Dyslexia is a reading disability defined as a neurodevelopmental disorder with a likely genetic basis (Snowling, 2013). Behavioural studies have shown that difficulty in phonological processing (mapping sounds onto letters) is the core deficit of dyslexia (Maisog, Einbinder, Flowers, Turkeltaub & Eden, 2008). Such a deficit has been found to effect processing speed, fluency of reading and spelling ability (Snowling, 2013). In the past 20 years, neuroimaging studies have gained insight into the neural basis of dyslexia, which has enabled a more of a comprehensive understanding of the disorder within education (Johnson, 2015). This essay will therefore critically evaluate the role neuroscience has in the education of children with dyslexia. Firstly, this essay will discuss that neuroimaging research into the neural basis of dyslexia has provided proof that dyslexia is a neurological disorder. The essay will suggest that if teachers should be made aware of these findings they could have a greater understanding of the disorder and the strategies they can use to support dyslexic children in their education. The essay will then critically discuss that neuroimaging findings can also help explain behavioural symptoms of dyslexia. Following on, the essay will highlight neuroimaging findings that illustrate that, due to dysfunction of normal reading areas, children with dyslexia employ more distributed and inefficient neural pathway when reading. The essay will then go on to discuss how the observed inefficient nature of the abnormal reading pathways employed by dyslexic children highlights the importance of focusing intervention on improving efficiency in reading. Next, this essay will discuss how neuroimaging is able to that show improved reading ability after an intervention is associated with rehabilitating typical brain areas for reading as well as further strengthening of their developed compensating areas. Finally, the essay will show that neuroscience can identify children who will later go on to developing dyslexia. In turn, this could lead to early intervention before school which eliminates the effects of dyslexia before they show and the negative emotions associated with it. Overall, the main argument of this essay is that neuroscience has a crucial role in the education of children with dyslexia.
Firstly, neuroscience provides scientific proof that dyslexia is a real neurological cognition. For example, functional magnetic resonance imaging (fMRI) studies have shown that typical readers recruit different neural pathways to dyslexic readers. fMRI is a non-invasive brain imaging technique that evaluates and maps brain activity (Huettel, Song & McCarthy, 2004). Maisog, Einbinder, Flowers, Turkeltaub and Eden (2008) carried out two meta-analyses, one from studies that highlighted regions in which typical readers show greater activation than dyslexic readers and one from studies that highlighted regions in which dyslexic readers showed greater activation than typical readers. All studies used fMRI to compare the brain activity of typical and dyslexic readers during a common linguistic task assessing the phonological process. Overall, the most consistent finding was that dyslexic readers appear to underutilise their left temporoparietal and occipitotemporal areas compared to typical readers (Maisog et al., 2008). Conversely, dyslexic readers seemed to show greater activation in the right temporal and frontal lobes, specifically the right inferior frontal gyri (IFG). This different pattern of brain activation seen in the brains of dyslexic readers is thought to signify compensatory mechanisms (Hoeft et al., 2007). Thus, neuroscience has been able to illustrate the neural basis for dyslexia, referred to as the neural signature for dyslexia (Shaywitz et al., 2002). In turn, neuroscience has scientifically proven that dyslexia is a neurological condition which indeed makes it more tangible for educators.
After years of teachers not understanding behaviours of children with dyslexia, not believing them, thinking they are dumb, an understanding of the neural basis for dyslexia can promote a more comprehensive understanding of the neurological disorder. A study by Harter (1999) into the perceptions of school support of 25 students with dyslexia found that the majority believed that teachers lacked understanding of their disability. Dommett, Devonshire, Plateau, Westwell and Greenfield (2011) designed and ran an effective six-month long collaboration project between neuroscientists and teachers. The project included a selection of workshops on topics previously agreed on by the two groups whereby one was on the neuroscience of dyslexia and reading difficulties. The workshop presented the characteristic deficits of dyslexia, research into the neural basis for dyslexia as well as the possible treatment options. Quantitative feedback showed that 89% of teacher’s found the workshop on dyslexia to be challenging but accessible. In addition, qualitative feedback was that it ‘offered a scientific explanation on why pupils work differently’ (Dommett et al., 2011, p. 385). Ultimately it is the teachers who remediate the effect of dyslexia, therefore, a programme like this should be made widely available for teachers. It would aid their understanding of why children with dyslexia have different reading behaviours and can then provide various strategies to improve their reading. Therefore, neuroscience can play a role in promoting a comprehensive understanding of dyslexia for teachers which, in turn, will positively affect the education of children with dyslexia.
