LIMITLESS and the Myth of “Only Ten Percent” Brain Usage

The new sci-fi movie Limitless is out, about a new drug that allows a writer to access his entire brain, turning him into a super-intelligent business tycoon. Personally, I thought it was a little too familiar, sort of a Flowers for Algernon tale with the twist of making the hero unpleasant. However, what I found more interesting is that the entire movie is based on one of the most popular and unscientific myths out there: that we only use ten percent of our brains. That’s one hundred percent wrong.

You’ve heard it a million times. “We only use ten percent of our brains! Think what we could do if we could access the rest of it!” Actually, Limitless changes the percentage to twenty percent, but the idea is the same. Limitless isn’t the first movie to play with the myth. Defending Your Life, Scott Pilgrim vs. The World, and The Sorcerer’s Apprentice are also movies that exploit the concept. In the real world, the ten-percent myth is usually quoted by people like Uri Geller and Craig Karges to promote the concept of psychic powers.

The myth is believed to be a classic case of an overzealous media promoting information that wasn’t fully understood. By the early thirties, scientists had a very limited understanding about how the brain worked. As a result, neuroscience couldn’t figure out what over ninety percent of the brain was for. Somehow, that statement got translated as “we don’t use ninety percent of the brain.” This, coupled with the discovery that people could survive massive head trauma, including the removal of fully half of the brain, led to the idea that we just carry around a mostly useless lump of tissue in our heads.

We now know that the exact opposite is true. New technology like PET scans have shown that humans actually use all of our brains, just not all the time. The best analogy is that our brains are like houses – not all the rooms are used at all times, but that doesn’t mean that those rooms are useless. We’ve also come to understand that survivors of brain trauma are a testament to the ability to shift responsibilities to other parts of the brain. But I guess the idea that we all have a greater potential waiting to be unlocked is too appealing a concept to ignore.