October is Dyslexia Awareness Month, making it a good time to revisit an intriguing chapter in the history of language and the brain: how the medical profession came to understand dyslexia. What began as a puzzling disconnect between vision and reading would eventually reveal that reading is far more than simply seeing words on a page.<\/p>\n
A Problem With Written Words, Not Eyes<\/p>\n
In the 19th century, doctors encountered people who could speak, write, and understand language normally, yet struggled to read. In the 1870s, German physician Adolf Kussmaul gave this puzzling condition an evocative name: Wortblindheit, or \u201cword blindness\u201d (Stollznow, 2026).<\/p>\n
However, the label was misleading. These people were not literally blind, and their eyesight was often perfectly normal. Their difficulty was with the written word. The mystery was how someone could see a word clearly yet be unable to make sense of it.<\/p>\n
Kussmaul\u2019s observations influenced Rudolf Berlin, a German ophthalmologist who studied patients struggling to read despite having normal vision. In 1877, Berlin coined a new term for the condition: dyslexia, from Greek roots meaning \u201cdifficulty with words.\u201d The new term shifted attention<\/a> away from blindness and toward the relationship between the brain and written language.<\/p>\n A Bright Boy Who Couldn\u2019t Read<\/p>\n Let\u2019s look at the case of Percy, a 14-year-old English boy described by physician William Pringle Morgan in 1896. Percy was, Morgan observed, \u201cbright and intelligent, quick at games, and in no way inferior to others of his age\u201d (Kirby & Snowling, 2022). Yet he could not learn to read. Percy\u2019s spelling was particularly inventive. He wrote \u201cscone\u201d for song, \u201cscojock\u201d for subject, \u201cwiehout\u201d for without, and even misspelled his own name as \u201cPrecy.\u201d<\/p>\n Morgan suspected that Percy\u2019s difficulty was a congenital defect. In modern terms, developmental dyslexia usually begins in childhood<\/a> and has a strong genetic component. It can run in families, although having a parent with dyslexia does not mean a child will necessarily develop it.<\/p>\n What stands out about Percy\u2019s story is how clearly Morgan distinguished his reading difficulty from his abilities in other areas. Percy\u2019s problem was not a lack of capacity or effort, but the specific challenge of making sense of written language. More than a century later, that distinction remains very important. Dyslexia is a difficulty with reading and language processing, not a measure of intelligence<\/a>.<\/p>\n When Reading Happens Differently<\/p>\n Today, researchers understand dyslexia as involving differences in how the brain processes written language, particularly the processing of sounds. One core difficulty is phonological awareness: recognizing, separating, and manipulating the sounds that make up words, and connecting those sounds with letters. That can make reading surprisingly effortful. A person with dyslexia may read slowly, misread words, struggle with spelling, or have difficulty distinguishing letters and sounds. Words may seem to blur together, and reading silently can be especially challenging.<\/p>\n But dyslexia does not mean that someone has trouble understanding language. In fact, some people with dyslexia find that they understand and remember information more easily when they hear it rather than read it. This is one reason audiobooks, text-to-speech software, and other tools can make such a difference.<\/p>\n