Table of Contents
Supporting evidence and origin of the myth
The Myth Busting Evidence
Sources
People are often taught that they can be either left-brained, or right-brained. Google has over 200 million results. Oprah is a “right brained” person. But there are no left-brain dominant or right-brain. The corpus callosum connects the two halves of the human brain. The task will determine which hemispheres are activated more often than others. Each hemisphere is assigned a task that controls movement and receives stimuli from the other side. Also, the left side of the brain controls movement and receives stimuli from the right. Our brains are highly interactive and have a complex exchange.
In a 2016 study, 78.5% accepted that hemispheric supremacy was valid even though other studies have shown cerebral functions require use of both the hemispheres. However, there is no evidence linking learning and hemispheric supremacy (Dundar-Gunduz, 2016). Brain-based learning also has an impact on the development of curriculum (Society for Neurosciences, 2009). Therefore, teachers might unknowingly include other neuromyths into their pedagogy. In many cases, neuroscientific expertise is lacking in educational institutions. This can lead to “brain-based” learning methods being adopted. But they don’t realize their pseudoscientific nature. This myth is especially dangerous in the education sector. One, students might be taught material in ways that aren’t effective. Since “right-brain/left-brain” teaching methods have not been validated, nor have supporting evidence (Bruer, 2002), it would then be completely erroneous to adopt a “right-brain/left-brain” teaching. This belief can restrict and limit people’s abilities and personality. This neuromyth may be internalized and can impact self-efficacy. It could even lead to self-fulfilling prophecies. Bandura 1994
The Myth of the Origin and Supporting Evidence. In the 1800s, Paul Broca and Carl Wernicke, two pioneers in the field of language production, demonstrated that comprehension and language production are controlled by two distinct brain regions. These were later named Wernicke’s and Broca’s areas. Broca’s and Wernicke argued that language is controlled by left-side brain regions. Robert Lewis Stevenson’s book “Dr. Jekyll & Mr. Hyde” (1886). Waters, 2017, p. 58). He explored human nature’s dualities in his work. Dr. Jekyll had a logical right brain and Mr. Hyde had an emotional left brain (Waters, 2017).
The whole left-brain-right-brain obsession died down with the advent of the 20th century. This was until Roger Sperry’s split brain experiments in the 1960s, which earned him the Nobel Peace Prize. This myth was first created by participants with brain functions that were not typical. It was intended to learn more about epilepsy (Lienhard 2017). Sperry’s original work, which revealed the functional differences between the right and left brain hemispheres, is still valid. However the results have been exaggerated and misunderstood.
Sperry’s former student Michael Gazzaniga created the “Interpreter Phenomenon”. Gazzaniga observed his fellow colleagues observe patients when the left and right halves could not communicate. They were given an image in the right visual area that corresponds with the left-brain, and they were able explain it. Patients were not able point to similar objects when the image was shown to their left visual fields. Gazzaniga speculated that while the right brain was able to see the image it required the left brain to respond verbally. Gazzaniga therefore characterized Gazzaniga’s left hemisphere “inventive, interpreting” (Gazzaniga and 2015). If you don’t have a good understanding of brain processes, it is easy to misinterpret and simplify this statement. Sperry (1984), warns the public: “…experimentally found polarity in left-left cognitive mode is an idea that is easy to misunderstand. It is important to remember, however, that the two brain hemispheres are often used together in a normal intact brain.
It is absurd to say an individual is right-brained or left-brained. However, Perry’s and other studies have misunderstood brain lateralization to be linked with personality traits and mental states. This simplified view of complex neuroscience could be due to our human instinct to grasp things we don’t understand, and to accept simplified narratives in spite of warnings. The brain is not in constant tug-of-war. The hemispheres should be seen as systems.
Evidence Against MythBrain scans have shown no evidence that there is sidedness. Instead, activity occurred on both the left and right sides depending on the task. (Nielsen. Zielinski. Ferguson. Lainhart & Anderson. 2013). The study compared 3D images of more than 1,000 brains to determine the activity of each hemisphere using an MRI scanner. Both sides of brain were involved in cognitive processes. This supports the absence of selective simulation (Lindell (2011)).
It is widely believed that creativity is a “right brain” process. Another popular belief is that creativity is a right-brain process and that people who are “right-brained,” are more creative than their left-brained counterparts. Both sides of the brain can be involved in creative tasks (Runco 2004 p. 665). As previously mentioned, the “interpreter phenomenon”, or lack thereof, shows that creativity is not limited to the left hemisphere. This is especially true when logical tasks demand creativity. In fact, creativity can be rooted in logical reasoning. People in creative professions have greater interaction with both sides than people in noncreative fields (Gibson Folley & Park, 2009).
Brain lateralization refers to a complex and ongoing process in which different brain regions “specialize” in specific cognitive skills and behaviors. Although there are two hemispheres in the brain, they work together and interact with each other (Noggle & Hall 2011, 2011). Noting that there is no relationship between personality traits and laterization, it is important to remember. Therefore, no one can be fully left-brained or right-brained (Sperry 1961). It is possible to rewire a healthy brain’s lateralized functions, such language, into the other side of the brain, particularly if the patient are very young. An increase in latezization and plasticity can be seen before an activity is developed and then again after it has been developed (Ressel Wilke. Wilke. Lidzba. Lutzenberger. 2008). Children with brain damage to their left hemisphere can still live normal lives. Children with brain damage to their left hemisphere may still be able to develop language. Damage is not detected by age 7.
