Brain Myths Busted: What Science REALLY Says About Your Brain (And Why It Matters for Learning!)
3 Neuromyths About Brain Lateralization and Specific Functions
1. The Left and Right Brain Hemispheres Are Dominant for Specific Types of Thinking (Logical vs. Creative)
Description and Origin: This belief claims people can be categorized as "left-brained" (logical, analytical, language-oriented) or "right-brained" (creative, intuitive, visually-oriented), and these differences dictate their thinking or learning style.
This myth originated from research in the 1960s and 70s, particularly Roger Sperry's studies on split-brain patients, which showed that brain hemispheres have certain specialized functions (e.g., the left hemisphere is more involved in language for most people). However, these observations were oversimplified and exaggerated by popular culture, self-help books, and educational programs, leading to the idea that people have a dominant hemisphere defining their personality or cognitive abilities.
Scientific Explanation: While brain hemispheres do exhibit some functional specializations (for instance, the left hemisphere is more associated with language processing and the right with spatial abilities in right-handed individuals), complex thought—whether logical or creative—requires the collaboration of both hemispheres.
Neuroimaging studies, such as those using functional magnetic resonance imaging (fMRI), show that creative tasks (e.g., composing music) and analytical tasks (e.g., solving math problems) activate neural networks distributed across the entire brain, including both hemispheres (Nielsen et al., 2013).
The idea of a "logical" versus "creative" dichotomy ignores the complexity of brain networks and the functional integration across the corpus callosum, which connects the hemispheres (Gazzaniga, 2000). The reality is that our personality and abilities emerge from the complex interaction of multiple brain regions. There's no scientific evidence proving that one hemisphere dominantly controls our way of being or our aptitudes.
Key References:
Gazzaniga, M. S. (2000). Cerebral specialization and interhemispheric communication: Does the corpus callosum enable the human condition? Brain, 123(7), 1293–1326.
https://doi.org/10.1093/brain/123.7.1293 Authored by a leading neuroscientist, this article analyzes how brain specialization and interhemispheric communication (via the corpus callosum) contribute to complex cognitive functions and human consciousness. It emphasizes the critical role of interhemispheric integration for human awareness and behavior.
Nielsen, J. A., Zielinski, B. A., Ferguson, M. A., Lainhart, J. E., & Anderson, J. S. (2013). An evaluation of the left-brain vs. right-brain hypothesis with resting state functional connectivity magnetic resonance imaging. PLoS ONE, 8(8), e71275.
https://doi.org/10.1371/journal.pone.0071275 This study directly evaluates the popular "left-brain vs. right-brain" hypothesis using resting-state fMRI. It definitively concludes that there are no individuals with global dominance of one hemisphere; instead, both hemispheres work together in most cognitive tasks.
Corballis, M. C. (2014). Left brain, right brain: Facts and fantasies. PLoS Biology, 12(1), e1001767.
https://doi.org/10.1371/journal.pbio.1001767 An expert in brain lateralization reviews the myths and realities. He explains that while functional differences exist between hemispheres, the idea of people being "left-brained" or "right-brained" is an oversimplified myth not supported by scientific evidence.
Consequences in Education:
Mislabeling Students: Categorizing students as "left-brained" (logical) or "right-brained" (creative) can limit their exposure to balanced education, restricting activities that could develop complementary skills. For example, a student labeled "creative" might avoid analytical subjects like math.
Ineffective Teaching Practices: Educational programs designed to stimulate a specific hemisphere (e.g., "right-brain training" exercises to foster creativity) lack scientific support and divert resources from more effective approaches, such as interdisciplinary learning.
Reinforcement of Stereotypes: This myth can perpetuate erroneous ideas about students' capabilities, affecting their self-esteem and motivation. For example, a student labeled "not logical" might feel incapable of tackling STEM subjects.
Neglecting Cognitive Integration: Focusing on one hemisphere ignores the importance of activities that promote the integration of logical and creative skills, such as critical thinking or complex problem-solving, which are essential for deep learning.
2. Gray Matter is More Important Than White Matter
Description and Origin: This misconception suggests that gray matter, primarily composed of neuron cell bodies, is more crucial for learning and cognition than white matter. White matter, in fact, consists of myelinated axons that connect different brain regions. This mistaken idea stems from an overly simplistic understanding of neuroanatomy, where gray matter is perceived as the brain's "processing center," underestimating white matter as mere "wiring." MRI images, which often highlight gray matter in cognitive processing, have contributed to this imprecise perception.
Scientific Explanation: Both gray matter and white matter are equally crucial for brain function and learning. Gray matter is primarily located in the cerebral cortex and subcortical nuclei; it contains neuron cell bodies and is involved in information processing, such as perception, decision-making, and memory.
White matter is composed of myelin-sheathed axons; it facilitates the rapid and efficient transmission of signals between brain regions, enabling information integration (Fields, 2008).
Diffusion Tensor Imaging (DTI) studies have shown that the integrity of white matter is directly related to cognitive abilities, such as processing speed and working memory (Schmithorst et al., 2005). For instance, alterations in white matter, as observed in disorders like multiple sclerosis, can severely affect cognition.
Brain plasticity, essential for learning, depends on changes in both gray matter (e.g., synaptic strengthening) and white matter (e.g., experience-induced myelination) (Zatorre et al., 2012).
Key References:
Fields, R. D. (2008). White matter in learning, cognition and psychiatric disorders. Trends in Neurosciences, 31(7), 361–370.
https://doi.org/10.1016/j.tins.2008.04.001 A prominent neuroscience researcher reviews the role of white matter in learning, cognition, and psychiatric disorders. He highlights that white matter is fundamental for efficient communication between brain regions, and its alteration can impact learning and be associated with mental disorders.
