Since we have been discussing Synesthesia in the neuroscience seminar, I have become more interested in the connection between sensory input and brain processing. Recently I came across an article discussing some new research being conducted at Georgetown University Medical Center. Researchers found that when reading known words, individuals go though a process of image recognition rather than letter-processing. This finding may seem straightforward but it actually has implications in many different aspects of sensory processing.
Consider teaching a young child to read. You don’t say “hey you, memorize this picture of the word CAT, whenever you see that it means ‘cat’.” Instead, you encourage the child to sound out the word based on the sounds that correspond to certain letters: C-A-T. You might assume that once we become good readers and move on to more complex words, we just become faster at this process; our brain sees the word and almost automatically processes the letters and provides our conscious mind with the word.
The research at Georgetown indicates that this is not the case. Rather, once a word is learned, it is stored in the brain as an image that can be remembered. The brain area responsible for this function is the visual word form area, found on the left side of the visual cortex. The study tested this by providing subjects with novel “nonsense” words that needed to be learned. When reading words the subjects recognized the visual word form area was activated, but when presented with nonsense words that individuals had to read, the visual word form area was not activated. However, once the word was sufficiently learned, the area was activated.
Interestingly, the same location on the other side of the brain is the fusiform face area, which allows us to recognize faces. This led me to consider the possible connection of disabilities in reading (like dyslexia) and disorders like the inability to recognize faces. Both involve an individual with an ability to see individual components, but struggles to process the entire image. As Riesenhuber claims, his research helps to build evidence in support of alternative learning methods for people with reading disabilities that focuses on image recognition rather than learning to read through spelling words out.
Teber, Karen “After Learning New Words, Brain Stores Them as Pictures.” Georgetown University Medical Center. March 24, 2015. http://gumc.georgetown.edu/news/After-Learning-New-Words-Brain-Sees-Them-as-Pictures