Letter reversals are common when a child is first learning how to read. To understand why, we need to investigate how our brains process spoken and written language. Spoken language is naturally picked up by using various language centers in the brain. The human brain was not designed to decode written language. This means we are using parts of our brain that are designed to perform entirely different tasks. One of the areas of the brain responsible for reading is the visual cortex. This part of the brain was designed for us to recognize things like objects and faces. For example, here are various pictures of chairs.
Despite each one of them looking quite different, we recognize each one of them as being a chair. We can group and identify them under one category because they share specific qualities. In this case, they all have a place to rest your bottom and your back. A child can use their sense of object constancy to accurately identify a rocking chair as a chair even if they have never seen one before. Now let us look at this concept in a different way:
Even though we are looking at the object from a different vantage point, we can still identify the object as a chair. The visual cortex gives us a sense of visual form constancy so we can still identify the object as a chair even if it is flipped upside down or backward. The visual cortex is wired to be able to identify an object no matter what changes it may have in its orientation or size in space.
Now here is where things get complicated. The rules of form constancy do not apply when learning letters and learning how to read. For example, a child is presented with the letter “b”. Later the same child is presented with the letter “d”. To a child who has mastered form constancy, they will look at both of those letters and think they are the same.
We now must explain to the child that the rules they have applied to every object in the past no longer applies with letters. The process of reading requires an overruling of the previously understood concept of object form constancy.
For even a smart child, each one of these letters is a bubble with a stick attached to it. Every child goes through the same process of rewiring an already understood concept of form constancy to understand that each one of these letters is a separate object. This process takes time for the child’s brain to rewire itself and embed the new concepts. Letter reversals should decrease as the child gains reading experience but can be expected until age seven. If letter reversals are persisting past age seven, there may be an underlying visual processing problem.
in literacy acquisition. Pegado F, Nakamura K and Hannagan T (2014).
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