[MUSIC] Hello, my name is Turid Helland, I'm a professor emeritus from the University of Bergen in Norway. I'm a former teacher, a special language teacher, a speech and language therapist. And now, as a researcher, I am focusing on dyslexia and closely connected deficits like specific language impairment and math problems. In essence, this is a very difficult topic. It affects education and many individuals, irrespectable of their cognitive abilities. It is invisible and can thus be targeted by misunderstanding and disbeliefs. My four lessons will focus on, first of all, defining dyslexia, secondly, four different approaches to dyslexia, thirdly, dyslexia and comorbidities, and finally, what can a longitudinal study on dyslexia tell us? Questions have been raised if dyslexia exists irrespectively of languages, cultures, language typologies, orthographies, but recent cross-cultural studies have suggested that the answer is yes, but the symptoms vary in accordance with language typology and orthographies. As there is no consensus as how to define this impairment prevalence, in the literature, varies from 5 to 17, which is a big gap. But 4 to 9%, as suggested by Moll and collaborators seem more realistic. The upper panel you see here illustrates our present knowledge of the reading network of the brain. However, it's probably much more complex, which future studies certainly will show us. The lower panel suggest some of what we know about the language potentialities of the newborn. Any language can be learned, but after about a year, the brain of the child is adjusted to the linguistic characteristics of the home language. Studies of how the brain matures has given us insight into the importance of taking advantage of plasticity of the brain in young children when thinking of training. We know that about the age of six, more than 80% of the brain is grown and during that period the brain plasticity is optimal for training and learning. Speech is nature, reading is culture. Reading is hard because speech easy, it challenges the plasticity of the brain, I'm quoting Mattingly. The child has learned to comprehend and produce language and the step into literacy has to be taken by school entrance. But spoken language, into letters, words, and sentences, seems easy to most of us. But to some children, this process is not easy, the sounds and the letters will not cooperate, as you can see in this picture. Now, it's time to introduce my four friends and prototypes, Bob, John, Mary, and Mehn, who I made up from my numerous meetings with young and older children who struggle with literacy throughout their education. As far as I have experienced, their histories are recognized through concrete and school systems. Bob was given individual language training in a kindergarten due to his delayed language development. When he was ten, he still could not read or write words with more than three or four letters, he couldn't put them together, then he was diagnosed with dyslexia. John learned to read along with his fellow students, both in his first language, which was Norwegian, and his second language English, but his writings and pen and paper calculations were a mess, and the teachers could not read what he put on the paper. At age 12, he was diagnosed with dyslexia. Mary was a serious student, but this did not give her the credits in accordance with her ambitions. Finally, a teacher saw her struggle, the English language two teacher found that there was a big discrepancy between her oral or verbal and writing skills. So at age 15, her dyslexia was identified. Mehn came with his family to, let's say, Norway, when he was six and got all his schooling there. His slow progress in learning to read and write puzzled the teachers because he was very good at math. So the literacy problems were explained to him by being taught in a foreign language. Finally, when he was 17 and about to finish high school, he was diagnosed with dyslexia, a bit late. All four have been sitting in the classrooms, frustrated, afraid, angered, by not mastering what the others could do, for years in a situation they could not escape. So what are the symptoms of their dyslexia? Irrespectable of language or orthography, the key symptoms are slow and inaccurate reading and spelling. In writing, poor character formation, confusion of parts that make a word, use the wrong tone when they are reading out loud. The figure on the right panel shows reading scores from 2nd to 12th grade in school. All showed improvement over the years. The upper line is the typical group and the lower line is the persistent poor readers of, we could call them, the dyslexia group. The middle line shows result poor readers that is readers who showed early signs of impairment but who caught up with the typical readers. This figure illustrates that it can be difficult to differentiate between children with persistent and result problems earlier. The uncertainty is most of all rooted in how dyslexia has been defined. Although individual cases of dyslexia, word blindness was described over 100 years ago. It was not until 50 years ago definitions came up to be used in research primarily. But this also affected clinical work. The definition by the World Federation of Neurology from 1968 excluded children with an IQ lower than 85, which excluded Bob. Problems with reading had to be identified which excluded John. The uncertainties around Mehn's multicultural background excluded Mehn. Onlly Mary met the criteria with her discrepancy between the IQ scores and the low reading scores. According to the definition by the Orton Society from 1994, dyslexia is a language based impairment which would include Bob. The British Dyslexia Association have since then come up with several definitions, but which in essence are similar. As the other definitions it states that dyslexia is constitutional but apart from the two other definitions, it states that it affects literacy in a broader sense and that it is a multifactorial impairment. Still the three different definitions are being used and this is also reflected in research and in the clinic. So the situation is confusing. Ten different publications on dyslexia, ten different outcomes. This of course has to do with the lack of consensus as to definitions, but not only so. Dyslexia is more and more recognized as a multiple difficulty of multiple domains of impairment. It seems changed by age and development. So, how can we improve our understanding of dyslexia? Prominent researchers point to the need for longitudinal studies following children through the different literacy stages. To do so, we need some tools to help us. In 1995 Morton and Frith published a model for a structural approach to developmental disorders in general. According to the model any developmental order can be analyzed at that symptomatic level. What can be seen or observed behind the symptomatic level is the biological level. Genes, heredity, brain functions, which cannot be observed as easily or easily tested. The cognitive level is called the bridge connecting this symptomatic and the biological levels. The environmental level interacts with the three other levels and is detrimental to how each individual can cope with his or her problems. As different disorders have their own typical benchmarks, qualified testing, especially within the cognitive level can target the relevant cognitive factors of the disorder. Let us turn back to the definition of the British Dyslexia Association from 2007. It is a good definition because one it describes the symptoms of the disorder. The fact that development of literacy and longitudinal related language related skills. It describes cognitive benchmarks, phonological processing, rapid naming, working memory, processing speed and automaticity. It states that it is a constitutional impairment. Meaning that the affected individual is born with a disposition for dyslexia, which is at the biological level. Finally it is resistant to conventional teaching but can be mitigated by specific intervention from the environment. It is a good definition because one it is practice near meaning that it contains the impairments seen by the clinician. It is inclusive rather than exclusive. It's a good definition because it can help the researcher and the clinician to distinguish between the two types of weak readers we have seen in the figure. The result reader shows impairment within the symptomatic level only hence this is not a case of dyslexia. But what Frank Fritz has called false dyslexia. The persistent slow reader on the other hand will show impaired functions within several of the cognitive benchmarks. Hence true dyslexia can be identified. A last comment is needed since the focus here has been on cognitive factors. According to much and good research, there is a consensus that dyslexia is found in most variants within the IQ scale. Using the scale of the normal distribution, the person with dyslexia always score at the lower end on a test of literacy, but can be at the top end to other abilities such as music, arts, manual work et cetera. In other words dyslexia is identified independently of intelligence. So to sum up on how to define dyslexia studies point to a prevalence of I would say about between 5 and 10%, that dyslexia is seen across cultures and languages, that it affects or is affected by the language networking of the brain. That the young brain has largest plasticity than the older brain. And is thus more responsible to stimuli. That there are universal symptoms that we still have not reached consensus on how to define dyslexia, which we have demonstrated through three definitions that are still being used and that has consequences. Not only for how we understand research but also practice. There is not one factor that can identify dyslexia alone. But a multiple of factors. To sort out these factors, we have presented an evidence-based useful model and a definition that go hand-in-hand with this model.