Neuroimaging findings can also aid the explanation of behavioural symptoms of dyslexia. For example, rapid automatised naming (RAN) tasks are used to test an individual’s capability to automatically and accurately retrieve labels for letters or numbers. Performance on RAN tasks governs reading fluency and processing speed (Norton & Wolf, 2012). Christodoulou et al. (2011) carried out a fMRI study on typical and dyslexic adult readers using a RAN task. During fMRI scanning, a screen with 50 letters or numbers arranged in five rows of ten items was presented to the participants. Participants were instructed to silently name each item as quickly as possible and then press a key to indicate their completion of a line. Due to reading fluency difficulties being a characteristic of dyslexia (Maisog et al., 2008), as expected, dyslexic readers completed fewer lines and took longer on each. fMRI showed that typical readers had greater activity in posterior areas in the bilateral (both sides of the bran) parietal and occipital regions more than dyslexic readers. Whereas, adults with dyslexia displayed more distributed activity in a variety of bilateral temporal and motor areas. Thus, it appears that fluency difficulties occur due to dyslexic readers employing a more distributed network as their compensatory mechanism. Again, such findings can help teachers understanding why children with dyslexia display different reading behaviour. However, fMRI is only correlational therefore neuroscience cannot conclude that difficulty in reading fluency is determined by the less efficient, compensatory circuit the dyslexic reader employed. Nevertheless, neuroscience has vividly illustrated that different areas are activated in dyslexic brains to compensate for dysfunction to normal brain areas and that such compensatory mechanisms represent a less efficient route.
Neuroscience also guides what interventions should contain to help children with dyslexia improve their reading ability. In typical readers, the visual word form area (VWFA), an area which is associated with visual word processing and situated in the left occipitotemporal area, has been found to be associated with reading fluency (Dehaene et al., 2001). During reading, a hierarchical relationship between the VWFA, the working memory system and the core language system has been established for typical readers (Makuuchi & Friederici, 2013). These areas are connected by a white matter fiber bundle in the brain, the arcuate fasciculus (Makuuchi and Friederici, 2013). Van der Mark et al. (2011) carried out a study using functional connectivity MRI to evaluate the connectivity between these areas in dyslexic children during a reading task. Results showed that for dyslexic readers, the connection between the VWFA and the core language areas was absent. This absence of direct connectivity may be what leads dyslexic readers to employ less efficient compensatory mechanisms to read, as seen in the RAN task (Christodoulou et al., 2011). Therefore, potential intervention for improving efficiency should focus on supporting dyslexic readers to access words faster. For example, interventions using word priming strategies could improve efficiency in reading for dyslexic children (Johnston, 2015). Word priming strategies typically involve presenting words or pictures that are phonologically or semantically associated with a target word. Johnston (2015) investigated the effect of picture and work priming on the reaction times of five dyslexic children during word recognition tasks. For all participants, Johnston (2015) found that that picture priming helped reading target words more efficiently (i.e., faster reaction times). Therefore, by neuroimaging highlighting that dyslexic children employ less efficient pathways during reading, this raises awareness that improving efficiency should a key part of their intervention.
Furthermore, neuroimaging is able to reveal the brain plasticity associated with phonological based intervention for dyslexia. Phonologically based reading interventions comprise of explicit and methodical instruction in phonological awareness and decoding strategies (Gabrieli, 2009). Decoding is the ability to determine the sound (phonology) of a word from letters. Decoding strategies are vital because relating sounds to letters is how one learns to read (Blischak, 1994). Shaywitz et al. (2004) used fMRI to investigate the effects of a phonological intervention on the brain organisation and reading fluency of children aged 6 to 9 with dyslexia. They found that children who received phonological intervention for a year saw significant improvements in their reading fluency. Furthermore, they displayed increased activation in the left occipitotemporal brain system, the brain area typically associated with reading (Maisog et al., 2008). This highlights that, by rehabilitating brain function in areas normally associated with reading, phonological intervention improves reading ability by ‘correcting’ the abnormal brains of children with dyslexia.
