Why on Earth? Brains.
Is it true that we use only 10% of our brains?
Of all popular notions about brain power, the idea that we get through life exploiting only a tiny fraction of our true potential has got to be the most popular. It’s been peddled by self-improvement gurus who want to persuade us we have untapped potential, and by psychics who attribute their weird mental powers to finding a way of tapping the unused 90 percent. It is, however, totally untrue.
According to Sergio della Sala, professor of neuropsychology at the University of Aberdeen, there are many clues suggesting the ‘10%’ idea is a myth. Strokes, for example, would be expected to incapacitate only one in 10 of the people who suffer them, and scans which measure brain functions should reveal huge areas where there is no electrical activity at all. In fact, strokes can be devastating wherever they occur, and while some areas of the brain are busier than others, there is no evidence any of our grey matter is lying fallow.
The laws of natural selection also suggest man is unlikely to have evolved such a wasteful excess of mental capacity. The brain is a very ‘expensive’ organ to run - although it accounts for only 2 percent of body weight, it consumes 20% of the body’s oxygen supply and holds 20% of nutrient-bearing blood. Diverting all of that energy to maintaining useless excess capacity makes no sense in evolutionary terms.
The idea that nine-tenths of our brain remains unused seems to have established itself decades before modern technology made these discoveries possible, but even psychologist Barry Beyerstein of the University of Calgary - who has made a lengthy study myth - is uncertain exactly where it first took root. It certainly goes back to the early years of this century, when it was vigorously promoted by the self-help movement that produced such luminaries as Dale Carnegie and his How to Win Friends and Influence People. But one thing Beyerstein is sure of is the reason why the 10% myth has such a firm hold. ‘It conveys the welcome message that we could all be Einsteins, Rockefellers or Uri Gellers,’ he explains, ‘if we could just engage that ballast between our ears.’