The neuropsychological question (the easy one) is how? How do the aforementioned 1,500 grey, soggy grams of dense nervous tissue produce consciousness? How may consciousness arise? This is a relatively straightforward question and will be answered, in outline, one day, possibly fairly soon. It is ‘merely’ a question of wiring and procedures. With steadily improving investigative tools neurologists will eventually solve it. Much theory already exists (e.g. Cotterill 1997, Crick 1994, Edelman & Tononi 2000, Greenfield 1995 & 1998, Newman 1997, Nørretranders 1998, Parvizi & Damasio 2001, Smith & Jokic 2003, Wegner 2002).

Many neuropsychologists envisage consciousness as feedback (e.g. Crick 1994, Damasio 2000, Edelman & Tononi 2000, Greenfield 1995 & 1998, Newman 1997). They suggest that some of what is going on in the unconscious reverberates around feedback loop circuits and is, somehow, re-presented to the mind which therefore re-experiences something it has just experienced unconsciously. This re-experiencing is thought to be the event of which we become conscious, the mental event of which we become consciously aware. (Whatever that means – we must, philosophically speaking, take care. There is no Cartesian ‘theatre’ in your head where you sit watching consciousness roll. There is no ‘you’, separate from your mind, to watch it. The tiny homunculus, who used to be envisaged sitting in the mind and ‘seeing’ what was going on in there, does not exist. There is ‘just’ the mind, or the mind-event. There is no-one to experience it, only the experience itself. Very Zen. Consciousness is also nowhere in particular – there is no ‘seat of consciousness’ in the brain – it is probably more a matter of degrees of excitation, particular states of arousal, wherever that activity may, for the moment, be taking place.) In the words of Greenfield, consciousness may be mediated through

‘...shifting populations of neuronal networks...’ (1995 p. 34) such that it is ‘...spatially multiple yet effectively single at any one time. It is an emergent property of non-committed and divergent groups of neurons that is continuously variable with respect to and always entailing a stimulus epicenter.’ (ibid. p. 97).

There is no specific site of consciousness, which is instead a phenomenon of widespread excitation of networks which are ‘non committed’ – you can be conscious of almost anything, almost anywhere in your cortex where relevant excitation occurs, and may become conscious of many aspects of whatever the original ‘stimulus epicenter’ was.

A popular candidate for the actual machinery of the postulated feedback system is the reticular activating system projecting basic information from brainstem to thalamus and thence the extensive mesh of loops which are known to project both ways between the thalamus and the cerebral cortex, especially the frontal cortex. (e.g. Damasio 2000, Edelman & Tononi 2000, Newman 1997, Parvizi & Damasio 2001) Perhaps mental activities in the cortex are fed back to the thalamus, modified again there and re-projected to the cortex. At any rate, we are speculatively envisaging a reverberating, re-experience experience; material from the unconscious passing round feedback loops and reappearing within the cortex as a new set of stimuli, perhaps amplified stimuli, and, perhaps as a result of this amplification, now consciously experienced stimuli. The whole process probably remains under unconscious direction and control. If the conscious has a purpose, it is probably directed to it unconsciously – the unconscious may, in other words, ask the conscious to carry out work but it may be work the unconscious has decided to have done for its own, eternally inscrutable purposes (e.g. the allocation of attention & see Reimer 2006). Perhaps my unconscious is the real ‘me’ and uses my conscious as if it were a torch, to illuminate anything it wants a second or better or particular kind of look at? It is, in yet other words, entirely possible that the conscious is very much the junior partner in such collaboration. It is also entirely possible that it is not called into action all the time – there may be periods when we are, in effect, simply zombies, simply A conscious, being ‘run’ entirely by what I am calling our unconscious. (Do you ever have that ‘how did I get here?’ experience?) (And see Goldberg et al 2006.)

That was a preliminary stab at the easy question. The answers, should they ever materialise, will be fascinating. They will not, though, answer our hard question, which is why? What is consciousness for? What does it do?

At first glance this seems a daft question. It seems perfectly self-evident that ‘I’ am in complete control, if not of my feelings at least of my thoughts and actions. This ‘I’ who is so in control is, naturally, my conscious, aware self. It seems preposterous, perhaps even pointless, to question the belief I have lived with for so long, so successfully and for which I seem to have such incontrovertible, if circumstantial, evidence. We feel as if we live within our P conscious which is, by definition, the only mental activity of which we are aware. Because of this we see all intellectual activity as conscious activity, consciously managed. If we think about it at all we envisage the unconscious as managing all the low level, automatic, A consciousness stuff – enabling us to walk and chew gum at the same time, for example. We imagine all our real thinking, all thinking of much value, is done within our conscious. How could it be otherwise, we cry?