🧠 Is it true that we only use 10 percent of our brain?

The idea that humans only use 10 percent of their brain is very widespread. It appears regularly in self-help books, movies, or popular discussions. This claim suggests that a vast reserve of brain capacity remains unused.

Neuroscientists today consider it a neuromyth, as explained by the MIT McGovern Institute for Brain Research.


The human brain is an extremely active organ. Even at rest, many brain regions function simultaneously to maintain vital functions, process sensory information, and regulate body activity. Modern brain imaging techniques, such as functional MRI or positron emission tomography, allow the observation of brain activity in real time. These brain imaging observations show that different areas activate according to the task being performed, contradicting the idea that a large part of the brain remains inactive.

Neuroscience indicates that almost all areas of the brain serve a precise function. Some regions are involved in vision, others in language, memory, or movement control. Even when performing a simple task, several neural networks cooperate. Areas that seem less active in a given situation may intervene in other situations.

Another argument comes from brain injuries. If 90 percent of the brain were useless, a large portion of neurological damage should have little effect on behavior. However, medicine shows the opposite. Even small lesions in certain brain regions can cause significant disorders, such as difficulties speaking, moving, or recognizing objects.

The brain's energy consumption also constitutes an important clue. This organ represents about 2 percent of body weight, but it consumes nearly 20 percent of the energy used by the body at rest. Such an expenditure would be difficult to explain if the majority of the brain remained inactive.

The origin of the 10 percent myth is not clearly established. It may stem from a misinterpretation of old psychological work or from excessive simplifications in early neuron studies. Some quotes attributed to scientists or public figures have also contributed to popularizing this idea, without a solid experimental basis.

Neuroscience research today shows that the entire brain is used. Not all regions operate at maximum capacity all the time, but they participate in different networks depending on activities and situations. Rather than a largely unused organ, the brain appears as a dynamic system in which billions of neurons constantly cooperate to produce thought, emotions, and actions.