to what happens next.

      Resources and Attention

      Another important feature of this model is that the total wakefulness of the community – the overall ‘amount’ of activation available to the system at any moment – is finite. If there were no sources of inhibition as well as activation, the octopuses could wake each other up until they were all wide awake at once. Clearly such an eventuality has to be prevented: it would put us in a state of cortical meltdown – a condition of total perceptual and behavioural freak-out. Everything would be ‘On’, but we would be incapable of being appropriate. The beauty of the system of checks and balances built in to the fabric of the octopus colony is that it becomes, of its very nature, selective and integrative. The colony as a whole has to choose and moderate amongst what is going on.

      This is not to say that the total level of activation is always fixed. If you looked down from your helicopter and counted the pink bodies, there would not always be exactly the same number. Sometimes the total might be a bit greater, sometimes a bit less, but the important point is that the total is relatively fixed, and is certainly finite. It cannot explode, though it may vary somewhat as a reflection of the overall state of ‘alertness’ of the system.

      In fact, though, there is a very important source of variability in the effective amount of energy that the system has at its disposal, independent of variations in the total energy available. Imagine that, when a particular gang of octopuses, A, is awake, one of its ‘jobs’ is to send a constant low-level tickle (or massage) to a variety of other gangs or individuals, B, C and so on. In addition, suppose that A is able to stay awake for long periods of time. These continuous ‘trickles’ of excitation and inhibition will make a network with one set of connections respond as if it were a network with a different pattern of strengths. The crucial difference, however, between the effect of priming, and the long-term change in the strengths of the connections, is that, in the former case, it is possible for the priming overlay to be removed. If A were turned off, even for just a few moments, there would be an instantaneous, apparently ‘magical’ reorganization, perhaps a re-prioritization, of the brain system as a whole. What had always been ‘at the back of one’s mind’, or ‘on the tip of one’s tongue’, now would no longer be there, or would stand out with unfamiliar clarity.

      And in this hypothetical situation there would be another interesting effect as well. While unit A has been ‘on’, it has not only been keeping particular other units or groups of units on a hair trigger; it has in so doing been keeping tied up some proportion, perhaps a significant proportion, of the total activation permitted in the brain. If there is only so much energy available at any time, then if 10 per cent of it has to be dedicated to certain locations to keep them primed, there is less available – less ‘free energy’, we might say – to underwrite the activity of the rest of the system. And the less free energy there is, the more crude or stereotyped we might imagine the response of the system to be. Only those octopuses with the lowest thresholds, and the biggest and most numerous inputs, get woken up. (This option, for the brain to change its way of operating by tying up some of its total pool of activity, will become very important later when we try to explain the phenomena of mystical experience.)

      The Brain with No Self

      In the octopus colony there is no privileged group with special status or special powers. Just as the brain as a whole has to be seen as a subsystem of the whole body, so each octopus gang must be seen as a member of a participative democracy. What happens in the brain, and the momentary conjunction of priorities, interpretations and actions that it is involved in computing, arise naturally and uniquely from the state of the system as a whole – brain, body and world.

      Many of those who have been working in the area of neuroscience have made it very clear that their object is to see just how much of human functioning can be accounted for without recourse to any ‘ghost in the machine’. How far can we get before we have to call upon ‘the self? Could it be that we can even get all the way: that the hypothetical ring-master or engine-driver, the personal ‘I’, is not actually in control; that the biology, when it comes down to it, does the lot? Donald Hebb, the Godfather of neuroscience, was in no doubt:

      This 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.

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