fbpx
Free Consultation

Edublox Online Dyslexia Tutoring: We Target Two Core Brain Areas

Table of contents:


.
Ideas connecting dyslexia to brain functioning or brain lesions were already conveyed in the late 19th century by Berlin (Opp, 1994), Morgan (1896), and Hinshelwood (1895). Autopsy studies in the 1980s and 90s of persons with documented histories of dyslexia seemingly confirmed these long-held beliefs.

Specifically, Galaburda and colleagues (1985) reported several anatomical anomalies in the brains of a few persons with reading difficulties. Although those findings are intriguing, they are far from decisive. The samples were extremely small (a total of 4 men and 3 women) and included participants with evidence for neurological or psychiatric conditions and participants with impairments not limited to written language, who should have been excluded from a study purporting to examine brain correlates of dyslexia. The control group was also very small, effectively precluding reliable estimation of the specificity of any findings.

However, at the time and during the preceding decades, people were also convinced that the brain is hardwired. The prevailing theory was that if a part of the brain was damaged due to an injury, or if a person was born with a mental condition, nothing could be done (Keshav, 2018). This contributed to the opinion that dyslexia is a lifelong condition — “like alcoholism … it can never be cured” (Clark & Gosnell, 1982).

Neuroplasticity: An extraordinary discovery

A 1998 landmark study found that the human brain has the ability to generate new neurons (Eriksson et al., 1998). This research challenged the prevailing theory that the human brain is a rigid system, that humans are born with all of their brain cells, and that we lose brain cells daily which our brain does not replace with new ones. More research studies followed, demonstrating that the brain is malleable and adaptable — or plastic — and even that it can grow.

In a classic experiment, Maguire et al. (2000) compared the brains of London taxi drivers with a control group of non-taxi drivers. Maguire first got the idea to study London cab drivers from research on the memory champions of the animal world. Some birds and mammals, such as western scrub jays and squirrels, cache food and dig it up later, which means they must memorize the locations of all their hiding spots. Researchers noticed that the hippocampus, which is crucial for long-term memory and spatial navigation, was much larger in these animals than in similar species that did not secret away their snacks. In some species, hippocampal volumes enlarge specifically during seasons when the demand for spatial ability is greatest. This interesting fact led Maguire to wonder whether the hippocampus would grow in people who had to memorize lots of visual locations, such as London cab drivers who have to memorize roughly 25,000 city streets, as well as thousands of tourist attractions and hot spots, before earning their cab licenses.

The results showed that London taxi drivers had significantly larger posterior hippocampi than the controls (Maguire et al., 2000) as well as London bus drivers (Maguire et al., 2006). Contrary to taxi drivers, who must navigate through various routes around the city, bus drivers have to follow only a limited, predetermined set of routes. Furthermore, years of navigation experience correlated with hippocampal gray matter volume in taxi drivers.

Similar findings of apparently environmentally driven plasticity, with positive correlations between gray matter and the time spent learning and practicing their specialization, have been reported in several other groups including musicians (Sluming et al., 2002), jugglers (Draganski et al., 2004), and bilinguals (Mechelli et al., 2004). A study by Skeide and colleagues (2017) shows that, when adults learn to read for the first time, the changes that occur in their brain are not limited to the outer layer of the brain, the cortex, but extends to deep brain structures in the thalamus and the brainstem. The last-mentioned study was conducted with illiterate Indian women who learned how to read and write for six months.

The studies mentioned above and many others confirm that the brain can change, and even that an injured brain can be rewired. The healthy portions of a damaged brain can be trained to assume the functions of the dysfunctional tissue (Nudo, 2013; Kadosh & Walsh, 2006).

The “reading” brain

Data using fMRI indicate three neural systems for reading (shown in the image above). These are all located in the left side of the brain: one in the front of the brain (shown in green, in the region of the inferior frontal gyrus [Broca’s area]) and two in the back of the brain (one in the parietotemporal region, shown in red, and a second in the occipito-temporal region, shown in yellow). The latter system is of particular importance for skilled, fluent reading and is termed the visual word-form area (Shaywitz, 2005).

Research shows that a network of brain regions is involved in learning to read, one specifically in sounding out words, and another in seeing words as pictures. The left inferior parietal lobule (shown in red) is said to be involved in word analysis, grapheme-to-phoneme conversion, and general phonological and semantic processing. The picture area is located in the left occipitotemporal region (shown in yellow), and is known as the visual word form area (VWFA) or visual dictionary.

Neuroscientists at Georgetown University Medical Center discovered that skilled readers can recognize words at lightning-fast speed when they read because the word has been placed in a sort of visual dictionary (Glezer et al., 2016). This function of the brain was already identified by James Hinshelwood in 1917.

Glezer and her coauthors tested word recognition in 27 volunteers in two different experiments using fMRI. They were able to see that words that were different, but sound the same — like ‘hare’ and ‘hair’ — activate different neurons, akin to accessing different entries in a dictionary’s catalog. If the sounds of the word had any influence in this part of the brain, we would expect to see that they activate the same or similar neurons. This, however, was not the case — ‘hair’ and ‘hare’ looked just as different as ‘hair’ and ‘soup’. In addition, the researchers found a different distinct region that was sensitive to the sounds, where ‘hair’ and ‘hare’ did look the same. The researchers thus showed that the brain has regions that specialize in doing each of the components of reading: one region is doing the visual piece and the other is doing the sound piece.

These findings negate the dual-access theory which suggests that visual word recognition in skilled readers is not based on visual processing alone, but that we access both the phonology and the visual perception of a word (Frost, 1998).

