If you look up stock images for dyslexia, one of the first shows a man chained to a giant metal ball with the condition written on it. Others show a child holding up a sign that says “help”. These are probably representative of the condition's image in society, but there are positive sides to developmental dyslexia that have been largely ignored – and all of us, dyslexic or not, may owe them an enormous debt.
A paper in Frontiers in Psychology notes that developmental dyslexia is defined by the World Federation of Neurology as; “A disorder in children who, despite conventional classroom experience, fail to attain the language skills of reading, writing and spelling commensurate with their intellectual abilities.” It's almost always treated as a neurobiological disorder and a deficit, albeit one that some talented people can overcome.
For forty years, however, some psychologists have questioned this view. Although there is no doubt that having developmental dyslexia makes some important things harder, Neurologist Norman Geshwind assembled evidence in the 80s that people diagnosed with developmental dyslexia tend to rank highly on skills beneficial for art, architecture and engineering.
In an era when Greta Thunberg calls autism her “superpower”, maybe it is time for reconsideration of dyslexia to go mainstream as well. Cambridge University's Dr Helen Taylor and Dr Martin Vestergaard propose that developmental dyslexia might be so common because it provided advantages to our ancestors. “The deficit-centred view of dyslexia isn’t telling the whole story,” Taylor said in a statement.
Taylor and Vestergaard think the developmental dyslexia's effect on reading is secondary to something deeper, which they call a cognitive search strategy favoring exploration over efficient exploitation of resources.
For a tribe of hunter-gatherers, the capacity to make good use of available food resources is obviously key. However, getting too good at exploiting local resources could prove a trap. Such a group would be unlikely to expand their range, physically or metaphorically, and could be in trouble when a disaster like a drought struck.
What every tribe needed then was an explorer, making the association between developmental dyslexia and explorative search strategies highly significant. According to the Complementary Cognition theory, if too many people were dyslexic in a population they might fail to make good use of familiar food sources, but a few ancestral dyslexic people improved the prospects of those around them.
In other words, neurobiological diversity was humanity's true superpower, particularly during periods of change such as climate instability.
This isn't just historical. Developmental dyslexia has a heritability of at least 60 percent. “Striking the balance between exploring for new opportunities and exploiting the benefits of a particular choice is key to adaptation and survival and underpins many of the decisions we make in our daily lives,” Taylor said.
Not all traits that served our ancestors well in the paleolithic are so useful today. The fact that one technology – reading – that causes trouble for people with a particular search strategy recently took over the world has changed the game. Nevertheless, Taylor and Vestergaard think developmental dyslexia could have more of a place if our institutions were less rigid.
“Schools, academic institutes and workplaces are not designed to make the most of explorative learning. But we urgently need to start nurturing this way of thinking to allow humanity to continue to adapt and solve key challenges,” Taylor said.
Interestingly, dyslexia is much more common than other forms of neurodiversity whose value has started to be reconsidered recently. Between 5 and 20 percent of the population has dyslexia to some degree – higher than autism or probably ADHD, for example, despite rising rates of diagnosis for both.