The idea that people are either left-brained or right-brained has been a popular topic for decades. It’s often said that left-brained individuals are logical and analytical, while right-brained people are creative and emotional. But how much of this is based on scientific evidence, and how much is just pop psychology?
What does the left brain and right brain theory suggest?
The left brain vs. right brain theory posits that each hemisphere of the brain controls different types of cognitive skills. According to this theory, the left hemisphere is responsible for logical reasoning, analytical skills, and language. On the other hand, the right hemisphere is said to control creativity, intuition, and emotional intelligence.
Where did this theory originate?
The concept of lateralisation of brain function, or the idea that different parts of the brain control different functions, has been around for centuries. But the modern version of the left brain vs right brain theory gained traction in the 1960s, following research on split-brain patients – people who had the corpus callosum, the bundle of nerves connecting the two hemispheres, severed to treat severe epilepsy.
What does the science say?
While it’s true that certain functions are lateralised in the brain, the idea of a dominant hemisphere is largely debunked. A comprehensive study published in the journal PLOS One analysed brain scans of over 1,000 individuals and found no evidence supporting the idea of hemispheric dominance. The researchers concluded that individuals use both hemispheres equally for all types of cognitive functions (Nielsen, Zielinski, Ferguson, Lainhart, & Anderson, 2013).
Another study published in Frontiers in Human Neuroscience emphasises that cognitive functions are not isolated to one hemisphere but are a result of networked regions across the entire brain.
Why does the myth persist?
Despite the lack of scientific evidence, the idea of left brain vs. right brain dominance continues to be popular. One reason could be its simplicity; it’s easier to categorise people into two distinct groups. Moreover, the theory has been widely marketed in self-help books and online quizzes, which adds to its allure.
Implications for education and career
The persistence of this myth has real-world consequences, especially in education and career choices. Labelling students as left-brained or right-brained can limit their potential by creating a fixed mindset. Educators and employers should focus on a more holistic approach to cognitive skills, recognising that abilities are not confined to one hemisphere of the brain.
While the concept of left brain vs. right brain dominance is intriguing, it’s essential to approach it with a critical mind. The scientific evidence overwhelmingly suggests that cognitive functions are not isolated to one hemisphere but are a collaborative effort of the entire brain. So, the next time someone tries to label you as a left-brained or right-brained individual, remember that your abilities are far more complex and cannot be boxed into such simplistic categories.
Roger O’Sullivan, PhD is a cognitive neuroscientist specialising in brain lateralisation research.