Newborn babies’ brains look remarkably similar to those of adultsCraig Boylan
We are born with the essential architecture of our brain raring to go. Over the previous nine months – give or take – some 100 billion neurons have sprung from a single 3 millimetre “neural tube” in the embryo that forms the blueprint for the entire central nervous system.
This sizeable number of neurons is dwarfed only by the 100 trillion or so connections that form between them, much like the lines between station hubs in a city’s metro system. “They’re forming in a smart way to make the system more efficient,” says developmental neuroscientist Moriah Thomasonat New York University.
Shortly before birth, the brain already looks remarkably like an adult brain: the connectome of the fetus shares 61 per cent of the same functional organisation as an adult brain. “That really is bananas,” says Thomason, but we shouldn’t mistake a fetus’s brain for a mini-adult brain. Some animals, like foals, are born with the ability to walk, feed and even gallop. But humans, with our exceptionally long childhoods, are highly social and dependent creatures.
“You want the brain to be unfinished because you want the environment into which you’re born to finish it off,” says philosopher of mind Timothy Bayne at Monash University in Australia. “It would be really bad for evolution to finish the brain such that you had to speak Swahili, and you’re born into a country which speaks Russian.”
