It’s thought that most of us use just 10% of our brain. Is there any truth to this claim, or is it just another accepted myth?
Many organs indeed have more capacity than we need daily. For instance, you can get along fine without an entire lung or kidney, or even your appendix, thymus, and spleen. But that’s not true of the brain. Brain scans like magnetic resonance imaging (MRI) and positron emission tomography (PET) show that people regularly use all of the brain. Some parts may be more active at any given time or during a particular activity. But there is no part of the brain that is known to be unused or completely unnecessary.
Where did the 10% claim originate? You could point to the brain’s mysterious ways.
For the longest time, scientists had no reliable way to measure the brain in action. Even now, MRI and PET scans don’t provide a perfect estimate of how much we use our brain at any one time. Plus, when a brain area is engaged during an activity, not every cell in that part is used at that exact moment. But that does not mean those cells are never used.
Here is another way to think about it: If we had that much unused brain capacity, we should withstand most brain diseases or damage. But we don’t. That 10% claim? Consider it 100% fiction.
Image: © MaksimYremenko/Getty Images
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