1.1.3 The brain structure

Scientists have found that the brains of people with dyslexia work a bit differently from those of typical readers (Norton, Beach and Gabrieli, 2015). In most people, the brain’s reading network is mainly on the left side, which gets stronger as we learn to read. In a dyslexic reader, there are fewer activations (hypoactivations) in the left temporal, parietal, and fusiform regions.

Building on this research, Kuhl et al. (2020) have made other discoveries. They found unusual folding patterns in specific areas. These areas are important for reading and processing sounds. Interestingly, these brain differences can be spotted even before a child learns to read!

Some findings involve various microscopic anomalies in the actual organisation of brain cells (Galaburda et al., 1985). Studies of brain cells show that people with dyslexia have some cells that are slightly out of place and layers of cells that aren’t as orderly. These differences are mostly found in the left side of the brain, which handles language. These ’misplaced’ cells (called ectopias) often have more connections to other brain areas, which might explain why people with dyslexia can be super creative.

Think back now to Week 1, and the early definition of dyslexia relating to ‘word blindness’. It’s time to revisit that idea with a consideration of visual-spatial awareness.

Revisiting visual-spatial awareness

Boys often exhibit greater visual-spatial awareness than girls, but this visual-spatial awareness does not prohibit the development of visual-perceptual difficulties linked to dyslexia.

Many dyslexic individuals report visual symptoms like letters and words appearing to move or blur, difficulties with small, crowded print, and visual discomfort such as glare.

Figure 2 Examples of visual disturbances experienced by some people with dyslexia

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This is a diagram demonstrating visual disturbances. There are two columns of text. One column’s text gives the impression that the words are swirling, moving around and overlapping. The other column’s text is blurred, with some words seeming distinguishable if hard to read, and other bits being completely unrecognisable as coherent text.

Figure 2 Examples of visual disturbances experienced by some people with dyslexia

Research highlights the role of the visual magnocellular system (Stein and Walsh, 1997; Stein, 2022), which is crucial for controlling eye movements and visual attention. Dyslexic readers often struggle with processing rapid visual information, affecting their ability to sequence letters correctly (Stein, 2022).

To help manage these visual challenges, studies suggest encouraging children to play action video games, which improve visual timing. Using colour filters, such as yellow or blue, can also aid in visual processing by stimulating the magnocellular cells (Stein, 2022). Therefore, one recommendation is printing on coloured paper, and using overlays in different formats. It’s important to remember though that this isn’t a ‘one size fits all’ solution and thus, finding the optimal colour and shade will take some trial and error.

Visual-spatial awareness can influence how dyslexic individuals process information, but many visual symptoms – like blurring or shimmering text – may be due to underlying eye health issues. According to the British Dyslexia Association (BDA), these should be assessed by a qualified optometrist. While coloured overlays may offer relief, they should not replace a full professional eye examination, as they don’t address the root causes of visual discomfort (British Dyslexia Association, n.d.)

Continuing with the structure of the brain, another theory involves the cerebellum, a brain structure essential for motor coordination and cognitive development. The cerebellum plays a significant role in the automatisation of skills, such as rote learning (i.e., learning facts ‘off by heart’, like multiplication tables) and phonological processing. A deficit in cerebellar function could explain various dyslexic features, including rapid sensory processing issues.

Understanding these brain characteristics and their impact on dyslexia can lead to better identification and support for individuals with this condition.