Adam Zeman
Only Connect
Connectome: How the Brain’s Wiring Makes Us Who We Are
By Sebastian Seung
Allen Lane/The Penguin Press 359pp £20 order from our bookshop
Forest, jungle, labyrinth, maze – the human brain attracts dizzying analogies, and with good reason: our brains contain around one hundred thousand million nerve cells (neurons), linked by ‘millions of miles of gossamer neurites’ permitting around one thousand million million interconnections (synapses), the points at which cells exchange information with one another. It has long been thought that these interconnections provide a key to human nature: while the broad pattern of connections between brain regions is similar in every healthy human brain, their details – their number, size and strength – are thought to underpin our individuality, as synapses are ‘plastic’, shaped by experience. This shaping process obeys the ‘Hebbian rule’, named after the influential Canadian psychologist Donald Hebb, which dictates that ‘cells that fire together wire together’. It is the consistent coactivation of brain cells representing your kitchen or your beloved, for example, and the resulting synaptic changes in your brain, that allow you to summon them up in your mind’s eye without, I would imagine, too much trouble. The sum total of the connections within your brain, your ‘wiring diagram’, constitutes your ‘connectome’. In Sebastian Seung’s view, argued provocatively here, ‘you are your connectome’.
His book is an engaging introduction to the study of the human wiring diagram. This project has been given fresh impetus by some recent techniques facilitating the tracing of neuronal interconnections. These range from methods working at very fine scales, examining individual synapses in slices of brain under huge magnifications,
Sign Up to our newsletter
Receive free articles, highlights from the archive, news, details of prizes, and much more.@Lit_Review
Follow Literary Review on Twitter
'As it starts to infect your dreams, you realise that "Portal 2" is really an allegory of the imaginative leap: the way in which we traverse the space between distant concepts, via the secret conduits we place within them.'
https://literaryreview.co.uk/portal-agony
'Any story about Eden has to be a story about the Fall; unchanging serenity does not make a narrative.'
@suzifeay reviews Jim Crace's 'eden'.
https://literaryreview.co.uk/trouble-in-paradise
The first holiday camps had an 'ethos of muscular health as a marker of social respectability, and were alcohol-free. How different from our modern Costa Brava – not to mention the innumerable other coasts around the world now changed forever'.
https://literaryreview.co.uk/from-mont-blanc-to-magaluf