Do we only use 10 percent of our Brains?

of our brain

With the movie Lucy hitting the theaters some of your friends might try and convince you that you only use a small fraction of your brain and that you in reality could have latent super powers just a miracle drug away. This is of course not the case but the result of a really persistent myth that dates back more than a hundred years.

Only 10 Percent of our Brains

It is unsure exactly were this myth begun. Some put the origins at the hand of Harvard psychologists William James and Boris Sidis. Where they in raising a child progeny presented the case in front of audiences as: humans only meet a fraction of their full mental potential. This was later given a specific number (10%) in the foreword to the book “How to win friends and influence people” by the writer Lowell Thomas.

Some attribute the myth to the neurosurgeon Karl Lashley that performed experiments on rats in the early 1900’s. He removed parts of the rats brain and had them run a maze. When bigger parts of the brains were removed it naturally became more difficult for the mice to run the mazes, but he discovered it could be fixed with additional training. Which lead him to postulate that different areas of the brain can take over and perform the same functions as others.

Wherever its origins the idea itself is often used in books and movies however ludicrous it might be. Gunshot wounds and stroke victims in themselves provide enough evidence that damage even to small regions of the brain can be fatal or severely debilitating.

The evolutionary perspective also takes a large chunk out of the myth. The brain uses a lot of energy, it makes up about 2% of our body mass but actually uses a whopping 20% of our energy needs. It is not especially efficient to use more energy than you really need from an evolutionary perspective and if it was true it would have been a big disadvantage and selected against.

The whole idea of the myth probably stems from how little we know about the brain as a whole. This lack of knowledge is easier to attribute to some kind of latent super powers, especially 80 years ago, than the “mundane” reality of the knowledge we are missing.

Cover and content image own creation based on public domain image of the brain from wikimedia