5 Brain Myths That Won't Go Away


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Psychologist Gary Marcus recently pointed out that scientists are not only far from a comprehensive explanation of how the brain works, they can’t even agree on the best way to study it. So it’s not surprising that myths and misinformation continue to persist —spurred on, in part, by pop culture. But why do we continue to buy into these falsehoods?

"The reason that these myths persist is because they resonate with people," Amy Shelton, PhD, director of research at Johns Hopkins University’s Center for Talented Youth, told Yahoo Health. It’s true several of these myths, said Shelton, are simplified versions of complex concepts that we can often relate to on a personal level. Here are five popular myths that just won’t go away.

Myth: You only use 10 percent of your brain.

If we now only use 10 percent of our brains, imagine the limitless possibilities for the human race. Well, Hollywood did just that, and we get Lucy, the superhuman, butt-kicking heroine played by Scarlett Johansson, who mastered 100 percent of her brain. Unfortunately, the entire movie is based on one of the oldest brain myths out there.

Shelton, who teaches a class on brain myths and fold psychology, says this myth’s origins are all over the map. What’s not surprising, though, is why it’s still around. “We see it as unleashed potential,” she said. “The idea that we don’t use all of our brain fits well with the idea that we could be better and do more, and that’s encouraging.”

She added that psychologists do believe that you can make your brain more efficient and improve different cognitive skills, but it’s simply untrue that a huge portion of your brain is sitting there in the off position. “Any part of your brain that isn’t used will whither and die,” she said.

Myth: You are either right- or left-brained dominant.

This idea is responsible for dividing the entire human race into either creative (right-brained) or logical (left-brained) people. The myth is rooted in proven science (that certain areas and sides of our brains control specific functions) that was hijacked by pop-psychology and twisted into the notion that our personalities are determined by how much we use one side or the other.

"In reality, we are all whole-brain users." said Shelton. "But this myth helps people define their differences, similar to calling someone male or female. So if you define yourself as right-brained, it immediately connects you with a set of predetermined qualities."

The brain is indeed divided into two parts, each responsible for various tasks and processes. For example, the left hemisphere is responsible for language production in most of us and handles counting and memory recall. The right hemisphere deals with spatial reasoning and estimation. However, to manage the both mundane and more complex tasks of daily life, a mountain of research and thousands of brain scans have proven that we use both sides of our brain equally.

Myth: Alcohol kills brain cells.

This one actually makes sense. It seems plausible one-too-many adult beverages (which often leads to ridiculous behavior) could lead to a depleted source of brain cells. But the research of biochemist Roberta Pentney debunked this myth years ago.

To be clear, pure ethyl alcohol is used as a disinfectant and will kill brain cells on contact. However, when it is diluted and delivered into the body via an alcoholic drink like beer or wine, its lethality diminishes and our bodies are able to process it before it goes postal on our cells. And though it doesn’t destroy neurons, it certainly damages their ability to communicate, which causes the buzzed feeling you feel after a couple of drinks. The good news is the effect is temporary, and the damage is not permanent.

Myth: Brain damage is permanent.

When brain cells are actually destroyed, the result is what we often refer to as “brain damage.” And neuroscientists used to believe it was irreversible. “A couple of decades ago, you could pull any textbook, and it would tell you that you had your full complement of neurons at birth and they couldn’t be replaced,” said  Shelton. “Now we know that’s just plain wrong. As imaging technology became more sophisticated, researchers discovered that the brain can regenerate cells, a process call “neurogenesis,” and even reroute connections around damaged neurons.

Not all brain damage can be repaired; it really depends on the location of the injury and how severe it is. The prognosis after a brain injury is hard to predict, but doctors now know that brain damage does not automatically mean permanent disability.

Myth: Your IQ is a fixed number.

Your IQ (intelligence quotient) is a score designed to quantify how smart you are. What makes a person smart is casually debatable, but scientists have worked long and hard to develop an objective test that measures intelligence.

People still believe that our individual IQs are fixed at birth and don’t change throughout our lives – that our smarts are genetically predisposed. While scientists do believe that genetics (as well as environmental factors) help determine our IQ, they also now know that the number can be changed.

"There is a lot of cognitive training that can be done to improve things that are used to test IQ, such as critical thinking skills and the ability to process logic," Shelton said. "So if we know we can make someone better at those skills, then that would suggest that IQ should be at least somewhat malleable."