Brain imaging also reveals compensatory overactivation in other parts of the reading system (shown in green). The compensatory neural systems allow a dyslexic person to read more accurately. However, the critical visual word-form area remains disrupted and difficulties with rapid, fluent, automatic reading persist. The dyslexic continues to read slowly (Shaywitz, 2005).

Edublox’s Live Tutor targets both brain regions

Brain areas involved in learning to read: The VWFA or visual dictionary and the sounding out area.

Both brain areas, mentioned above, must be trained in the teaching of reading, and Live Tutor aims at doing just that. Our program is based on the Orton-Gillingham approach, which is excellent at developing the left inferior parietal lobule (the sound piece), but our program simultaneously targets the brain’s VWFA or visual dictionary.

Practicing “nonsense words” does not feature in Edublox programs as this counters developing the brain’s VWFA or visual dictionary. “Nonsense words” are letter sequences that follow regular phonetic rules and are pronounceable, but have no meaning — for example, bif or yom or mig. Many schools have implemented tools to measure early reading ability, which include tests of the ability to decode nonsense words (Marshall, 2019). However, it has now also become a skill that is increasingly being taught directly, especially in Orton-Gillingham-based programs. We consider teaching “nonsense words” as detrimental to reading and even more so to spelling. Maybe, just maybe, educators should reconsider this practice.  
.

NEXT: Page 5: Learning principles are fundamental


.
Our live online tutoring services are offered to students based in the United States, Canada, Australia, New Zealand, and elsewhere. Book a free consultation to discuss your child’s learning needs.
.


.
References and resouces:

Clark, M., & Gosnell, M. (1982, March 22). Dealing with dyslexia. Newsweek, 55-56.

Draganski, B., Gaser, C., Busch, V., Schuierer, G., Bogdahn, U., & May, A. (2004). Neuroplasticity: Changes in grey matter induced by training. Nature, 427, 311-312.

Eriksson, P. S., Perfilieva, E., Björk-Eriksson, T., Alborn, A., Nordborg, C., Peterson, D. A., & Gage, F. H. (1998). Neurogenesis in the adult human hippocampus. Natural Medicine, 4(11), 1313-1317.

Frost, R. (1998). Toward a strong phonological theory of visual word recognition: True issues and false trails. Psychological Bulletin, 123(1), 71-99.

Galaburda A. M., Sherman G. F., Rosen G. D., Aboitiz F., & Geschwind N. (1985). Developmental dyslexia: Four consecutive patients with cortical anomalies. Annals of Neurology, 18, 222–233.

Glezer, L. S., Eden, G, Jiang, X., Luetje, M., Napoliello, E., Kim, J., & Riesenhuber, M. (2016). Uncovering phonological and orthographic selectivity across the reading network using fMRI-RA. Neuroimage, 138, 248-256.

Hinshelwood, J. (1895). Word-blindness and visual memory. Lancet, 146(3773), 1564-1570.

Hinshelwood, J. (1917). Congenital word-blindness. London: Lewis.

Kadosh, R. C., & Walsh, V. (2006). Cognitive neuroscience: Rewired or crosswired brains? Current Biology, 16(22), R962-963. https://doi.org/10.1016/j.cub.2006.10.017 

Keshav, M. (2018). The life transforming power of NLP. Chennai: Notion Press.

Maguire, E. A., Gadian, D. G., Johnsrude, I. S., Good, C. D., Ashburner, J., Frackowiak, R. S. J., & Frith, C. D. (2000). Navigation-related structural change in the hippocampi of taxi drivers. Proceedings of the National Academy of Sciences of the United States of America, 97(8), 4398-4403. https://doi.org/10.1073/pnas.070039597

Maguire, E. A., Woollett, K., & Spiers, H. J. (2006). London taxi drivers and bus drivers: A structural MRI and neuropsychological analysis London taxi drivers and bus drivers. Hippocampus, 16(12), 1091-1101.

Marshall, A. (2019). The nonsense of teaching nonsense words. Retrieved June 2, 2021 from https://blog.dyslexia.com/nonsense-teaching-words/

Mechelli, A., Crinion, J. T., Noppeney, U., O’Doherty, J., Asburner, J., Frackowiak, R. S., & Price, C. J. (2004). Structural plasticity in the bilingual brain. Nature, 431, 757.

Morgan, W. P. (1896). A case of congenital word blindness. The Lancet, 2(1871), 1378.

Nudo, R. J. (2013). Recovery after brain injury: Mechanisms and principles. Frontiers in Human Neuroscience, 7(887). https://doi.org/10.3389/fnhum.2013.00887

Opp, G. (1994). Historical roots of the field of learning disabilities: Some nineteenth-century German contributions. Journal of Learning Disabilities, 27, 10-19.

Reiff, H. B., & Gerber, P. J. (1992). Adults with learning disabilities. In N. N. Singh, & I. L. Beale (Eds.), Learning disabilities: Nature, theory, and treatment (pp. 170-198). New York: Springer-Verlag.

Reiff, H. B., Ginsberg, R., & Gerber, P. J. (1995). New perspectives on teaching from successful adults with learning disabilities. Remedial and Special Education, 16(1), 29-37.

Shaywitz, S. (2005). Overcoming dyslexia. New York: Vintage Books.

Skeide, M. A., Kumar, M., Mishra, R. K., Tripathi, V .N., Guleria, A., Singh, J .P., … Huettig, F. (2017). Learning to read alters cortico-subcortical cross-talk in the visual system of illiterates. Science Advances, 3(5), e1602612. https://doi.org/10.1126/sciadv.1602612

Sluming, V., Barrick, T., Howard, M., Cezayirli, E., Mayes, A., & Roberts, N. (2002). Voxel-based morphometry reveals increased gray matter density in Broca’s area in male symphony orchestra musicians. Neuroimage, 17(3), 1613-1622.