Surprising results in a new co-study from the Hebrew University of Jerusalem and French researchers show that the portion of the brain responsible for visual reading reacts the same whether the reader is sighted or blind.
The researchers found that brain imaging studies of blind people show activity in precisely the same part of the brain that lights up when people use vision to read. The study showed that regardless of sensory input, the brain doesn’t distinguish blind people reading Braille from sighted readers.
“To the best of our judgment, this provides the strongest support so far for the metamodal theory of brain function,” said Dr. Amir Amedi of the Hebrew University of Jerusalem, who spearheaded the research team.
Amedi’s team used functional magnetic resonance imaging (fMRI) to measure the neural activity in eight people who had been blind since birth while they read Braille words or nonsense Braille. Researchers focused in on a very specific part of the brain, known as the Visual Word Form Area, or VWFA, which shows peaks of activity when studying sighted readers.
Brain imaging studies of blind people as they read words in Braille show activity in precisely the same part of the brain that lights up when sighted readers read. The researchers said the findings challenge the textbook notion that the brain is divided up into regions that are specialized for processing information coming in via one sense or another.
“The brain is not a sensory machine, although it often looks like one; it is a task machine,” said Amedi, who is affiliated with the Institute for Medical Research Israel-Canada and the Edmond and Lily Safra Center for Brain Sciences at the Hebrew University. “A particular area fulfills a unique function, in this case reading, regardless of sensory input modality.”
The study was printed in the journal Current Biology.
Up next for the researchers is an examination of brain activity as people learn to read Braille for the first time. How does the brain change to process information in words? Is it instantaneous? This study hopes to shed more light on how the human brain tackles challenging tasks.