What happens in the brain when we read

Reading seems like a familiar and simple process, but in fact the brain does a complex job at it, engaging multiple areas, especially in the left hemisphere. Researchers at the Max Planck Institute for Cognitive and Brain Sciences conducted the largest meta-analysis covering 163 neuroscience studies. Their goal is to understand how the brain processes different types of text and why this is so important for health and social life.

Reading primarily activates the so-called “language areas” of the left hemisphere. Different areas of the left hemisphere are activated depending on the complexity of the material: one area responds to individual letters, another to words and pseudowords, and another to sentences and whole texts. For example, reading letters activates only a small area in the occipital cortex, while reading sentences engages the temporal and frontal lobes.

The researchers also found interesting differences between reading to oneself and reading aloud. When reading aloud, the areas responsible for movement and sound are active – this helps to coordinate speech and pronunciation. And when reading silently, the areas responsible for attention, control and inner speech are more important.

In addition, it was observed that when participants simply decided whether a word was real or fictional (so-called lexical decision tasks), the brain worked differently than it did during full-blown reading. These “lexical decisions” activated more areas in both hemispheres, especially in the frontal and insular cortices, while reading real words to oneself more often involved the temporal lobes and cerebellum.

The authors hope their review will help to further understand how literacy develops and why some people have difficulty reading. This could be a step toward developing more accurate and effective ways to help children with dyslexia and other disorders.