Gary Stix in Scientific American:
Socrates famously railed against the evils of writing. The sage warned that it would “introduce forgetfulness into the soul of those who learn it: they will not practice using their memory because they will put their trust in writing.” He got a few things wrong. For one, people nurture Socrates’ memory because of all of the books written about him. But he also was off the mark in his musings about a forgetfulness of the soul. If anything, it appears that just the opposite holds: a study of hundreds of illiterate people living at the northern end of an island considered to be a world media capital roundly contradicts the father of Western philosophy. Evaluations of the elderly in the environs of Manhattan’s Washington Heights (the neighborhood immortalized by a Lin-Manuel Miranda musical) reveal that the very act of reading or writing—largely apart from any formal education—may help protect against the forgetfulness of dementia. “The people who were illiterate in the study developed dementia at an earlier age than people who were literate in the study,” says Jennifer J. Manly, senior author of the paper, which appeared on November 13 in Neurology.
Earlier studies trying to parse this topic had not been able to disentangle the role of reading and writing from schooling to determine whether literacy, by itself, could be a pivotal factor safeguarding people against dementia later in life. The researchers conducting the new study, who are mostly at Columbia University’s Vagelos College of Physicians and Surgeons, recruited 983 people with four years or less of schooling who were part of the renowned Washington Heights–Inwood Columbia Community Aging Project. Of that group, 238 were illiterate, which was determined by asking the participants point-blank, “Did you ever learn to read or write?”—followed by reading tests administered to a subsample. Even without much time in school, study subjects sometimes learned from other family members.
More here.