Throughout much of the world, literacy is now a necessary skill needed to navigate and survive in an increasingly global society. Without being literate, one may find themselves unable to communicate effectively with the outside world, and ultimately be find themselves at a distinct disadvantage to their literate counterparts. This is why literacy has grown into becoming a humanitarian crisis for many nations, with literacy in at least one language now being taught in schools throughout the world. But how does the brain read? One explanation, which this blog will explore, is the Visual Word Form Area, which is an area of the brain capable of combining letters together in a meaningful fashion to allow the brain to read words.
While much work had been put into the study of the VWFA, the key missing piece was found, according to the article “How a Curious Condition Solved a Neuroscientific Mystery”, during a lesion study of a man under the alias of “Mike Brennan”, or M.B. M.B. one morning found he could not read his newspaper anymore, and so decided to go to the emergency room and see a neurologist, as he feared he had had a stroke. Doctors there discovered M.B. had a small stroke on his left occipitotemporal cortex, which caused the condition M.B. was suffering from, known as pure alexia, in which a patient cannot read but showed no other symptoms or deficiencies, such as being unable to recognize letters or symbols The exact location and the small size of the stroke confirmed that this area, which had previously been named the Visual Word Form Area, was intricate in the process of reading and, more importantly, forming words from the combination of letters. While this area of the brain was not discussed by Sophia A. Vinci-Booher either in her paper Neural substrates of sensorimotor processes: letter writing and letter perception or her talk at Loyola University Chicago, the paper does discuss an experiment performed in which an fMRI was performed on participants as they were shown letters and non-letters, where they were asked to identify the non-letters. Through this experiment, Vinci-Booher and her colleague were able to identify “premotor regions (including R-IFG and L-MFG), visual processing areas (including bilateral FuG), and a parietal region (L-IPS)” (Vinci-Booher and James, 2015, p.3) as areas of the brain which showed increased activity during letter perception. It is possible then that these brain regions and the Visual Word Form Area work together to allow the brain to read, with the Premotor Regions, Visual Processing Area, and Parietal Region working to identify letterform and distinguish between similar letters, and the Visual Word Form Area combining letters into a correct orientation to produces words.
(Inside the Letterbox: How Literacy Transforms the Human Brain)
While the Visual Word Form Area had been confirmed through the study of M.B., it was not always the case. Many previous studies, from teaching former Colombian Guerrilla fighters how to read, to analyzing the brain activity of illiterate versus literate adults was necessary in order to reach the point where M.B.’s story began relevant. First, beginning with teaching the Colombian Guerrillas to read, which was conducted by Dr. Manuel Carrerias it was found, through brain imaging throughout the time they were being taught to read, there was “enlarged grey matter in specific brain areas” (Barron, 2016) associated with reading, displaying that the brain was able to strengthen and mold certain areas when they were being utilized more. As well, in the study of illiterate adults versus literate adults, conducted by Dr. Stanislas Dehaene brain scans showed that the left inferior occipitotemporal cortex responded more sharply to writing and reading compared to other stimuli in literate adults, while illiterate adults responded relatively the same to all stimuli. This demonstrates that indeed as someone learns to read, the left inferior occipitotemporal cortex, which is the area in which the Visual Word Form Area is located, is “recycled from a general visual recognition center to a specialized word recognition center, at the expense of other tasks” (Barron, 2016), thereby strengthening the idea that the Visual Word Form Area is in fact the area that specializes and is necessary for the brain to read. Also, this idea of recycling of brain space to form a specialized task could as well explain a phenomenon Dr. Vinci-Booher spoke about during her presentation at Loyola University Chicago. Here, she talked about how, during visual and motor writing tests, areas of brain activity overlap occurred in a certain area for the adolescent groups, while overlap occurred in a different area of the brain for the adult group, although all groups were performing the same task. Through the work of Dr. Dehaene, this can be explained, as it is possible through experience and growth, the skills tested during the experiment compartmentalized in a certain area of the brain in adulthood after much practice and experience, while the skills were located in a more general and nonspecific area for the adolescents.
(Human Bulletin)
Overall, the study and subsequent discovery of the Visual Word Form Area of the brain had a great impact on the way neuroscientists today discuss how the brain reads. However, as shown previously, this is only a piece of the puzzle. The work of Dr. Vinci-Booher has clearly shown that other areas of the brain are necessary for letter perception, which most likely has some influence over the Visual Word Form Area and the its ability to read. The notion that brain areas can mold to specialize in one task and skills can move throughout the brain also opens the door to more brain areas becoming incorporated into our understanding of the connectivity and inner workings of the brain. While many more discoveries and breakthrough are sure to come, some very important groundwork has already been laid to answer the question, how does the brain read.
Works Cited:
Barron, Daniel. “How a Curious Condition Solved a Neuroscientific Mystery.” Scientific American Blog Network, Scientific American, 22 Aug. 2016, blogs.scientificamerican.com/mind-guest-blog/how-a-curious-condition-solved-a-neuroscientific-mystery/. Retrieved Oct. 10, 2017, from www.ScientificAmerican.com
Vinci-Booher S. (2017). Speech presented at Neuroscience Seminar, Loyola University Chicago.
Vinci-Booher S., James K. (2015). Neural substrates of sensorimotor processes: letter writing and letter perception. J Neurophysiol 115: 1–4, 2016. 22 July, 2015; doi:10.1152/jn.01042.2014.
Dehaene, Stanislas. “Figure 2.” Inside the Letterbox: How Literacy Transforms the Human Brain, 3 June 2015, dana.org/Cerebrum/2013/Inside_the_Letterbox__How_Literacy_Transforms_the_Human_Brain/#. Retrieved Oct. 12, 2017. [Image 1].
"How Does Reading Change The Brain." Human Bullitein. American Museum of Natural History, www.youtube.com/watch?v=AZ6HKCAhcAc. Retrieved Oct. 12, 2017. [Image 2].
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