Schmithorst, V. J., Wilke, M., Dardzinski, B. J., & Holland, S. K. (2005). Cognitive functions correlate with white matter architecture in a normal pediatric population: A diffusion tensor MRI study. Human Brain Mapping, 26(2), 139–147.
https://doi.org/10.1002/hbm.20149 Based on diffusion tensor MRI studies, this article demonstrates that the architecture of brain white matter in healthy children correlates with cognitive functions like memory and reasoning. It suggests that the development and organization of white matter are crucial for cognitive performance in childhood.
Zatorre, R. J., Fields, R. D., & Johansen-Berg, H. (2012). Plasticity in gray and white: Neuroimaging changes in brain structure during learning. Nature Neuroscience, 15(4), 528–536.
https://doi.org/10.1038/nn.3045 These experts in neuroplasticity review how learning induces structural changes in both gray and white matter of the brain, observed through neuroimaging. They explain that brain plasticity involves not only changes in neurons but also in the connections and communication pathways (white matter).
Consequences in Education:
Underestimation of Connectivity Strategies: This myth can lead educators to focus solely on activities that stimulate cognitive processing (associated with gray matter) and neglect strategies that promote information integration, such as interdisciplinary learning or spaced practice, which rely on efficient white matter-mediated connections.
Misunderstandings About Brain Development: Educators might underestimate the importance of stimulating environments that promote myelination and brain connectivity, like motor activities or multisensory experiences, which are crucial for early learning.
Inadequate Intervention Design: By prioritizing gray matter, educational programs might overlook interventions that improve processing speed or brain connectivity, such as exercises that foster coordination or complex problem-solving.
Lack of Attention to White Matter-Related Disorders: This myth can lead to misunderstandings about learning disorders involving white matter alterations, such as ADHD, which could delay the implementation of appropriate support.
3. Dyslexia Is Just Seeing Letters Backwards
Description and Origin: This belief simplifies dyslexia as a visual perception problem where individuals "see letters backward" or confuse letters like "b" and "d." This idea likely stems from initial observations of children with dyslexia making reversal errors in writing or reading, combined with a limited understanding of dyslexia in early research. The idea was perpetuated by popular descriptions and erroneous media representations that ignored the disorder's complexity.
Scientific Explanation: Dyslexia is a neurodevelopmental disorder that primarily affects phonological processing—that is, the ability to associate sounds with letters and written words.
Various neuroimaging studies have shown that individuals with dyslexia exhibit differences in brain regions like the left superior temporal gyrus and Broca's area, which are involved in language processing and phonological decoding (Shaywitz & Shaywitz, 2005).
While some children with dyslexia may make reversal errors (e.g., writing "b" instead of "d"), these are not the primary cause of the disorder but rather an occasional symptom that can also be observed in children without dyslexia during early learning stages (Vellutino et al., 2004).
Dyslexia affects reading fluency, comprehension, and spelling, and it's influenced by genetic and environmental factors. Interventions based on explicit instruction in phonological skills, such as segmenting and blending sounds, have proven effective in improving reading abilities in students with dyslexia (Torgesen et al., 2001).
Key References:
Shaywitz, S. E., & Shaywitz, B. A. (2005). Dyslexia (specific reading disability). Biological Psychiatry, 57(11), 1301–1309.
https://doi.org/10.1016/j.biopsych.2005.01.043 Authored by two influential researchers in dyslexia, this article reviews advancements in understanding dyslexia, highlighting its neurobiological basis. It explains that dyslexia is a specific reading learning disorder associated with differences in phonological processing and brain structure and function.
Torgesen, J. K., Alexander, A. W., Wagner, R. K., Rashotte, C. A., Voeller, K. K. S., & Conway, T. (2001). Intensive remedial instruction for children with severe reading disabilities: Immediate and long-term outcomes from two instructional approaches. Journal of Learning Disabilities, 34(1), 33–58.
https://doi.org/10.1177/002221940103400104 This highly cited article in the literature on reading difficulty intervention evaluates the short-term and long-term effects of two intensive instructional methods for children with severe dyslexia. It concludes that intensive, structured instruction can significantly improve reading, though some deficits may persist.
Vellutino, F. R., Fletcher, J. M., Snowling, M. J., & Scanlon, D. M. (2004). Specific reading disability (dyslexia): What have we learned in the past four decades? Journal of Child Psychology and Psychiatry, 45(1), 2–40.
https://doi.org/10.1111/j.1469-7610.2004.00305.x This article reviews four decades of dyslexia research. It summarizes key findings on its causes, diagnosis, and treatment, emphasizing the importance of phonological processing and early intervention for improving reading outcomes.
Consequences in Education:
Delayed Diagnosis and Support: The belief that dyslexia is just a visual problem can delay proper identification of the disorder, as educators might not recognize symptoms related to phonological processing, such as difficulties segmenting words or reading fluently.
Inadequate Interventions: Students with dyslexia might receive interventions focused on visual perception (e.g., eye-tracking exercises or colored lenses) that don't address the core of the problem, wasting time and resources.
Stigmatization and Low Self-Esteem: Students with dyslexia might be misunderstood as "lazy" or "inattentive" due to the simplification of the disorder, affecting their motivation and confidence in their learning abilities.
Lack of Evidence-Based Strategies: This myth can lead educators to ignore effective interventions, such as structured phonological instruction or intensive reading programs, which are essential for supporting students with dyslexia.
