Beyond Binary Wikia
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Research

Cross-Cultural

|Nature:/2004/Chinese dyslexics have problems of their own>

"There is no one cause for dyslexia: rather, the causes vary between languages. So conclude researchers who have found that Chinese children with reading difficulties have different brain anomalies to their Western counterparts[1]."[2]

"The finding explains why one can be dyslexic in one language but not another. [...] Speakers of alphabetic languages, such as English or Russian, can have a problem converting letters into sounds. Dyslexics in these languages have reduced activity in a brain region called the left temporoparietal cortex.

But Chinese readers must learn the meanings of around 5,000 different characters, each corresponding to a word. Instead of letter-to-sound conversion problems, Chinese dyslexics have difficulties extrapolating from a symbol's shape to its sound and meaning."

"The finding could also explain the rare cases of people who read normally in one language, but are dyslexic in another. For example, one bilingual boy has reading problems in English, but none in Japanese[3].

Japanese is a halfway house between alphabetic languages and Chinese. Readers often have to match shapes to syllables, a different task that is likely to involve a third, as yet unidentified brain region. So the boy’s left temporoparietal cortex was probably under active, whilst the unknown Japanese language-related area was fine, says Eden."[2]

|TheEconomist:/2014/Disability of a different character>

"FOR a foreigner, learning how to read in Chinese sometimes feels like spot-the-difference: one of those children’s puzzles where you have to find tiny dissimilarities in two nearly identical pictures.

Take the character for “special” (特) and the one for “grasp” (持), for example, which are the same apart from a small extra stroke on the left hand side of the former and a tiny upward tick at the bottom of the long vertical stroke of the latter. Those (to a foreign eye) tiny differences give them distinct meanings. They are also pronounced quite differently: the first “te” (falling tone), the other “chi” (rising tone). The first time I encountered the two characters my response was rather childish: it’s just not fair."

"For an unlucky minority, the characters never quite stick as they should, just as a significant minority of people elsewhere have problems learning to read alphabetic languages. Dyslexia is characterised as a severe reading problem in people with normal intelligence and schooling. According to Dyslexia International, a charity, an estimated 5-15% of the population suffer from it, depending on the criteria used to define dyslexia. That means about 700 million people worldwide display some of its traits."[4]

"Chinese reading uses more of a frontal part of the left hemisphere of the brain (called the left middle frontal region), whereas reading languages with an alphabet uses a posterior part of the brain (the left temporoparietal region).

Learning to read a language with an alphabet requires learning to sound out words; the visual form maps on to the sound of the word. Chinese, by contrast, maps the graphic form, the character, on to the meaning. The phonetic sound of the character does not necessarily correspond to the form of it. Reading English requires sounding out words segment by segment. The letter-sound conversion does not apply in Chinese."[4]

Accessible Fonts

https://www.dyslexiefont.com/en/typeface/?fbclid=IwAR2S0D4FgUCcsVnnD55uNbB5yPPzS009W6zDa7HJXkSKkregNlVCYI9o3V4

"The most common reading errors of dyslexia are swapping, mirroring, changing, turning and melting letters together. In the Dyslexie font, every letter is uniquely shaped, eliminating the common reading errors of dyslexia. The innovative font increases the ease of reading for people with dyslexia, meanwhile offering non-dyslectics some reading benefits as well."

Related Conditions

(coming soon)

Dyscalculia

(coming soon)

Dysgraphia

(coming soon)

Dyspraxia

(Not really related, but oh well, coming soon)

https://theconversation.com/dyspraxia-is-more-than-just-clumsy-child-syndrome-it-can-cause-emotional-distress-and-anxiety-throughout-life-66948/

"Adults with DCD still bump into objects and continue to struggle with handwriting. They may also have trouble with timekeeping and planning ahead, meaning they may be frequently late to work and social events. Self-care is also a problem, but rather than fastening clothes it turns into struggling to keep a home tidy. Tasks such as preparing a meal from scratch and ironing clothes can also be troublesome. DCD adults can also have issues with learning a new skill that requires speed and accuracy – so it can be difficult for them to learn to drive a car."

https://www.thesaturdaypaper.com.au/life/health/2019/01/25/dyspraxia-or-developmental-co-ordination-disorder/15483730937330

Mirror Writing

(coming soon)

https://en.wikipedia.org/wiki/Mirror_writing

"Leonardo da Vinci wrote most of his personal notes in mirror, only using standard writing if he intended his texts to be read by others. The purpose of this practice by Leonardo remains unknown, though several possible reasons have been suggested. For example, writing left handed from left to right would have been messy because the ink just put down would smear as his hand moved across it. Writing in reverse would prevent such smudging."[5]

Mirror writing: neurological reflections on an unusual phenomenon (TW: pathologisation of neurological differences)

"I gave an account of an epileptic girl who used to write with the left hand, in reverse order, and with the forms of the letters reversed as well—and [she wrote] fluently, too—in such a way that what she wrote could only be read when placed before a mirror …. But a few years ago … I observed a centurion who, having lost his right arm in action, wrote all his letters with the left hand, with order and form similarly reversed, with the highest degree of fluency … one who wished to read his writing had to hold it to a mirror.1

