Given that humans only mastered written communication a few thousand years ago, it seems unlikely that our brains would have had enough time to evolve new mechanisms specifically for reading and writing. In spite of this, it has been known for many years that a particular brain region called the visual word form area (VWFA) exists in the brains of literate people, and reacts only to the sight of written letters and words. Now, a new study in the journal Nature Neuroscience indicates that even before we learn to read, a part of our brain is specifically primed for this precise task.
The cerebral cortex of the human brain consists of dozens of regions, each of which performs a particular function. The VWFA is one such region, but only exists in people who have learned to read – unlike the left fusiform face area (lFFA), which recognizes faces and exists even in illiterate children.
While these regions arise in roughly the same place in all brains, their exact location can differ slightly from person to person. Yet by examining the brain connectivity of young children before they learned to read, the study authors were able to pinpoint exactly where their VWFAs would form once they became literate a few years later. This suggests that the brain’s ability to learn to read is rooted in its inherent connectivity.
The researchers began by scanning the brains of a group of five-year-olds, noting that while they already displayed clear lFFAs that reacted to the presence of faces, no part of the brain was yet able to distinguish between faces and letters. Three years later, when participants had become literate, the scientists scanned their brains again, discovering that they had now developed VWFAs that responded specifically to seeing words and letters, but not faces.
By then returning to the earlier scans and looking at the “connectivity footprint” of a part of the cortex called the left occipitotemporal anatomical parcel – meaning the way that it communicated with other parts of the brain – the researchers were able to figure out exactly which group of neurons would go on to form the VWFA at age eight.
In other words, the connectivity profile of a small part of the five-year-old brains is specifically designed to be able to learn to read, even before that child knows his or her ABCs.
Study co-author Zeynep Saygin said in a statement that “it’s really powerful to be able to predict functional development three years ahead of time,” as it could allow doctors to identify certain neurological problems even before they arise.