Update: I’m experimenting with audio for some of my posts. If you’d like to listen to me reading this one aloud, click the play button:
Something went wrong in the teacher’s head one morning while she was taking attendance of her kindergarten class. She didn’t recognize any of the names on the page in front of her, and couldn’t even comprehend the individual letters. She rushed over to her lesson plans, and those, too, were cryptic.
A few days later the teacher, aged 40, would learn that a stroke had left her with a rare neurological condition: alexia without agraphia, more commonly called word blindness. People with this disorder can write words and understand spoken words. But they can’t read. This week, researchers Jason Cuomo, Murray Flaster, and José Biller of the Loyola University Medical Center published a fascinating description of this woman’s case in the medical journal Neurology.
More than a hundred years ago, a neurologist in France named Joseph Jules Dejerine described a case of alexia without agraphia for the first time. Dejerine’s patient, a businessman who liked to gamble and read music, lost his ability to read — both letters and musical notes — after having a stroke. Dejerine followed him for four years and observed that the man had no loss of intelligence: He continued to operate his booming business, listen to operas, and even play cards. He never learned to read, but he improvised by using his finger to trace the outline of letters on a page.
Dejerine’s patient is historically important because he was one of the first examples of a “disconnection syndrome,” according to a landmark paper published by esteemed neurologist Norman Geschwind in 1965. The man’s autopsy showed damage in the left occipital cortex, a region that processes vision, and in a part of the corpus callosum, a large bundle of nerve fibers that connects the brain’s left and right hemispheres. Dejerine hypothesized that the man’s word blindness came about because his intact right occipital cortex could not make connections to language areas of the brain.
The same thing happened in the teacher’s brain. After analyzing her MRI scans, doctors pinpointed damage in the left occipital cortex and the corpus callosum ‐ the very two regions affected in Dejerine’s patient.
The teacher, known as M.P., has something else in common with the older case. Without any prompting from her doctors, M.P. began using a finger-tracing method for reading. Here’s how her doctors describe it in their report:
To see this curious adaptation in practice is to witness the very unique and focal nature of her deficit. Given a word, M.P. will direct her attention to the first letter, which she is unable to recognize. She will then place her finger on the letter and begin to trace each letter of the alphabet over it, in order, until she recognizes that she has traced the letter she is looking at. “That is the letter M,” she declares, after tracing the previous 12 letters of the alphabet with her finger while deciphering a word in front of her. Three letters later, she is able to shorten this exercise with a guess: “This word is ‘mother,’” she announces proudly.
Perhaps most interesting, M.P. has not lost the emotions that her brain had previously associated with the sight of a word. The report gives two vivid examples. The first came when her doctors showed her written words for different foods. “When shown the word ‘dessert’ in writing, M.P. exclaimed, ‘Oooh, I like that!’” the researchers write. “When shown the word ‘asparagus’ moments later, however, her response was rather different. ‘I’m not doing this word! Something’s upsetting me about this word!’ she exclaims.”
The second example came from M.P.’s mother, whom M.P. was living with at the time. When shown two letters that had come in the mail, M.P. quickly gave one to her mother and put the other in her purse. She couldn’t read the names of the senders, but yet she felt some emotional connection with one of the names and not with the other.
M.P.’s stroke stole her livelihood, as she can no longer teach children how to read. But she is working, at the front desk of a local fitness center, and hopes to one day write a memoir of her story to raise money for stroke research.
If you’re in the mood for more neurological case studies, in 2012 Cuomo, Flaster, and Biller published another intriguing report of two people with the rare Bálint syndrome. These people can see objects, but can’t point to them in space and can’t see the full visual field surrounding them.