If you were born with half a brain, would you even notice?

We’ve long known that the size of the brain appears to matter less than you may assume. This is true across the animal kingdom and in our own evolutionary history. Neanderthals were better endowed up there than us modern humans, yet it was our species that emerged to build civilisation.

As our columnist Tom Stafford explained in 2014, one girl was born without a key part of the brain – the cerebellum towards the base of the skull – that normally contains half our neurons, yet she appeared to have lived a relatively normal life; graduating from school, getting married and having a baby. Although her movements were always a bit clumsy, the effects were relatively minor given just how much of her brain was missing.

Thanks to many other medical case studies, we now know that the brain is capable of astonishing recovery after substantial damage – even if the personality is permanently altered. Watch the video below to learn more about one particularly astonishing story of injury and recovery

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