The 10% brain capacity myth

Anna Pitts addresses the pervasive cognitive conundrum head on

It is a well-known opinion that humans only have access to around 10 percent of their true brain capacity, according to the popular media and urban legend. This idea has had a resurgence of interest in the past few years with the popularity of films such as "Limitless" in 2011 and "Lucy" in 2014. "Limitless" is based on the premise that if science was advanced enough, there could be a nootropic (cognitive enhancing) pill that opens up your brain capacity over the normal level (in this case they cite 20%) for humans.

The film "Lucy" follows a similar story of a novel drug giving the protagonist psychokinetic powers; one of the main taglines of the film being: "If the average person uses 10% of their brain capacity. Imagine what she could do with 100%". The presumption widely being that if only humans could work out a way to access these apparently untapped areas of the brain, then we all would have vastly higher levels of intelligence and be able to reach our own unlimited potential. The exact origin of this concept is widely disputed and some people even wrongly credit Albert Einstein with the claim.

But what gives them such certainty in their disdain for this myth?

Firstly, technological advances such as PET (Positron Emission Tomography) scans and fMRI (Functional Magnetic Resonance Imaging) enable researchers to monitor brain activity in real-time in living subjects. These advanced imaging techniques have shown that, even when the person is sleeping, all areas of the brain are active to varying degrees. Also, neurologist Dr. Barry Gordon (of Johns Hopkins School of Medicine) has stated that: "We use virtually every part of the brain, and that (most of) the brain is active almost all the time". It is only in extreme examples of brain damage that researchers observe "silent areas" in the individual's brain.

Moreover, in cases of brain damage, if only 10% of the brain is normally used then injury to other regions of the brain would not have any impact on the individual's ability to function. However, research has shown this is not the case. Almost no area of the brain can be injured without in some way affecting the person's capabilities.

Scientists have spent years trying to successfully map the regions of the brain to discover if certain areas have specific purposes. To date, there has been no part of the brain that has been found to have no function. In fact, the brain is a very complex network with some regions appearing to be responsible for multiple functions and abilities. Therefore, although research into localization of function has come a long way in helping scientists understand which regions of the brain perform different tasks, it has also revealed the true complexity of the brain. This means scientists are still decades away from being close to fully comprehending how the brain works and how its structure relates to this. In more recent years it has been discovered that only 10% of the brain cells are neurons while 90% are glial cells. Glial cells are believed to surround neurons and aid them in their functions. But the exact capabilities of glial cells are still widely unknown.

There are nootropic drugs in the real world but these are highly controversial and the long-term effects are still not clearly defined. The most common form of nootropic drugs are stimulants such as caffeine. Attention has been drawn to these drugs recently due to an apparent trend of increased use in students to improve efficiency.

So, while films and books based around this myth are entertaining and intriguing, the premise remains fictional. It would be more accurate to state that, though it is a myth that humans only use 10% of our brains, currently researchers only fully comprehend around 10% of the brain’s capabilities.