The Dyslexia Marker Test for Children: Development and Validation of a New Test

This article describes the development and psychometric properties of a new Dyslexia Marker Test for Children (Dysmate-C). The test was designed to identify Norwegian students who need special instructional attention. The computerized test includes measures of letter knowledge, phoneme awareness, rapid automatized naming, working memory, decoding, and spelling skills. Data were collected data from a sample of more than 1,100 students. Item response theory (IRT) was used for the psychometric evaluation, and principal component analysis for checking uni-dimensionality. IRT was further used to select and remove items, which significantly shortened the test battery without sacrificing reliability or discriminating ability. Cronbach’s alphas ranged between .84 and .95. Validity was established by examining how well the Dysmate-C identified students already diagnosed with dyslexia. Logistic regression and receiver operating characteristic (ROC) curve analyses indicated good to excellent accuracy in separating children with dyslexia from typical children (area under curve [AUC] = .92). The Dysmate-C meets the standards for reliability and validity. The use of regression-based norms, voice-over instructions, easy scoring procedures, accurate timing, and automatic computation of scores, make the test a useful tool. It may be used in as part screening procedure, and as part of a diagnostic assessment. Limitations and practical implications are discussed.

Genome-wide association analyses of individual differences in quantitatively assessed reading- and language-related skills in up to 34,000 people

The use of spoken and written language is a capacity that is unique to humans. Individual differences in reading- and language-related skills are influenced by genetic variation, with twin-based heritability estimates of 30-80%, depending on the trait. The relevant genetic architecture is complex, heterogeneous, and multifactorial, and yet to be investigated with well-powered studies. Here, we present a multicohort genome-wide association study (GWAS) of five traits assessed individually using psychometric measures: word reading, nonword reading, spelling, phoneme awareness, and nonword repetition, with total sample sizes ranging from 13,633 to 33,959 participants aged 5-26 years (12,411 to 27,180 for those with European ancestry, defined by principal component analyses). We identified a genome-wide significant association with word reading (rs11208009, p=1.098 x 10-8) independent of known loci associated with intelligence or educational attainment. All five reading-/language-related traits had robust SNP-heritability estimates (0.13-0.26), and genetic correlations between them were modest to high. Using genomic structural equation modelling, we found evidence for a shared genetic factor explaining the majority of variation in word and nonword reading, spelling, and phoneme awareness, which only partially overlapped with genetic variation contributing to nonword repetition, intelligence and educational attainment. A multivariate GWAS was performed to jointly analyse word and nonword reading, spelling, and phoneme awareness, maximizing power for follow-up investigation. Genetic correlation analysis of multivariate GWAS results with neuroimaging traits identified association with cortical surface area of the banks of the left superior temporal sulcus, a brain region with known links to processing of spoken and written language. Analysis of evolutionary annotations on the lineage that led to modern humans showed enriched heritability in regions depleted of Neanderthal variants. Together, these results provide new avenues for deciphering the biological underpinnings of these uniquely human traits.

The dimensionality of phonological awareness among Brazilian Portuguese-speaking children: a longitudinal study

Phonological awareness is one of the most important predictors of reading. However, there is still controversy concerning its dimensionality. This study evaluated the dimensionality of phonological awareness among Brazilian Portuguese-speaking children. A total of 212 children performed six phonological awareness tasks in the last year of kindergarten. Of those children, 177 performed the same tasks when they were in the first grade. The phonological awareness measures differed in both their cognitive demand (detection, blending, segmentation, and elision) and the phonological unit involved (rhyme, syllable, and phoneme). Confirmatory factor analyzes were employed to test several models of phonological awareness dimensionality. The results indicated that the best model was an oblique model of phonological units with two correlated latent factors: phonemic awareness and supraphonemic awareness. This model presented the best fit to the data both in kindergarten and in the first grade. In addition, supraphonemic awareness in the kindergarten predicted phoneme awareness in the first grade; however, phonemic awareness in the kindergarten did not predict supraphonemic awareness in the first grade. These results are compatible with phonological awareness developing from larger phonological units (e.g., syllables) to small phonological units (e.g., phonemes) and the reciprocal relationship between phonological awareness and reading. From a theoretical point of view, these results also suggest that phonological awareness is a one-dimensional construct that can be evaluated by tests employing different phonological units (e.g., syllables, rhymes, phonemes).

A network approach to dyslexia: Mapping the reading network

Research on the etiology of dyslexia typically uses an approach based on a single core deficit, failing to understand how variations in combinations of factors contribute to reading development and how this combination relates to intervention outcome. To fill this gap, this study explored links between 28 cognitive, environmental, and demographic variables related to dyslexia by employing a network analysis using a large clinical database of 1,257 elementary school children. We found two highly connected subparts in the network: one comprising reading fluency and accuracy measures, and one comprising intelligence-related measures. Interestingly, phoneme awareness was functionally related to the controlled and accurate processing of letter–speech sound mappings, whereas rapid automatized naming was more functionally related to the automated convergence of visual and speech information. We found evidence for the contribution of a variety of factors to (a)typical reading development, though associated with different aspects of the reading process. As such, our results contradict prevailing claims that dyslexia is caused by a single core deficit. This study shows how the network approach to psychopathology can be used to study complex interactions within the reading network and discusses future directions for more personalized interventions.

