Researchers discovered a previously-unrecognized fiber bundle in the brain that is believed to be involved in visual processes.
The lost brain highway, dubbed the vertical occipital fasciculus, was discovered when researchers we're looking at dozens of brain scans in an unrelated study, Washington University reported.
"It was this massive bundle of fibers, visible in every brain I examined," said Jason Yeatman, a research scientist at the University of Washington's Institute for Learning & Brain Sciences. "It seemed unlikely that I was the first to have noticed this structure; however, as far as I could tell, it was absent from the literature and from all major neuroanatomy textbooks."
When the researchers went through old brain atlases they found one written by Carl Wernicke from the turn of the 20th century that depicted the structure; it was seen published under a number of names such as "Wernicke's perpendicular fasciculus," "perpendicular occipital fasciculus of Wernicke," and "stratum profundum convexitatis." The findings may have been discarded because they contradictedTheodor Meynert, who beleived that brain connections could only travel in between the front and the back of the brain, as opposed to up and down.
To make their findings the researchers used an MRI measure called diffusion-weighted imaging to measure the size of the pathway and see where in the brain it went. After looking at 37 brains the researchers determined the vertical occipital fasciculus was located in the occipital lobe (part of the visualization process) and had fibers that spread out into connecting regions.
"We believe that signals carried by the VOF play a role in many perceptual processes, from recognizing a friend's face to rapidly reading a page of text," Yeatman said.
In their study the researchers also provided an algorithm that can be used by other scientists to measure the properties of brain pathways in the future.
"To support reproducible research, our lab makes a strong effort to share software and data," said Brian Wandell, senior author of the paper and a psychology professor at Stanford. "We believe this is a powerful way to ensure that our findings can be both checked and used in labs around the world."
The findings were published Nov. 17 by the Proceedings of the National Academy of Sciences.
