The brain as a 'task machine'

Feb 17, 2011

The portion of the brain responsible for visual reading doesn't require vision at all, according to a new study published online on February 17 in Current Biology. 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 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 researchers say.

"The brain is not a sensory machine, although it often looks like one; it is a task machine," said Amir Amedi of The Hebrew University of Jerusalem. "A brain area can fulfill a unique function, in this case reading, regardless of what form the takes."

Unlike other tasks that the brain performs, reading is a recent invention, about 5400 years old. Braille has been in use for less than 200 years. "That's not enough time for evolution to have shaped a brain module dedicated to reading," Amedi explained.

Nevertheless, study coauthor Laurent Cohen showed previously in sighted readers that a very specific part of the brain, known as the visual word form area or VWFA for short, has been co-opted for this purpose. But no one knew what might happen in the brains of blind people who learn to read even though they've had no visual experience at all.

In the new study, Amedi's team used to measure in eight people who had been blind since birth while they read Braille words or nonsense Braille. If the brain were organized around processing sensory information, one might expect that Braille reading would depend on regions dedicated to processing tactile information, Amedi explained. If instead the brain is task oriented, you'd expect to find the peak of activity across the entire brain in the VWFA, right where it occurs in sighted readers, and that is exactly what the researchers found.

Further comparison of brain activity in blind and sighted readers showed that the patterns in the VWFA were indistinguishable between the two groups.

"The main functional properties of the VWFA as identified in the sighted are present as well in the blind, are thus independent of the sensory modality of reading, and even more surprisingly do not require any visual experience," the researchers wrote. "To the best of our judgment, this provides the strongest support so far for the metamodal theory [of brain function]," which suggests that brain regions are defined by the tasks they perform. "Hence, the VWFA should also be referred to as the tactile word form area, or more generally as the (metamodal) word form area."

The researchers suggest that the VWFA is a multisensory integration area that binds simple features into more elaborate shape descriptions, making it ideal for the relatively new task of reading.

"Its specific anatomical location and its strong connectivity to language areas enable it to bridge high-level perceptual word representation and language-related components of reading," they wrote. "It is therefore the most suitable region to be taken over during reading acquisition, even when reading is acquired via touch without prior ."

Amedi said the researchers plan to examine brain activity as people learn to read Braille for the first time, to find out how rapidly this takeover happens. "How does the change to process information in words?" he asked. "Is it instantaneous?"

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User comments : 9

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kevinrtrs
1 / 5 (13) Feb 17, 2011
Unlike other tasks that the brain performs, reading is a recent invention, about 5400 years old.

Just how exactly does the researcher know this? Did anyone have access to the age modules linked to reading in the brain?

We were created with full capability to understand and transcribe languages, no evolution required.

The researcher's time estimate fits more or less into the creation paradigm but one needs to question just how he got to know that information if he is not a creationist.

As for the research itself - this VWFA would be borne out in dreams - since one does not have any visual stimulation from the eyes yet one is able to "see" things. It might be interesting to find out if the visions in dreamland also take place in the same area.
gmurphy
4.3 / 5 (4) Feb 17, 2011
@kevinrtrs, you disgust me. Please find another website where other people share your beliefs. I really enjoyed reading this article only to have it spoiled by your demented comment. Please, please, please, just go away.
jselin
4.3 / 5 (6) Feb 17, 2011
Kevin,

Cuneiform is traced back as early as ~3400BC... its ~2000AD now. The tablets were probably radiocarbon dated (or other isotopes) but I have a feeling you don't hold much stock in that. Honest question not intended as a jab- If the bible provides absolute truth why are you seeking answers anywhere else?
Terrible_Bohr
3.7 / 5 (3) Feb 17, 2011
You live in dreamland, Kevintrs. Care to undergo an MRI to find out?
pauljpease
4 / 5 (4) Feb 17, 2011
Unlike other tasks that the brain performs, reading is a recent invention, about 5400 years old.

Just how exactly does the researcher know this?


Because no one has found any evidence of written language before ~5400 years ago. No written language = no reading.
Terrible_Bohr
5 / 5 (2) Feb 17, 2011
Appearantly, RayCherry is deeply offended by anyone posting a comment on this article.
SkiSci
not rated yet Feb 18, 2011
Reading was invented to understand the bible
frajo
5 / 5 (1) Feb 19, 2011
Reading was invented to understand the bible
Reading was invented (along with writing) many millennia before the Bible was written.
Skeptic_Heretic
5 / 5 (1) Feb 19, 2011
We were created with full capability to understand and transcribe languages, no evolution required.
My German is rusty, so bear with me.

Kevin, sie sind so lacherlich.

Can you read that? I guess not. Maybe it's the fact the site won't take the umlat over the a, or perhaps your God didn't make you properly. After all, you're saying we should all be able to read and understand that phrase.

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