There are some urban legends, myths, memes, lies or whatever you want to call it … that are so much given for granted by certain people that it really amazes me. One of them is the so called 10% of the brain myth:
On average humans only use 10% of their brain.
Another version of this myth states that Einstein used more than 10% and that is why he was so clever and made all the discoveries he made. Even more, this false myth is in some cases attributed to Einstein! Also you probably have heard that you could increase your intelligence by using more than 10% of your brain. All of this belongs to the same myth.
Mouth-to-mouth, repeating things you hear without thinking (which I call the “parrot effect”) and movies such as “Lucy” helps to keep this myth alive. Actually, I liked the movie “Lucy”. The photography is great, the juxtaposition of wild animals with some scenes is original, and the tempo and the script of the movie are good. But I am quite disappointed because this movie will keep spreading this false myth. Actually all the movie develops around the 10% of the brain myth. Even in the movie poster this can be read! This will only generate more people accepting this false believe. Well, next time I have to explain this all over again, I will point people to this post. If you still believe in the 10% of the brain myth, please keep reading.
From an evolutionary point of view, it would be completely non-sense that our brain is not optimal. Do we have parts of our body that are useless? Well, besides the wisdom teeth and the appendix which are evolutionary vestiges of the past, our body is quite perfect and efficient. Taking into account that the human brain is one of the most complex things known to man (according to the human brain), it is hard to believe that 90% of it is unused.
If you have a look to this previous post “The brain in numbers”, you will be amazed to see how complex the brain is, and you will also learn that it consume about 20% of your total energy. If our brain was using its full capacity, just by making some numbers, we will see that the brain would be consuming 200% of our total energy. Non-sense again.
Brian Injuries argument
Another bold argument is that if 90% of our brain is unused, then brain injuries in those areas would not have any type of effect, although brain damage, no matter how small, virtually always affects performance and/or cognition. Maybe next time some one tells us about this myth we should challenge him/her to give us a small part of his brain. Broadly 9 out of 10 times, no effect would occur, right?
Brain Imagery argument
Finally, one last argument is that all the brain imaging techniques (EEG, fMRI, PET) shows us that (all) the brain is always active, even when we sleep. Some parts of the brain would be more active if we perform some different tasks, but even in relax/sleep mode, the full brain is active. We only see non-active areas of the brain in case of serious brain damage.