However, perceiving the brains of dyslexic individuals as abnormal and trying to develop the ideal brain activation could be oppressing compensating strategies that they have successfully developed. As shown earlier, increased activation in the right IFG has been found to be a compensatory mechanism for dyslexic children during reading (Maisog et al., 2008). Hoeft et al. (2011) carried out longitudinal research whereby at the beginning of the study, neuroimaging was carried out on children with and without dyslexia, along with a standardised assessment of reading ability. During fMRI, participants undertook a word rhyme judgment task. The test involved making rhyming judgements on a pair of presented words designed to initiate phonological analysis. Reading ability was then further assessed two and a half years on whereby dyslexic children who showed greater activation in the right IFG during a rhyme-judgement task showed greater reading improvement. Typical readers did not show this pattern. Therefore as children with dyslexia can still improve their reading ability by recruiting areas not typically associated with reading, endeavouring to develop the ideal brain activation ignores successful compensating strategies they have developed (Hoeft, et al., 2011). However, alongside increased activation in brain areas typically associated with reading, Shaywitz et al. (2004) also reported an increased activation in the right IFG after successful intervention. Therefore, by revealing the brain plasticity involved, neuroimaging has highlighted that successful interventions improve reading ability by not just ‘correcting’ the brains of dyslexic individuals but also further strengthening their compensating areas they have developed. In turn, neuroscience shows that interventions allow children with dyslexia to flourish in education and value their neural circuits developed.
Finally, neuroscience can also play role in early identification of individuals who will go on to developing dyslexia. For example, Molfese (2000) carried out a longitudinal study on 48 children using auditory event-related potentials (ERPs). ERP is a non-invasive technique to measure changes in electrical activity to displayed stimuli (Luck, 2014). In Molfese’s (2000) study, ERP measured brain responses to repeated speech and non-speech sounds in infants of just 36 hours of birth, and then in successive years near their birthday. At aged eight, all the children were assessed on standardised tests measuring their intelligence and linguistic ability. Molfese (2000) found that the ERP measures recorded at birth categorised with 81.25% accuracy the normal, poor and dyslexic readers at aged eight. Therefore as neuroscience can successfully identify those who will develop dyslexia early in life, interventions could be carried out before reading problems later emerge at school. Currently, identification of dyslexia is established via behavioural measures when children are 9 or 10 years old after the child has begun to display reading difficulties (Molfese, 2000). As children grow up and go through cognitive and linguistic development they become less cognitively flexible and therefore have a reduced ability to learn new skills (Witelson, & Swallow, 1987). Therefore, by identifying dyslexia earlier, interventions can be carried out before school which increases the chances of improving reading skills. Once at school, dyslexic individuals will not be at a disadvantage to their peers and hence can flourish in other aspects of education. Therefore it is clear that earlier identification of dyslexia by neuroscience methods could play a crucial role in a dyslexic child’s education. Hopefully, in the future, such measures could be implicated in a routine procedure for diagnosing dyslexia.
However, while early identification can positively affect child’s academia, it is possible that it could negatively their emotional well-being. For example, dyslexic students consider a label of dyslexia to be associated with stupidity (Harter, 1999). In turn, it comes as no surprise that dyslexia has been found to negatively affect the self-esteem of those diagnosed with it (Guilli, Mallory & Ramirez, 2005). Early identification of children that will develop dyslexia could make them feel abnormal and stupid, even before they show any reading problems. However, by remediating the child’s later emerging deficit before school, once at school they are no different to their peers. Ultimately, by being able to identify dyslexic individuals early, neuroscience can be the gateway to eliminate dyslexia and the negative emotions associated with it, instead of just trying to reduce their impact with compensatory strategies at school.
In conclusion, this essay has shown this neuroscience clearly has a role in the education of children with dyslexia. This essay has shown this by discussing neuroimaging studies that have uncovered the neural signature for dyslexia, proving dyslexia is a neurological disorder. Furthermore, presenting such findings to teachers can promote a comprehensive understanding of the disorder which, in turn, will positively affect the education of children with dyslexia. Furthermore, neuroimaging has shown that the compensatory mechanisms employed when reading in dyslexic children are more distributed and less efficient, potentially due to connectivity failure between important language areas. Such insight brings attention to the significance of improving the efficiency of reading for dyslexic children in intervention. Furthermore, neuroimaging has shown that successful phonological based intervention for dyslexic children rehabilitate normal brain areas and further strengthen compensating areas then have developed. Therefore, the neural circuits of children with dyslexia are valued and dyslexic children are able to flourish, not be educationally oppressed. Finally, neuroscience methods can identify children who will develop dyslexia before school meaning intervention can be implemented earlier. This could benefit a dyslexic child’s educational achievement and emotional well-being. Hopefully in the future, carrying out early ERP measures on new-borns will be a routine procedure for diagnosing dyslexia as the benefits of the education of the child are substantial.