Neuropolis: A Brain Science Survival Guide. Robert Newman

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СКАЧАТЬ interrogators who try to browbeat and bamboozle a private soldier out of making a complaint against senior officer. You didn’t see what you think you saw. They didn’t say what you think you heard them say. You weren’t even where you think you were when you saw what you thought you saw.

      Why is there nothing not something?

      For thousands of years one of the fundamental philosophical questions has been why is there something not nothing? With Eagleman we find ourselves in the strange position of asking why is there nothing not something? Why would the objects of the world have no texture, no taste, no sound, no smell – rather than something, anything, even if different from what we think? Why none at all? I could understand if he was saying everything was mauve, had the texture of tulip petals, and the taste of ash, but why sans taste, sans everything? This goes far beyond Berkeley, for whom the things of the earth, even though they depend on being perceived for their existence, are eternally real because forever under God’s good gaze.

      To answer to the question ‘why is there nothing not something in Eagleman’s philosophy?’ we need to look at what is real for him. What is still standing once he has razed the outside world? And the answer, it turns out, is: wavelength frequencies.

      The blueness of a Japanese lizard’s tail is an illusion entertained by the weasel, the snake and me. What is not an illusion, however, what is in fact irrefutable is the electronvolt energy value of the light bouncing off its tail. Why are wavelengths true but not a lizard’s bright blue tail? It is, I suggest, because we have left the real word of science for the virtual world of Neuropolis, where, inscribed above the city gates, is that great motto of scientism:

      All science is either physics or stamp-collecting.

But Ernest Rutherford’s boorish remark is false. All science is not physics. If you want to find out how lizards are tricking weasels into attacking tails not heads, an isotopic triaxial probe is simply the wrong tool for the job, because the job isn’t about measuring electromagnetic frequency. The job is ecological, and ‘ecological events must be distinguished from microphysical and astronomical events.’*

* James Gibson, The Ecological Theory of Visual Perception, 1986.

      It’s a question of scale, as much as anything else. Microphysics might accurately describe a stream as atoms colliding, or wavelengths oscillating, but when we wade barefoot across the stream our experience isn’t an experience of atoms and electromagnetic wavelengths. We experience wetness and cold. The stream’s pebbles are treacherously slippy, with a sort of slime on them, and wedge the feet bones apart in a surprisingly painful way.

      Are these merely subjective impressions when what science demands are objective measurements? Not if science demands an accurate description of animal interacting with environment. If that’s what we want then an accurate description must be at the ecological level. That is the appropriate level for the job in hand, since our lives are lived at the ecological scale – not among the celestial objects of astronomy or the neutrons of the microphysical realm, ‘but in the very world’, as Wordsworth wrote,

      which is the world

      Of all of us, – the place where in the end

We find our happiness, or not at all!*

* William Wordsworth, ‘The French Revolution as It Appeared to Enthusiasts at Its Commencement’, The Prelude, 1805.

      Austerity on the brain

      For David Eagleman, austerity is deeply woven into the fabric of nature. It is not an invention of humans, as he believes colour to be, but intrinsic to matter, to reality. Not only is nature austere as in grey and dour (a claim we examined earlier) nature is also austere as in pinched, frugal, economizing. Eagleman doesn’t apply austerity measures to the living world, he just discovers that the living world proceeds according to austerity principles. It turns out that organs such as the brain, for example, conduct a thorough review of all non-essential services:

      So why doesn’t the brain give us the full picture? Because brains are expensive energy-wise… brains try to operate in the most energy-efficient way possible.

      I know energy-efficiency would seem to be something you might expect from a clever organ like the brain, but, for better or worse, that appears not to be the case. Whereas a smart electrical appliance, for example, powers down when not being used, our brains are more active when we sleep.

One of the most wonderful features about how the brain works, in fact, is the sheer extravagance of neural activity, its superabundance. The technical term used to describe the synaptic proliferation that characterises early brain development is ‘exuberant synaptogenesis’. In the landmark paper ‘The Physiology of Perception’, Walter J. Freeman and his colleagues found that ‘perception depends on the simultaneous, cooperative activity of millions of neurons spread throughout expanses of the cortex.’*

* Walter J. Freeman, ‘The Physiology of Perception’, Scientific American, 1991.

      Not exactly a slimmed-down organization. A rationaliser seeking ambitious saving targets would ruthlessly downsize such a sprawling operation, and would also take the axe to this sort of spare capacity:

vast collections of neurons … shift abruptly from one complex activity pattern to another in response to the smallest of inputs.*

* ‘Walter J. Freeman, ‘The Physiology of Perception’, Scientific American, 1991.

      We are told every day that public sector social services should be streamlined. This is dunned into us with such monotony that it begins to look like a Law o’ Nature, rather than one political choice among many other possible ones. Defunct economic dogma does not apply to how the brain works. Whatever the political and economic weather the brain continues its extraordinarily successful policy of being extremely unstreamlined. Just take a look at the Spanish practices going on in entorhinal cortex.

      The entorhinal is famous for spatial navigation and memory. Two paths – lateral and medial – lead from the entorhinal to Memory Central in the hippocampus. The lateral path is for spatial navigation ‘Where am I?’ and the medial for memory ‘What happened?’ Management consultants, who make it their business to rationalise a firm to its knees, have a horror of what they call ‘duplication of function’, but I’m afraid that’s what we have here. In a regrettable recidivism, wholly ignorant of best practice guidelines (helpfully supplied by Goldman Sachs) and the harsh new economic realities (also helpfully supplied by Goldman Sachs) the brain simply refuses to ‘operate in the most energy-efficient way possible’. I blame the unions.

      The only time the entorhinal cortex is not guilty of ‘duplication of function’ is when it is busily triplicating. It’s not enough for the entorhinal cortex just to check sense data from the hands against data from the eyes, it also insists on cross-checking with the middle ear, in a process called reentrant mapping. Here we have unforgivable ‘triplication of function’. Yet it all works very well, and has done since before records began.

      Now it is true that bodies need to conserve energy. But the reason the brain doesn’t give us the full picture has little to do with СКАЧАТЬ