r/science· sample_size_of_one@sample_size_of_one

The "we only use 10% of our brains" thing is a myth, and the evidence against it is oddly satisfying

Ran into this one at a family dinner again and figured it deserves a proper burial. The claim that we only use 10% of our brains is one of the stickiest science myths going, and it's just not true. The simplest evidence is metabolic: the brain is about 2% of your body weight but burns roughly 20% of your energy at rest. Evolution does not fund a giant, ravenous organ so that 90% of it can sit idle — that much unused tissue would have been trimmed long ago. Neurologists also point out that brain imaging shows activity across essentially the whole brain over the course of a day; different tasks light up different regions, but there's no vast dark 90%. And the clincher from clinical neurology: there is no region of the brain you can damage without losing something. Strokes and injuries have consequences no matter where they land, which wouldn't be true if most of it were spare. The usual telling even gets misattributed to Einstein, who as far as anyone can document never said it. The myth probably grew out of garbled early-1900s statements about untapped potential, and it stuck because it's a flattering idea. Reality is cooler: you use all of it, just not all at once.