There are two other phenomena that might account for the misunderstanding. Nine-tenths of the cells in the brain are so-called glial cells. These are the support cells, the white matter, which provide physical and nutritional help for the other 10% of cells, the neurons, which make up the grey matter than does the thinking. So perhaps people heard that only 10% of the cells do the hard graft and assumed that we could harness the glial cells too. But these are different kind of cells entirely. There is no way that they could suddenly transform themselves into neurons, giving us extra brain power.
There is a very rare group of patients whose brain scans reveal something extraordinary, though. In 1980, a British paediatrician called John Lorber mentioned in the journal Science that he had patients with hydrocephalus who had hardly any brain tissue, yet could function. This doesn’t of course show us that the rest of us could make extra use of our brains, just that these people have adapted to extraordinary circumstances.
It is, of course, true that if we put our minds to it we can learn new things, and there is increasing evidence in the area of neuroplasticity showing that this changes our brains. But we are not tapping into a new area of the brain. We create new connections between nerve cells or lose old connections that we no longer need.
What I find most intriguing about this myth is how disappointed people are when you tell them it’s not true. Maybe it’s the figure of 10% that is so appealing because it is so low that it offers massive potential for improvement. We’d all like to be better. And we can be better if we try. But, sadly, finding an unused portion of our brains isn’t the way it’s going to happen.
You can hear more Medical Myths on Health Check on the BBC World Service.
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