This simplistic idea that tasks are dominated only by one side is not supported by science. Even the popular lore that brains have a tendency to be more creative and logical than the other was not true. Each hemisphere plays a critical role in the execution of tasks. While some functions are more concentrated in one hemisphere than others, their overall function does not depend on one hemisphere as the hemispheres do not work in isolation. This myth is created because it simplifies brain function classifications into simple dichotomies (“left brain vs. right brain”), and ignores the complex working relationships of the brain.
Citations
Bandura, A. (1994). Self-efficacy. In V. S. Ramachaudran (Ed. Encyclopedia of human behaviour (Vol. 4, pp. 71-81). Academic Press, located in New York. (Reprinted with permission of H. Friedman. (Reprinted in H. Friedman [Ed. San Diego: Academic Press, 1998).
Bruer, J. T. (2002). Avoiding the mistake of the pediatrician: How neuroscientists could help educators (and them). Nature Neuroscience (Supplement), 5, 1031-1033.
Dundar S. and Gunduz N. (2016). Misconceptions Concerning the Brain: Preservice Teachers’ Neuromyths. Mind, Brain, and Education, 10: 212-232. doi:10.1111/mbe.12119
Gazzaniga, M. S. (2015). Tales from both sides: A life in Neuroscience (1st Ed.) New York, NY: Ecco Press.
Gibson, C., Folley, B. S., & Park, S. (2009). Study of near-infrared and behavioral spectroscopy to examine enhanced divergent thinking and creativity among musicians. Brain and Cognition published a study in which 69 participants were examined and the results indicated that cognitive processes have an effect on the functioning of the brain (162-169).
Lienhard, D. A. December 27th, 2017 Roger Sperry’s split brain experiments (1959-1968). An encyclopedia of information on the Embryo Project is available. Retrieved from http://embryo.asu.edu/handle/10776/13035.
Lindell, A. K. (2006). In your right brain: Contributions of the right hemisphere to language production and processing. Neuropsychology Review published a paper exploring the effects of mental health disorders on the brain, looking at the neurological processes involved. The study compared the physical and cognitive changes that occur with different mental illnesses to understand how they interact with the brain. The findings showed that there is a complex relationship between mental health disorders and the brain’s physical and cognitive functioning. The paper concluded that further research is necessary to gain a better understanding of the neurological processes involved in mental health disorders.
Nielsen J.A., Zielinski B.A., Ferguson M.A., Lainhart J.E., Anderson J.S. (2013). Evaluation of the left-Brain/right-Brain Hypothesis with Resting State Functional Connectivity Magnetic Resonance Imaging. A study published in PLoS ONE in 2013 (8(8), e71275) found that… https://doi.org/10.1371/journal.pone.0071275
Noggle C.A. Hall J.J. (2011) Hemispheres of the Brain. In: Goldstein S., Naglieri J.A. Edited by a team of experts, the Encyclopedia of Child Behavior and Development provides comprehensive coverage of the field. Springer Publishing, located in Boston, Massachusetts
Pines M. (1973). Our heads are home to two very different individuals. The Sunday Magazine New York Times. from https://www.nytimes.com/1973/09/09/archives/we-are-leftbrained-or-rightbrained-two-astonishingly-different.html
Reilly, J., Losh, M., Bellugi, U., & Wulfeck, B. (2004). Frog, where’s your frog? Children with Williams Syndrome, early focal injury to the brain and language impairments may have narratives. The relationship between brain and language was explored in a study published in Brain and Language, with the results of the research being reported in an 88th issue of the journal. The paper detailed how the two are interconnected, with the findings being spread across 229 to 247 pages.
Runco, M. A. (2004). Creativity. The Annual Review of Psychology recently published a review of 55 studies, examining various topics and exploring their effects on psychology. The review covered a range of topics, from psychological processes to the influence of environmental factors, and the results were published in a 657-687 page article.
Society for Neuroscience (2009. Juni). Neuroscience Research in Education Summit. The Promise of Interdisciplinary Collaborations between Brain Sciences, Education. The University of California, Irvine (UCI). June 22-24, 2009. http://www.ndcbrain.com/articles/SocietyforNeuroscience-EducationSummitReport.pdf
Sperry, R. W. (1961). Cerebral Organization & Behavior. Science, 133, 1749-1757. http://people.uncw.edu/puente/sperry/sperrypapers/60s/85-1961.pdf
Sperry, R.W. (1984). The divided brain, consciousness and personal identity. Neuropsychologia, 22, 661-673.
Waters, E. (2017). Waters, Elizabeth: The left-brain vs. the right-brain myth. [Video file]. Retrieved from https://ed.ted.com/lessons/the-left-brain-vs-right-brain-myth-elizabeth waters#discussion
