The side of your brain that is more active, right or left, determines your personality traits and career path, which can supposedly be identified by a simple thumb test –  if your right thumb is on top when you join hands, you’re left-brained (logical), and if your left thumb is on top, you’re right-brained (creative).

FACT: 

Experts suggest that a simple thumb test cannot determine which side of the brain is dominant. Brain hemispheres work together on all complex tasks, and career choices are influenced by multiple factors, not just one side of the brain.

You’ve probably come across quizzes or viral reels claiming you are either “right-brained” or “left-brained” and that this determines whether you’re creative, logical, or even suited for a particular career. But is there any truth to this idea?

That’s the question raised by Rajneesh Upreti, founder of BimaSchool, whose recent Instagram reel has gone viral.

Upreti suggests that knowing which side of your brain is more active can help determine your career choices. In the reel, he demonstrates a simple exercise: putting your hands together and observing which thumb rests on top.

He says, “If your right thumb is up, then your left brain is more active, which means you are more logical. And if your left thumb is up, then your right brain is more active, which means you are more intuitive and emotions drive you.” He further explains that “left brain means numbers, logic and maths, and right brain means imagination, music, intuition and creativity.”

Is there any scientific basis behind the claim that your dominant brain side dictates your career path?

Dr Viswanathan Iyer, Neurosurgeon at Zynova Shalby Hospital, Mumbai, clears the air.

Does the more active side of your brain (right or left) really decide your career path?

“Such a simple test cannot determine which side of the brain is dominant. There are complex psychometric tests and questionnaires to determine this,” says Dr Iyer.

He said that later research has shown the brain is not nearly as dichotomous as once thought, and that abilities in subjects such as math are strongest when both halves of the brain work together.

Dr Iyer said that today, neuroscientists know the two sides of the brain collaborate to perform a broad variety of tasks and communicate constantly through the corpus callosum. He added, “No matter how lateralised the brain can get, though, the two sides still work together.”

He also noted that some brain functions tend to occur more in one hemisphere than the other. He said that “language tends to be on the left, attention more on the right,” but added that “people don’t tend to have a stronger left- or right-sided brain network.”

“The concept that career paths are determined by being ‘left-brained’ (logical) or ‘right-brained’ (creative) is a persistent myth and a vast oversimplification of brain lateralisation,” he added.

“While the brain’s hemispheres do have specialised functions, they are in constant communication and work together on all complex tasks. A person’s cognitive strengths, which are influenced by genetics and environment, can correlate with certain career aptitudes, but neither hemisphere works in isolation,” he added.