Three hundred years ago, Lentilius described the first known cases of pathologically acquired mirror writing, but mirror writing had been observed a long time earlier."[6]

Mirror Writing, Left-handedness, and Leftward Scripts

"Pathological left-handed mirror writing in children has long been noted to be particularly common in dyslexia or more nonspecific “learning difficulties.” In adults, pathologically acquired mirror writing most commonly occurs in focal diseases affecting the left hemisphere, in particular a stroke that results in a right hemiplegia when writing with the left hand becomes necessary."[7]

Neurology of Dyslexia

Neuronal Migration Hypothesis

|Ncbi.nlm.nih.gov://Guidi et al (2018)/The neuronal migration hypothesis of dyslexia: A critical evaluation 30 years on>

"For developmental dyslexia, early postmortem studies conducted in the 1980s linked the disorder to subtle defects in the migration of neurons in the developing neocortex. These early studies were reinforced by human genetic analyses that identified dyslexia susceptibility genes and subsequent evidence of their involvement in neuronal migration. In this review, we examine recent experimental evidence that does not support the link between dyslexia and neuronal migration. We critically evaluate gene function studies conducted in rodent models and draw attention to the lack of robust evidence from histopathological and imaging studies in humans. Our review suggests that the neuronal migration hypothesis of dyslexia should be reconsidered, and the neurobiological basis of dyslexia should be approached with a fresh start."
"The neuronal migration hypothesis of dyslexia is based on two key lines of evidence: functional genetics on a handful of susceptibility candidate genes in rodents, and postmortem histopathology in human dyslexia cases. In this review, we outlined a number of issues surrounding both of these points which, altogether, question the strength of the evidence in favour of the neuronal migration view. We make the case that this position is untenable in the face of our current knowledge of the function of candidate genes studied so far, the genetic architecture of dyslexia and human neuropathology, unless the original findings are replicated using modern standards."
"We do not question that disrupted neuronal migration can have important consequences for cognitive development in humans. The question is how far this specific aetiology is implicated in causing dyslexia, and how specific an aetiology it is."

Comorbidity

(see also Autism Comorbidities)

Co-Occurrence of Developmental Disorders: Children Who Share Symptoms of Autism, Dyslexia and Attention Deficit Hyperactivity Disorder

"There is only a small literature on the overlap in symptomology between autism spectrum disorders with those of dyslexia. Officially, as for ADHD, ASD is an exclusionary criterion for diagnosis of dyslexia and vice versa, but ASD also shows overlap with dyslexia in both cognitive and behavioural features (Reiersen & Todd, 2008, Simonoff et al., 2008). A proportion of children share symptoms between dyslexia, ADHD and ASD.

The number of children that do share symptoms of ASD and dyslexia is likely to be small (Wright, Conlon, Wright, & Dyck, 2011). The frequency of reading disorder in combination with disorder of written expression (i.e. dyslexia) was around 14% in a sample of adults with Asperger’s Syndrome (AS) so according to this result around one in seven individuals with AS will have co-occurring dyslexia (Hofvander et al., 2009). However the proportion of individuals with dyslexia who have co-occuring AS is likely to be low as Asperger’s Syndrome is much a rarer condition than dyslexia.

[...]

It is not just that ASD is co-morbid with dyslexia and ADHD. Other studies have noted high comorbidity with other developmental disorders. Dyspraxia and dyscalculia and conditions with shared symptoms such as specific language impairment are frequently comorbid with autism. Also dyslexia and ADHD themselves co-occur Willcutt and colleagues (Willcutt, Doyle, Nigg, Faraone, & Pennington, 2005) showed that 40% of a sample of twins with either dyslexia or ADHD was co-morbid for the other disorder. Reading difficulties were measured with both rating scale and an objective task in a study by Cheung et al. (2012) and correlations were observed among ADHD, reading difficulties and IQ. Over half, (53%-72%) of the overlapping familial influences between ADHD and reading difficulties were not shared with IQ. In a school based study Kadesjö and colleagues found 40% of children with ADHD showed reading problems and 29% writing problems (2005)."[8]

Fact Sheet: Dyslexia, a co-morbid [divergence] associated with Autism Spectrum [Divergences]

"Dyslexia is a condition or learning disability which causes difficulty with reading and writing. Its standard definition is a difficulty in reading and writing in spite of normal development of intelligence, cognitive and sensory abilities. Dyslexia is not limited to reversing the order of letters in reading or writing. Nor is it a visual perception deficit that involves reading letters or words backwards or upside down, as is often implied in popular culture.

Researchers have claimed that it is a brain-based condition with biochemical and genetic markers. Current scientific theories focus on the hypothesis that dyslexia stems from a deficit in phonological awareness. This hypothesis suggests that affected individuals have difficulty analyzing the words they hear into discrete segments (such as phonemes), which in turn leads to difficulty learning spelling-sound correspondences. [...]

Although they are different conditions, dyslexia co-occurs with attention deficit disorders (ADD or ADHD) at a rate of 30-50%."

Links

Richard Branson on Dyslexia as an Advantage

"Scientists estimate that dyslexia affects anywhere from 3% to 10% of the global population, but as Malcolm Gladwell points out in “David and Goliath,” a seemingly larger percentage of powerful businesspeople were born dyslexic and partially credit overcoming its challenges to their success."

References

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