Turning Dyslexia Around with Neuroplasticity

Neuroplasticity or brain plasticity refers to the brain’s ability to change in response to learning. Learn how neuroplasticity, together with cognitive training, reading intervention, and proper learning principles, holds the answer to healing dyslexia.

What is neuroplasticity?

Neuroplasticity is one of the most extraordinary discoveries of the 20th century. It showed that our brains are not fixed once we grow up.

New brain cells are constantly being born and dying, new connections form and the internal structures of the existing synapses change. When a person becomes skilled in a specific domain, the brain areas involved in that skill grow. Neuroplasticity allows brain cells to adapt to injury and disease and change their activities in response to new situations or environmental changes.

The brain cannot change

For centuries, it was proclaimed that the brain could not change, let alone improve. People were told that when something was wrong with their brain, it could not be fixed; each person was born with a certain number of brain cells, and if any of them were injured, there was no way to reverse the damage.  The brain was seen as a complicated machine with fixed limits on memory, processing speed, and intelligence.

Today, we know the brain can change its structure and function, thereby increasing its learning capacity. If certain “parts” fail, other parts can sometimes take over. Plasticity exists from the cradle to the grave.

Neuro stands for “neuron,” the nerve cells in our brains and nervous systems. Plastic stands for “changeable, malleable, modifiable.” Scientists initially hesitated to use the term “neuroplasticity” in their work, and their colleagues criticized them for advocating a fanciful idea. However, they persisted and gradually overturned the belief in the unchangeable brain.

One daring scientist was James Hinshelwood, today considered the father of the study of dyslexia. Hinshelwood believed the brain to be plastic and used the word brain plasticity in his classic book, Congenital Word-blindness, published in 1917.

Hinshelwood considered dyslexia (at the time called word-blindness) to be treatable through personal and systematic instruction. Not only did he have hope for children with developmental dyslexia but also for people who acquired dyslexia later in life due to disease or brain damage. Hinshelwood believed the brain could be re-educated so that the corresponding centre on the opposite side of the brain would take over the functions of the defective cerebral area, and he detailed case studies of his patients who had done so.

Unfortunately, in the decades to follow, most scientists continued to maintain that the brain cannot change. They believed that if a part of the brain got damaged due to an injury or if a person was born with a mental condition, nothing could be done. This belief left little hope for people with dyslexia!

Brain plasticity is discovered

A significant study published in 1998 established that the human brain can create new brain cells. The study challenged the widely accepted belief that the human brain was a fixed system unable to generate new brain cells.

Further research showed that the brain is flexible and adaptable, also known as “plastic.” In a classic experiment from 2000, researchers compared the brains of London taxi drivers with those of non-taxi drivers, and in 2006, they also compared them with the brains of bus drivers. These two studies demonstrated that the brain can grow.

The studies found that London taxi drivers had larger posterior hippocampi than regular people and London bus drivers. The reason is that taxi drivers need to navigate through different routes around the city, while bus drivers follow a limited, fixed set of routes. Additionally, the more years of navigation experience a taxi driver had, the larger their hippocampal grey matter volume.

Similar findings of environmentally driven plasticity have been reported in other groups, including musicians, jugglers, and bilinguals. For example, professional musicians have more grey matter in certain brain areas the longer they practise and play. The same is true of early bilinguals.

A study led by UCL found that professional foot painters develop ‘hand-like’ maps of their toes in their brains. Skeide and team (2016) discovered that when adults learn to read for the first time, changes occur not only in the outer layer of the brain (cortex) but also in deep brain structures like the thalamus and brainstem. This study observed illiterate Indian women who learned to read and write over six months.

It is now believed that a brain can rewire itself after an injury. The healthy parts of a damaged brain can be trained to take over the functions of the damaged tissue. Hinshelwood expressed this idea in 1917, which is now supported by various studies.

