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Adrian’s achievement

Edgar Douglas Adrian (1889–1977) was a much younger contemporary of Sherrington, with whom he shared the Nobel Prize in 1932. Adrian’s work is in certain respects complementary to Sherrington’s, for it gives an account of the electrical activity in both motor and sensory nerve fibres that accompany reflex and other integrative actions of the nervous system. Adrian showed that there is only one kind of action potential in nerve fibres, no matter whether these are motor or sensory ones. Furthermore, he showed that the force of contraction and the intensity of sensation are graded as a consequence of different frequencies of action potential firing in the nerves as well as changes in the number of nerve fibres that are firing. He later turned his attention to the origins of electrical oscillations in the brain, and established that the Berger rhythm comes from the occipital part of the cortex.

His reluctance to speculate

The question ‘How is the brain related to the mind?’ puzzled Adrian no less than it puzzled others. But, unlike Sherrington, he was disinclined to speculate upon the nature of the mind, or upon the question of how brain activities are related to mental phenomena. His reflections on such questions are therefore relatively few, and expressed with considerable caution. Nevertheless, it is worth surveying them briefly, for they raise questions that still bewilder neuroscientists. Though Adrian did not commit himself to Cartesian dualism, Cartesian elements do creep into his cautious and tentative remarks, as we shall see.

The ‘man-machine’ and the ego

In his lecture on consciousness in 1965, Adrian observed that, in general, natural scientists prefer to remain uncommitted on such questions as the relationship between mind and matter. However, he admitted, it is difficult for physiologists to maintain such Olympian detachment. Any neuroscientist concerned with studying the sense-organs and the central nervous system can hardly avoid the problems that have always arisen in trying to relate physical events and activities in the body to mental activities. The problem can be put most starkly by reflecting on the fact that one might, according to Adrian, build a mechanical human being that behaved exactly as we do. For the ‘universal Turing machine’, he observed wittily, can ‘turn its band to any problem’, and a ‘man-machine’ might be programmed to do anything we can do. What would be missing, however, ‘is ourself, our ego, the I who does the perceiving and the thinking and acting, the person who is conscious and aware of his identity and his surroundings’.⁹ We are convinced, Adrian remarked, that we have an immediate awareness of ourselves, and that this is one thing that a machine could not copy.

Adrian’s hesitant Cartesianism

This thought is, to be sure, Cartesian through and through. What differentiates man from mechanical animate nature is, according to Descartes, consciousness. Descartes assimilated consciousness to self-consciousness in one sense of the latter term. For he held that thought, which is the essential attribute of mind, is defined as ‘everything which we are aware of as happening within us, in so far as we have an awareness of it’. Notoriously, Descartes held that the foundation of all knowledge was each person’s consciousness of his own thoughts, and hence his indubitable knowledge of his own existence. In this respect, Adrian followed Descartes. For, he observed,

I used to regard the gulf between mind and matter as an innate belief. I am quite ready now to admit that I may have acquired it at school or later. But I find it more difficult to regard my ego as having such a second-hand basis. I am much more certain that I exist than that mind and matter are different.

Apart from those who are insane, ‘out of their mind’, one does not come across people who do not believe in their own individuality, though there are many who do not believe in the separation of mind and matter. Belief in one’s own existence seems to depend very little on deliberate instruction.¹⁰

Moreover, Adrian continued, ‘in the study of the human ego, introspections are almost all we have to guide us’. ‘Introspections’, presumably, reveal to us the sensory, perceptual and emotional contents of consciousness. This (mis)conception conforms with the venerable philosophical tradition that stems from Descartes and the British empiricists. It is a general (mis)conception that is still characteristic of much neuroscientific reflection on these matters, especially among those neuroscientists who think that ‘qualia’ are the mark of conscious life – a feature that seems irreducibly ‘mental’ (for a detailed discussion of qualia, see §§11.3–11.3.5).

Adrian’s confusions about the ego

Adrian was exceedingly hesitant to commit himself to any firm doctrine concerning the nature of what he called ‘our ego’. He quoted the neurologist Francis Schiller, who claimed in 1951 that consciousness is a ‘logical construction’, and the ego ‘a convenient abbreviation, an abstract of the multiplicity of objects from which it is developed’ – this, Adrian averred, ‘seems to me a reasonable position to have reached’.¹¹ For, he thought, ‘the physiologist is not forced to reject the old fashioned picture of himself as a conscious individual with a will of his own’, for the view embraced acknowledges some kind of validity to the introspective as well as to the physiological account, while admitting that the two are incompatible. What that implies, Adrian claimed, is that in the fullness of time the two accounts will have to be reconciled. So it would, he held, be absurd to suppose that the scientific account will not be altered.

It is noteworthy that this (essentially Russellian) conception is actually at odds with the Cartesian view of the ego of which Adrian previously approved. It is probable that Adrian had no clear grasp of the Russellian term of art ‘logical construction’. For if consciousness is a logical construction and the ego a convenient abbreviation, then the immediate awareness of the self that Adrian endorses is as much of an illusion as an immediate acquaintance with the average man (the average man being uncontroversially a logical construction). Confusions concerning the ‘ego’ and the ‘self’ will concern us in chapter 14.