Life of brain
Randal A. Koene’s article “How to copy a brain” was a blast from the past, with its implicit assumption that neurons are all that matters when it comes to the basis of “mind”, and that associated computations are primarily digital (27 October, p 26). In fact, we now know that we should be thinking in terms of systems that include both neurons and astrocyte cells.
Humans have about twice as many astrocytes as neurons, and by comparison, C. elegans nematodes have at least five neurons per astrocyte. The principal computations are likely to be analogue.
The article asks, “What will life be like for human minds embodied in non-biological materials?” The answer is “probably nothing”, since we know even less about what underlies consciousness than we do about what is at the basis of “mind”. The road ahead will lead us into landscapes that we can only begin to envisage.
“Continuity of self could be assured, despite minds having novel embodiments,” writes Koene. Perhaps we can overcome the difficulty of capturing the state of a brain without dumping so much energy into it that we disturb it radically. We might ignore the fact that neurons die off in quite unpredictable ways not susceptible to modelling – such as when I can’t recall the name of Aunt Jemima’s cat, for example. We could set aside the issue that a brain is not a closed system, but reacts to the nutrients, hormones, alcohol and other drugs in which it is bathed.
That leaves the issue of chaos. The brain is surely a richly interconnected system, riddled with feedbacks. It is self-modifying, reprogramming itself daily. All hope of determinism and predictability is doomed.
Still, suppose that we transcribe a brain into an emulator, and for convenience assume that the original person promptly dies. We can live contentedly with the fact that we cannot predict the emulator’s actions, for the same was true of the person.
But what if, in a moment of ill-considered mischief, we make a second copy?
If the twin emulators are truly brain-like, their thoughts, actions, decisions and characters will slowly but surely diverge. Which, then, is the true continuation of the original self?
Great Missenden, Buckinghamshire, UK
Ending cancer
The promising new treatments for cancer that you describe are good news (13 October, p 38). However, such treatments have inherent limitations because they are based on a fundamentally mistaken view of cancer centred on the role of individual genes.
This prevents true understanding of how cancer develops and how it can be cured. One problem is that many of the same genes said to cause cancer are also involved in healthy development.
Consideration of genes alone cannot reveal the cause of the phenotypes that distinguish cancers from normal developing tissue. That means we are still treating the effects and not the causes of cancer.
In a monograph published last year, I presented a new paradigm of how cancer works (). Genes make up less than 5 per cent of the human genome. The other 95 per cent is non-coding. The causes of cancer are networks in the non-coding genome that are interpreted and executed by cells, much like computer programs.
I demonstrate how these networks control the growth of tumours and their spread to other tissue. The monograph describes and classifies all possible cancers in a kind of periodic table of thousands of different cancer networks. Modelling and simulating these networks gives us a new perspective and explanation of how cancer works – and of how to change the networks that control the cancer and stop tumour growth. This theory is a radical departure from gene-centred views of cancer.
We now have to discover how cancer networks are implemented at the molecular level. Then we will be able to develop new technologies to diagnose, treat and cure cancer.
Fear of dying
Shelley Kagan’s article about death is for the most part a bracing response to our fears, but as a British citizen of a certain age I have my reservations about the statement: “One thing you might worry about is the process of dying” (20 October, p 42). At the moment, we are hearing that elderly people in hospital in the UK are at risk of neglect as a result of indifferent nursing. If likely to die in the near future we may be put on the “Liverpool Care Pathway”. This involves heavy sedation and the withdrawal of food and fluids.
This is claimed to ease the passing of those deemed by hospital staff to be terminally ill, but is believed by some to intentionally speed “bed-blockers” on their way.
The most frequent response to sudden death in my age cohort is: “An awful shock for the family; but he/she was lucky.”
Dick Teresi’s article on diagnosing death (20 October, p 36) reminded me of the Bateson Life Revival Device, patented in 1852 and advertised as “a most economical, ingenious, and trustworthy mechanism… promoting peace of mind amongst the bereaved”. It consisted of an iron bell mounted on the gravestone with a wire down to the deceased’s hand.
There is no record of this device actually saving anyone’s life.
Binbrook, Ontario, Canada
Helping hands
For those of us who have never worked in a restaurant and do not have the skill of holding many plates at once, the extra robotic arms you report (27 October, p 18) could be useful when hosting a dinner party. More seriously, could they help elderly people perform tasks they struggle with, such as doing up and undoing buttons, putting on and taking off shoes or making cups of tea?
Monopoly genetics
Having read your editorial “Farms for the future” (13 October, p 5), I turned eagerly to Michael Marshall’s article putting forward the case for the defence for genetically modified food (p 8) to learn of the “host of benefits that have received little attention”. What I read was a familiar, and rather short, list of benefits promoted by the pro-GM lobby, now backed with some evidence. Marshall is right that “it can seem almost impossible to find reliable information on GM crops” in such a divided debate.
You do no one any favours by treating the issue as if it were purely one of science, thus missing the reason for the strong feelings on both sides. Science cannot be separated from the unequal balance of political and economic power which threatens to privatise agriculture itself.
Political evolution
A cry for academic freedom is often the last refuge of the intellectual charlatan. It appears that the article on political instincts by Jesse Graham and Sarah Estes (3 November, p 40) reports an example.
Born into a middle-class, Christian, Conservative family, I inherited my beliefs from the culture that surrounded me at home and school. Later, when I had experienced more and thought more, I flirted with atheist and left-wing views, before settling into a more conventional agnostic, Labour-voting clique. Now, married with a family, I find my beliefs do not map onto a left-right spectrum at all well.
If you really want to understand my political beliefs, you would be better served by interviewing me and observing my behaviour, than by considering how ordered my office is, or the structure of my brain.
The authors seem to hold that the brain is deterministic, but the mind is not. I suggest they do some work on the relationship between mind and brain.
If conservatives feel liberal research puts them in a bad light they should do their own to level the field. Oh, I forgot, they are against such research.
Berkeley, California, US
Young blood
Your article on transfusions of blood from young donors possibly reversing senility (20 October, p 10) sparked a long-forgotten memory of , an early 20th-century Russian experimentalist who made radical claims for the effects of transfusion. His claims have been viewed sceptically, but could be worth revisiting.
Out of cite
Samuel Arbesman (22 September, p 36) and subsequent letters such as Alan Bundy’s (20 October, p 31) seem to have missed a major reason for old, very important papers being cited less often as time goes on. The term in Scientometrics is “incorporation”, meaning that the result has become so integral a part of a discipline that no one feels the need to cite the original paper.
I have dubbed this the “second order Mössbauer effect”: nobody who now uses Mössbauer spectroscopy feels the need to cite original papers on his effect.
Wandering star
While reading the latest thinking on the past climate of Mars (20 October, p 44), I found myself wondering whether the planet has always been in its present orbit.
If it had a warmer, wetter climate 3.6 billion years ago, could it have been closer to the sun then? Could Mars have somehow been ejected into a new orbit at some point, causing it to lose its atmosphere and its water to freeze? Has anyone run simulations along these lines?
And if there is no life on Mars, will we still be determined to build a colony there?
Of lice and men
I enjoyed your article on the insight into human evolution provided by lice (3 November, p 36). However, the statement that similarities between genital lice and gorilla lice sparked speculation about the sexual proclivities of our ancestors led me to consider the possibility that the jump from gorilla to human could mark the point at which humans started drinking alcohol.
For the record
• We referred to “powdered nylon… called ABS” (6 October, p 22). Nylon and ABS are distinct groups of plastics.
• Oliver Sacks is no longer at Columbia University, but is currently a professor of neurology at the New York University School of Medicine (3 November, p 28).