The idea that we only use a small part of our brain is a myth
If you’ve ever heard that humans only use ten percent of their brain while the remaining ninety lies dormant, know that this is one of the most persistent scientific myths in history. It’s repeated in movies, self-help books, and even in school classrooms. But neuroscience has long proven that the brain works as a whole, and no part of it sits idle. And now we’ll see why.
Where the 10 Percent Brain Myth Came From
The history of this misconception goes back to the late 19th century. The likely source is considered to be the ideas of Harvard psychologists William James and Boris Sidis about “reserve energy,” which they developed in the 1890s. James wrote and spoke about how the average person realizes only a small fraction of their potential. However, he never mentioned specific percentages and always meant untapped capabilities, not gray matter.
So how did the specific figure of 10% appear? According to TASS, in 1936, American journalist and writer Lowell Thomas, in the foreword to Dale Carnegie’s book “How to Win Friends and Influence People,” attributed to James a phrase stating that the average person develops only ten percent of their latent mental abilities. Thus, a cautious philosophical observation about untapped potential gradually transformed into “ten percent of the brain.” Carnegie’s book became a bestseller, and the myth spread around the world.
Why the Brain Myth Is Associated with Einstein
Over time, the myth acquired additional “confirmations.” One of the most famous is a false quote attributed to Albert Einstein, who supposedly explained his genius by claiming he used more than ten percent of his brain. However, no documentary evidence of such a statement exists, and this too is a myth.
Another possible reason is the work of neurosurgeon Wilder Penfield. In the 1930s, he stimulated areas of the brain with electricity during operations on patients with epilepsy. Some areas of the cerebral cortex showed no visible reaction, and early researchers called them the “silent cortex.” Scientists never claimed these zones were useless, but that was the impression left on the general public. Today it is known that these areas perform complex functions, from speech processing to abstract thinking.
Why Even Teachers Believe the Brain Myth
You might think that in the 21st century, such things have long been debunked. But no. According to research, about 50% of school teachers in various countries around the world believe that we truly use only ten percent of our brain. A survey conducted in Brazil among people with higher education showed that 59% believe in this myth.
Why is the myth so persistent? It’s appealing on an intuitive level: everyone wants to believe there’s a huge untapped reserve inside. Additionally, the idea is actively fueled by movies like “Lucy” (2014) and “Limitless” (2011), where characters “unlock” the brain’s hidden potential with stunning results.
How the Brain Actually Works: MRI Data
Modern technologies like MRI allow us to literally observe the brain in real time. Scanning shows that all areas of the brain are always active, although some regions work more intensely than others at any given moment. But there is no zone that is completely “switched off.”
The brain consumes a disproportionately large amount of energy for its size. Weighing about 2% of total body mass, it uses approximately 20% of all the oxygen and calories consumed by the body. And this high metabolic rate remains remarkably stable regardless of whether you’re solving a complex problem or simply lying on the couch. From an evolutionary standpoint, such expenditure would be absurd if 90% of the organ were idle.
Even during sleep, the brain doesn’t rest. In a resting state, the so-called default mode network operates — an extensive system of brain regions that is active and synchronized even when a person is not performing any tasks.
Modern tomography shows that the brain is fully active, even when we’re resting
Why Pushing the Brain to 100% Is Dangerous
If all parts of the brain are already working, what would happen if they all “switched to full power” at once? Using the entire brain simultaneously without coordination is undesirable — such uncontrolled activity would almost certainly cause an epileptic seizure.
Epilepsy is precisely the result of abnormal, excessive neuron activity. When too many brain cells “fire” simultaneously and chaotically, it causes convulsions and loss of consciousness. A healthy brain doesn’t work at maximum capacity but in a coordinated manner: some zones activate while others slow down at the same time. This isn’t a bug — it’s a key feature of normal functioning.
Attempts to “speed up” the brain with dubious supplements or methods can cause harm. There are no “tricks” for dramatically increasing brain power: the brain works best with proper sleep, physical activity, low stress, and balanced nutrition.
What the Brain’s True Untapped Potential Really Is
It’s important to understand the difference between the myth and the real kernel of truth hidden within it. William James never claimed that we use only a small fraction of our brain. He spoke about how people don’t always feel fully energetic and engaged — and this was an observation about everyday habits and motivation, not about physiology.
The only limitation to acquiring new skills appears to be the time we invest in practice. So while we have no untouched gray matter, the unrealized potential for most people is indeed enormous. In other words, the entire brain is already engaged, but that doesn’t mean we’re using its capabilities in the best possible way. Learning, training, getting enough sleep — these are the real ways to become smarter, without magic pills.
The ten percent myth persists not because people are foolish, but because it contains an appealing idea — each of us has hidden reserves. This idea is true, but not in the sense commonly attributed to it. The brain is indeed capable of more through learning, new experiences, and rewiring neural connections. It’s just that you don’t need to activate some dormant zone for this: you need to skillfully use what’s already working.
