Are you left or right-brained? This question actually asks: Are you the logical, analytical type or the creative, artistic sort? People who are more mathematically, linguistically, and methodically inclined are said to rely dominantly on their brain’s left hemisphere. On the other hand, those who are inclined toward creativity, art, intuition, and imagination are thought to be predominantly right-brainers.
Truth is, science is now partially debunking the left-vs-right-brain theory as myth. New research has scientists rethinking this contention which has been entrenched in modern psychology for the past several decades. There is no strict separation of functions anymore between the two hemispheres. Imagination isn’t solely the purview of the right hemisphere and neither is logic solely formulated by the left side. Scientists are now finding out that both hemispheres function cognitively in tandem.
The Left vs. Right Hemispheres Theory
The theory about the specified functions of the left and right hemispheres all started with psychobiologist Roger Sperry and his experiments on acute epileptic patients in the early 60s. The cure for severe epilepsy then was a surgical cut through the corpus callosum, the brain’s structure that connected the left and right hemispheres. A cut effectively separated the two hemispheres by severing the connection between them. As such, both hemispheres now operated independently of the other. With patients able to live with split brains, Sperry and his colleagues mapped out the functions of the two hemispheres in a series of experiments which earned Sperry the Nobel Prize in 1981.
The left hemisphere is believed to have dominant control over:
- Math skills
- Logic — sequential processing of information, analytical thinking
- Language — speech, reading, writing, spelling, memorization
- The right side of the body
The right hemisphere is responsible for following functions:
- Visual images
- Spatial abilities
- Facial recognition
- Perception of non-verbal information
- Understanding of metaphors
- The left side of the body
This theory was further expanded by psychology to encompass personality traits. Thus, artists are considered right brainers and lawyers, left brainers.
A lot of neuroscientists, however, had huge doubts over this theory. It seems both left and right hemispheres function in concert to do tasks thought to belong only to one specific side of the brain.
Confuting the Theory
Research on 1,000 brain scans at the University of Utah show no evidence of hemisphere preference when a subject person does specific tasks. In fact, the scans show the participation of the whole brain given a to-do or function.
Dr . Jeff Anderson, University of Utah’s director of fMRI Neurosurgical Mapping Service, says analytical thinking is not confined to just the left hemisphere of the brain nor does creative thinking appear to be solely performed by the right hemisphere. Creative and analytical thinking are not confined to activities by certain areas but are accomplished by connections among neurons in all brain regions. Thus, mathematicians don’t only solve mathematical equations using the left side of the brain. They do so with help from the right side and all other parts of the brain as well.
Anderson’s team studied brain activities of subjects aged 7-29 years old and at rest. General patterns showed both sides of the brain had essentially the same number of neural networks. Although some areas in the brain showed more activity than others, there was nothing to suggest in the 1,000 scans they studied that the left hemispheres had more neural connections than the right in analytically-minded people and vice-versa for the more creatively bent.
In addition, neuropsychologist Michael Saling from the University of Melbourne and Austin Health’s Epilepsy Centre says the concept of laterisation (the strict division of labour between the left and right hemispheres of the brain’s cerebral cortex) is too simplified. Although there is no doubt that the left hemisphere predominantly controls basic language processes, and navigation is handled by the right, the level of ability for these cognitive skills are actually determined by both hemispheres working in tandem with each other. This means every cognitive task such as verbalization, painting, music appreciation, and logic formulation has both left and right sides working together. Each hemisphere has its own input and function, a sort of cortical division of labour that avoids competition between the two halves.
The journal, “Social Cognitive and Affective Neuroscience,” revealed a study from the University of Southern California which demonstrated the left hemisphere as a vital support of the right in creative tasks. The study involved architectural students, known to be visually creative and therefore right-brainers, undergoing functional magnetic resonance imaging (fMRI) while looking at 3 shapes: circle, C, and 8. They had to creatively think what new images they could come up with using these 3 images. Contrary to the lateralisation concept, the participants’ left hemispheres showed more brain activity than the expected right side during the creativity test. This showed that the left hemisphere was working hard to support the right hemisphere’s creative function.
So, Are You Left-Brained or Right-Brained?
The answer then is neither. You are “whole-brained.” You create, solve problems, write, and imagine with a unified cerebral cortex at work. No one hemisphere gets full control of what you do.
The brain is indeed a mystery. Until we unlock the mind, one of science’s frontiers, man as a whole remains a mystery, as well.