Lucy Movie with Scarlett Johansson Based on Ridiculous 10% of Brain Myth: We Only Use Part Our Brains

Posted on 16 May 2014 14:14

It's a long debunked myth but it is still one of most popular questions posed to neuroscientists and psychologists: "Is it true was only use 10% of our brains?" The new Summer movie "Lucy" starring Scarlett Johansson and Luc Besson asks us to "Imagine if you were able to unlock 100% of your brain power." This is another example of Hollywood's tradition of science fiction based on fantasy.

Why? Because, if you actually pose the question about using 10 percent of your brain to a neuroscientist, the answer, according to authors of 50 Great Myths of Popular Psychology: Shattering Widespread Misconceptions is, "Sorry, I'm afraid not."

It's disappointing, no? Wouldn't it be nice if it were true and some breakthrough, like a pill or something, could turn us into big-brained superhumans with unlimited cognitive powers, including a little telekinesis and maybe a little clairvoyance to boot?

There are tons of charlatans who would like you to believe just that, and that they can tell you how to unlock the 90% of your brain you, as of now, have no access to. The myth survives even among many psychology students! But it is an absurd proposition. Let's look at why:

1. Brain tissue takes a lot of resources to grow and maintain. In fact, even though it only comprises 2 or 3% of our body-weight, it takes up over 20% of the oxygen we breathe. Growing a huge brain, which must be constantly maintained and supplied with energy, only to let 90% of it sit around doing absolutely nothing would be an evolutionary wonder. Natural selection does not favor expensive resources that have no purpose!


50 Great Myths of Popular Psychology
not only discusses the 10% brain myth,
but right brained v. left brain, ESP,
subliminal messaging, "Baby Mozart",
the midlife crisis, hypnosis, IQ tests
are biased, and so much more!

2. Losing even a fraction of 90% of the brain in an accident or other circumstance has devastating consequence. If you weren't actually using it, losing it wouldn't matter. Scott O. Lilienfield and the other authors of 50 Great Myths of Popular Psychology bring up the controversy surrounding Terri Schiavo, the young woman from Florida who was in a persistent vegetative state for 15 years following a cardiac arrest in 1990 that destroyed about 50% of her cerebrum, the upper part of the brain responsible for awareness. Although many people thought they saw hopeful signs of awareness, most experts found no evidence that she retained any capacity for thoughts, perceptions, memories, or emotions. If 90% of the brain is left unused and unnecessary, this should not have happened. In fact, there does not seem to be any area of the brain that can be destroyed without the patient having serious functional deficits.

3. Electrical stimulation of different parts of the brain during neurosurgery has failed to find any silent areas. Every part of the brain, if stimulated by an electrical current, makes something happen in the patient, such as a perceptions, or emotions, or movement. Basically, all the parts of the brain, 100% of it, do something!

4. Brain imaging technologies, which are becoming more and more sophisticated, also fail to find any silent areas of the brain.

5. When an area of the brain goes unused because of injury or disease, it simply degenerates. If you have unused tissue in your brain, it will basically whither away. Either that or they are co-opted by another area of the brain that is in need of new resources. In other words, perfectly good brain tissue would never just sit there taking up resources. The tissues would either degenerate or the brain would start using them for some other purpose than they originally were used for.

Lucy Official Movie Trailer

Given that it seems to be such a silly proposition, how did this myth get started? There is no evidence of a scientist saying, long ago, "We only use 10% of our brains." There is no "smoking gun" as the authors put it, but one possible link is the 19th and 20th century American psychologist William James, who wrote that he doubted the average human achieves more than 10% of their intellectual potential. Hopefully, you can see that this is a far cry from saying the average human only uses 10% of their brain matter. But enter the "positive thinking" movement and self-help gurus eventually turned "10% of our intellectual capacity" into "10% of our brain." At least, this is a likely origin of the myth. It is true that in the preface to Dale Carnegie's How to Win Friends and Influence People, Lowell Thomas attributed the 10% brain statement to William James, and this may well be where the myth really took off. For more on this and other huge myths of psychology, see the book.

Lucy may well be an action-packed and entertaining movie. But for science fiction, it leaves a lot to be desired in the science department. I am the first to say that movies are just movies, and you don't always have to take them too seriously. But the key to good science fiction is that, even when the science is stretched, you are able to suspend disbelief. When the scientific premise of a work is based on complete and utter crap, I, personally, have a hard time doing that. No matter how hard I try to sit back and just enjoy some mindless entertainment, the absurdity keeps pulling me back to reality and makes me say "This is friggin stupid."

If you watch this movie, whatever you do, don't watch it to learn about the brain!

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This page created 16 May 2014 14:14
Last updated 06 Aug 2016 19:23

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