Before journeying into the complex framework that underlies our ability to read and write, it is important to understand a number of key terms that will likely arise in the upcoming summaries.
is used herein to describe the feature possessed by neurons that allows them to forge new connections between existing points or systems in the brain. Of course, just as a road cannot be scored, paved, and painted overnight (often leading to infuriating standstills), construction of new neural “highways” does not occur without repetition and practice.
In addition to being capable of forging new connections, neurons can also take on new roles in a phenomenon known as neuronal recycling (Dehaene, 2010). So, for example, neurons that were originally used for object recognition may get repurposed or “recycled” for the process of letter recognition when we learn to read.
Evolutionarily, reading is a relatively new skill for humans, and the brain is not “programmed” for reading in the same way that it is for other skills such as face recognition and language. Instead, the brain must recycle neuronal pathways to develop reading skills. Brain imaging studies have helped us understand that specific regions and pathways are more likely to be recruited/recycled for the purpose of reading. Reading recruits many areas of the brain, as we process the words, sentences, vocabulary, emotions (and many other layers of language) embedded in text.
Relatedly, the specialization
of neurons or the formation of working groups
of neurons devoted to processing particular tasks allows for a child to read more efficiently over time. In fact, Maryanne Wolf’s research group has found that a child’s ability to name objects and, later, letters, predicts “how efficiently the rest of the reading circuit will develop over time” (Wolf et al., 2016). The fact that neurons or groups of neurons can become specialized at a task means that less neural “real estate” is required in order to accomplish the task. This reduction of area needed in the brain is known as progressive focalization
and importantly, frees other neurons to be “recycled” as discussed above. Moreover, higher-level processes (such as comprehension, in the case of reading) can also begin to take place as automaticity improves.
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