The brains of people with dyslexia

Already in the late 19th century, Berlin, Morgan, and Hinshelwood linked dyslexia to brain functioning or brain lesions. In the 1980s and 90s, autopsy studies of individuals with known dyslexia histories appeared to support these long-standing beliefs.

As technology advanced, neuroscience increasingly contributed to dyslexia research. Studies have confirmed that people with dyslexia have distinct brain differences in structure and function compared to typical readers.

The most consistent finding concerns the left occipitotemporal cortex (shown in yellow), which includes the so-called visual word form area (VWFA), which is critical for reading. In skilled adult readers, this area groups the letters of words into visual units, allowing the reader to recognise words without having to scan the individual letters.

Another part of the brain involved in reading is the left inferior parietal lobe (shown in red). It helps with analysing words, converting letters to sounds, and processing both the sounds and meanings of words.

Both the VWFA and the parietal lobe may be impaired in students with dyslexia, which can lead to overactivation in other parts of the reading system (shown in green). When the VWFA is affected, children may read slowly and lack fluency. When the parietal lobe is affected, students will have trouble sounding out new words and may be limited to reading familiar words and guessing at unfamiliar ones.

In contrast, researchers at the University of Cambridge found no specific brain areas that cause learning disabilities like dyslexia. Instead, they discovered that children’s brains are organised around hubs, just like an efficient traffic system or social network. Children with well-connected brain hubs had no cognitive difficulties or specific cognitive difficulties, such as poor listening skills. On the other hand, children with poorly connected hubs had widespread and severe cognitive problems, just like a train station with few or poor connections.

It is not clear whether brain differences cause dyslexia or are a result of it. For example, Krafnick and team (2014) concluded that the brain differences found in the left-hemisphere language-processing areas seem to be a result of reading experiences rather than a cause of dyslexia.

Reduced plasticity in the dyslexic brain

So far, things seem simple and straightforward: the brain can change, so let us use neuroplasticity — which underpins the ability to learn new things — to heal dyslexia. Unfortunately, there is a snag. Research conducted by neuroscientists at MIT found that the brain’s ability to change is reduced in individuals with dyslexia.

The MIT team used MRI scans to study the brains of young adults with and without dyslexia as they did different tasks. In the first part of the study, the participants listened to a series of words read by either a single speaker or four different speakers.

In people without dyslexia, parts of the brain involved in language showed neural adaption (change) after hearing words said by the same person but not when different people said the words. However, people with dyslexia showed much less adaptation when hearing words said by a single person.

Next, subjects were asked to look at the same or different words, pictures of the same or different objects, and pictures of the same or different faces. The researchers found that in people with dyslexia, the brain regions responsible for interpreting words, objects, and faces showed significantly reduced adaptation compared to controls when the same stimuli were repeated multiple times.

Because adaptation is also decreased for the non-linguistic categories of visual objects and faces, the researchers concluded that dysfunction of neural adaptation is not about reading per se but a broad difference in perceptual learning.

In their final experiment, the researchers tested first and Grade 2-students with and without dyslexia. They found the same disparity in neural adaptation.

What does it mean?

What does the MIT team’s research mean for people with dyslexia? Does it suggest that memorisation and rote learning are ineffective learning strategies for dyslexia? Does it imply that dyslexia cannot be remedied? Were Clark and Gosnell correct when they stated that “dyslexia is like alcoholism … it can never be cured” (1982, pp. 55-56). Or is there hope? Was James Hinshelwood correct in believing that dyslexia can be turned around?

Once thought of as a rigid system, we now know that the brain is plastic. In fact, it is a powerhouse. It has enabled humans to reach the moon, developed the silicon chip that can perform billions of calculations per second, created traffic lights that manage millions of people daily, and even found ways to examine its own inner workings. Is this fantastic organ able to heal learning obstacles like dyslexia despite apparent brain differences?

While waiting for the answer in Part 2, visit our testimonial section and experience how Edublox training and tutoring help turn dyslexia and other learning difficulties around.

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