We have all heard references to people being a "left-brained" or "right-brained" thinker. But researchers from the University of Utah say their latest research shows this is a myth.
Previous studies over the years have suggested that we use one half of our brain more often than the other, playing a part in the type of personality we have.
While the left side of the brain is usually associated with logical, analytical and detail-oriented behavior, the right side has been connected to creative, thoughtful and subjective thinking.
But a new study published in the journal PLOS ONE, suggests there is no evidence within brain imaging that proves some people are right-brained or left-brained.
The research team conducted a two-year study of 1,011 people who were part of the International Neuroimaging Data-Sharing Initiative (INDI), and who were between the ages of 7 and 29.
All participants had the functional lateralization of their brains measured. Functional lateralization means there are specific mental processes that take place in either the brain's left or right hemisphere.
Researchers have said the theory of "left-brained" or "right-brained" thinkers is nothing more than a myth
The scientists conducted the brain measurements using magnetic resonance imaging (MRI) analysis, which involved the participants lying in the scanner for 5 to 10 minutes while their "resting" brain measurements were taken. This allowed the researchers to correlate brain activity in one area of the brain and compare it with another.
The researchers then divided the brain into 7,000 regions and analyzed which regions of the brain showed more functional lateralization.
All connections in the brain were examined, and all possible combinations of the brain regions were correlated for each brain region that was left-lateralized or right-lateralized.
The results of the scan showed patterns indicating that a brain connection may be strongly left or right-lateralized. But they found no relationship that individuals "preferentially" used their left-brain network or right-brain more often.
Dr. Jeff Anderson, lead author of the study, explains:
"It is absolutely true that some brain functions occur in one or the other side of the brain. Language tends to be on the left, attention more on the right.
But people don't tend to have a stronger left- or right-sided brain network. It seems to be determined more, connection by connection."
Jared Nielsen, a graduate student in neuroscience at the University of Utah and one of the study authors, adds:
"If you have a connection that is strongly left-lateralized, it relates to other strongly lateralized connection only if both sets of connections have a brain region in common."
Results of this study are groundbreaking, Nielsen says, as they may change the way people think about the "right-brain versus left-brain theory."
"Everyone should understand the personality types associated with the terminology 'left-brained' and 'right-brained' and how they relate to him or her personally," he says.
"However, we just do not see patterns where the whole left-brain network is more connected or the whole right-brain network is more connected in some people. It may be that personality types have nothing to do with one hemisphere being more active, stronger, or more connected."