Reading and writing borrow the brain's speech and movement circuits
Eddie Chang on reading and dyslexia, Erich Jarvis on reading, writing and inner speech, and Jared Diamond on how writing was invented all treat literacy as a recent skill built on older machinery. It helps explain why reading must be taught explicitly and why some children struggle with it.
Why must reading be taught while speech is picked up? Show answer
Speech is evolved and hardwired, while reading is a recent invention mapped onto older brain systems.
What is the visual word form area? Show answer
A region where the temporal lobe meets the visual cortex that becomes very sensitive to seeing words in people who read.
Where does the written word go after the visual cortex, according to Eddie Chang? Show answer
The brain maps it onto the area that makes sense of the sounds of words, called phonology.
What lies behind many cases of dyslexia, in Chang's account? Show answer
A problem of phonological awareness, though he says the cause may be visual, phonological or both depending on the case.
Why can dyslexia be hard to spot? Show answer
The child may understand everything said aloud, because the brain compensates through pattern recognition.
Which three pathways does Erich Jarvis say reading uses? Show answer
The visual pathway, the speech motor pathway and the auditory pathway.
What physical evidence shows that silent reading engages the speech system? Show answer
Electrodes on the laryngeal muscles pick up activity while a person reads silently.
What does writing add to the circuits used for reading? Show answer
The hand areas, which sit next to the speech pathway, making at least four circuits.
How many times was writing independently invented, according to Jared Diamond? Show answer
Three, with Easter Island a possible fourth. Other systems were copied, adapted or inspired by the idea.
What does the story of Linear B show? Show answer
That writing can be lost. Greece went without it after the Bronze Age collapse until adopting the Phoenician alphabet.
Where do Chang and Jarvis differ on skilled reading? Show answer
Jarvis has readers silently speaking what they read. Chang says skilled readers build a direct route from word to meaning.
What practical tip follows for writing? Show answer
Use a tool whose speed matches the speech in your head, and stop talking while you write.