Neil deGrasse Tyson Challenges Popular Right-Brain / Left-Brain Myth

Neil deGrasse Tyson discusses the limitations of the right-brain / left-brain myth perpetuated by mainstream media and quizzes.

Neil deGrasse Tyson is a respected astrophysicist, cosmologist, author, and science communicator. When the American has thoughts on a subject, people tend to pay attention. And in 2015 he was interviewed by FastCompany about his TV show on National Geographic, Star Talk.

The Right Brain vs Left Brain Myth

During the interview, deGrasse debunked the myth of being left-brained vs right-brained. “Don’t call me left brained, right brained. Call me human,” Tyson said, voicing his opinion about using oversimplified labels in an effort to understand others.

“I’m disappointed with some aspects of civilization,” Tyson said. “One is our unending urge to bypass subtlety of character, thought, and expression and just categorize people … If you want to understand who and what a person is, have a conversation with him”.

“I’m ‘brained.’ Not right brained or left brained. I have a brain,” Tyson said.

This idea that people favour the use of one side of the brain is not even scientifically accurate. The myth is that those with a dominant left hemisphere are logical and therefore stronger when it comes to maths. Whereas those with a dominant right brain are more creative.

So where does the misconception originate from?

In a 2015 article in Los Angeles magazine, neuroscientist Michael Gazzaniga explained how previous research made it into the public consciousness – and was taken out of context. (Similarly to how the concept of using only 10% of the brain is used, when the original quote was that we only know what 10% of the brain is used for¹).

The Source of the Dominant Brain Myth 

In the 1960’s Gazzaniga worked with neurobiologist Roger Sperry, for his doctorate research. Sperry had discovered that cutting the connective corpus callosum fibers in monkey’s brains, effectively severing the two hemispheres, produced interesting results. The respective sides of the brain appeared to lose communication, suggesting that the fibres allowed them to talk to each other.

Gazzaniga found a similar, but less pronounced effect was produced when people suffering from epilepsy had their corpus callosum surgically severed to prevent seizures from spreading across the brain.

Gazzaniga worked with W.J., a World War II veteran with epilepsy who’d had the two hemisphere’s of his brain surgically disconnected². Gazzaniga presented an image of a square to W.J.’s left hemisphere (by limiting the image to his corresponding visual field). W.J. was able to identify a box.

However, when the image was presented to his right hemisphere, he was able to point at it, but he could not name the object in the image.

Gazzaniga proposed that while both hemisphere’s of the brain are able to visually process an image, only the left hemisphere can articulate what an image is. In the case of W.J., the severed communication between his two hemispheres meant required information was missing, and thus he was unable to name what he was seeing.

Gazzaniga’s research was important in demonstrating the need for communication between the two hemispheres in order for the brain to successfully carry out simple cognitive tasks. 

From the findings, the misconception arose in the 70’s of two distinct sets of traits being attributed to each respective hemisphere³; that concept has endured and continues to be perpetuated by online personality quizzes.

Sources

1. Neil deGrasse Tyson unpacks, debunks 11 sci-fi movie moments, syracuse.com.
2. Gazzaniga MS. The split-brain: rooting consciousness in biology. Proc Natl Acad Sci U S A. 2014 Dec 23;111(51):18093-4. doi: 10.1073/pnas.1417892111. PMID: 25538285; PMCID: PMC4280607.
3. Two astonishingly different persons inhabit our heads, The New York Times.