Neurocognitive Predictors of Response to Intervention With GraphoGame Rime

This study explores the neurocognitive predictors of response to intervention with GraphoGame Rime (GG Rime), an adaptive software game designed to aid the learning of English phonics. A cohort of 398 children (aged 6–7 years) who had participated in a recent randomised controlled trial (RCT) of GG Rime in the United Kingdom were studied. Half were randomly assigned to play GG Rime and the other half were assigned to Business As Usual (BAU). A series of pretests were given prior to the intervention to all participants, designed to measure phonological awareness skills, executive function (EF) skills and the ability to synchronise finger tapping to a rhythmic beat. Rhythmic synchronisation has been linked to reading readiness and early reading attainment, and is related to phonological awareness. Individual differences prior to the intervention in all three types of measure were significantly associated with progression through the game. Gender was also important for progression through the game, with boys progressing significantly further than girls. Vocabulary was not a predictor of progression through the game. Playing time, rhythmic synchronisation, phonological skills and EF skills did not differ by gender. Once playing time and non-verbal cognitive ability were controlled, phonological awareness, EF, rhythmic synchronisation and gender all remained significant predictors of progression through the game. In further analyses comparing these predictors, their interactions and controlling for the autoregressor of prior responsiveness to phonics instruction, phoneme awareness and EF skills were the strongest unique predictors. Analyses with the whole cohort (analysing BAU and GG children independently) showed that all neurocognitive measures contributed to progress in reading and spelling over the school year. We conclude that individual differences in phonological skills and EF skills predict which children will benefit most from computer assisted reading interventions like GG Rime. Further, boys respond better to this computerised intervention than girls. Accordingly, to be maximally beneficial to poor readers, the supplementary use of GG Rime in addition to ongoing classroom literacy instruction could be especially targeted to boys, but should be accompanied by a focus on developing both oral phonological awareness and EF skills.

Developmental Differences in the Availability of Cognitive Resources Supporting Rhyming and Dual Tasking

Purpose We investigated developmental differences in a dual task involving rhyming and tone judgment/decisions and the effects of varying cognitive demands on task performance. Method Participants were 7- to 11-year-olds, 12- to 15-year-olds, and adults between 18 and 40 years ( n = 19 per group). The rhyming task consisted of three stimuli categories (nonrhyme, rhyme, and replica), and the tone task stimuli were presented at short (100 ms) versus long (900 ms) stimulus onset asynchrony (SOA) from the onset of the rhyme task to vary cognitive demands. Response time (RT) and error data were analyzed using linear and binomial mixed-methods analysis, respectively. Results and Conclusions Adults did not show an SOA-based effect in rhyming RT, while the 12- to 15-year-olds showed the most effect (RT, long > short SOA). Response to the replica category was significantly faster than for the other categories in all age groups. A reverse SOA effect was evident in the tone task (RT, short > long SOA) in all age groups. The 7- to 11-year-olds showed twice the task switch cost effect in the tone task RT. Age grouping and phoneme awareness were significant predictors of performance in both tasks, and additionally, SOA was a significant predictor of performance in the secondary task. The findings have implications for (a) understanding maturational differences in rhyming and executive control for dual tasking and the cognitive mechanisms supporting such effects and (b) identifying variables contributing to the developmental differences.

Can a game application that boosts phonics knowledge in kindergarten advance 1st grade reading?

The Kalulu software is a tablet-based suite of phonics and reading-related lessons and minigames. In a previous intervention with a previous version of the software in 1st grade students, fluency and comprehension were boosted, but only when used in concert with reading instruction at the start of the year. Here, we asked whether a similar intervention would be more efficient if it started a year earlier, in kindergarten. Forty classes (1092= children) were randomized into playing Kalulu phonics or an active matched control game (Kalulu numbers) for the first half of the year. Those assignments were reversed in the second half of the year. Ten non-randomized business-as-usual classes also participated. In a cross- over effect, children who used the phonics version improved in letter naming, grapheme- phoneme matching and reading fluency, while those with the number version improved in number knowledge. In a longitudinal follow-up, intervention participants maintained an advantage in phoneme awareness and grapheme-phoneme matching at the start of 1st grade, but this advantage failed to translate into school literacy gains in the middle of 1st grade, and no longitudinal benefits were found for numbers. Those results improve our understanding of when and for how long to introduce phonics and question the possibility that a short-term intervention may address the complex challenges of long-term educational goals.

Comorbidity Between Math and Reading Problems: Is Phonological Processing a Mutual Factor?

There is a relationship between reading and math skills, as well as comorbidity between reading and math disorders. A mutual foundation for this comorbidity could be that the quality of phonological representations is important for both early reading and arithmetic. In this study, we examine this hypothesis in a sample traced longitudinally from preschool to first grade (N = 259). The results show that phonological awareness does not explain development in arithmetic, but that there is an indirect effect between phoneme awareness in preschool and arithmetic in first grade via phoneme awareness in first grade. This effect is, however, weak and restricted to verbal arithmetic and not arithmetic fluency. This finding is only partly in line with other studies, and a reason could be that this study more strongly controls for confounders and previous skills than other studies.