Foveal crowding in children with developmental dyslexia.

This study aims to compare the word decoding skills, phonological awareness (PA), rapid automatized naming (RAN) skills, and letter knowledge of first graders with developmental dyslexia (DD) and those who were typically developing (TD). Eighteen children with DD and eighteen TD children, matched by nonverbal intelligence and discourse ability, participated in the study. Word decoding of Korean language-based reading assessment(<xref ref-type="bibr" rid="B27">Pae <italic>et al.,</italic> 2015</xref>) was conducted. Phoneme-grapheme correspondent words were analyzed according to whether the word has meaning, whether the syllable has a final consonant, and the position of the grapheme in the syllable. Letter knowledge asked about the names and sounds of 12 consonants and 6 vowels. The children’s PA of word, syllable, body-coda, and phoneme blending was tested. Object and letter RAN was measured in seconds. The decoding difficulty of non-words was more noticeable in the DD group than in the TD one. The TD children read the syllable initial and syllable final position with 99% correctness. Children with DD read with 80% and 82% correctness, respectively. In addition, the DD group had more difficulty in decoding words with two patchims when compared with the TD one. The DD group read only 57% of words with two patchims correctly, while the TD one read 91% correctly. There were significant differences in body-coda PA, phoneme level PA, letter RAN, object RAN, and letter-sound knowledge between the two groups. This study confirms the existence of Korean developmental dyslexics, and the urgent need for the inclusion of a Korean-specific phonics approach in the education system.

Altered effective connectivity on rapid automatized naming deficits in Chinese children with developmental dyslexia: An rs-fMRI study with Ganger causality analysis

Two groups of pupils from special tract learning schools were randomly selected for this study. The first group (55 pupils) fulfilled the World Federation of Neurology (WFN) definition of developmental dyslexia (DD). The second group (retarded readers, RR) included 20 pupils with IQs between 80 and 90. A group of normal readers was randomly selected from the 5 school grades as a control group. This study showed that the performance IQ of the DD group was not only higher than the verbal IQ, but the DD group also had superior performance IQ compared to normal readers. In the arithmetic achievement test, both DD and RR groups had nearly similar total scores, which were significantly lower than that of the control group. None of the arithmetic subtests could differentiate between DD and RR groups. In linguistic achievement tests, only spontaneous writing and oral spelling could differentiate subjects with DD from the RR group.

PurposeDevelopmental dyslexia (DD) is commonly thought to arise from phonological impairments. However, an emerging perspective is that a more general procedural learning deficit, not specific to phonological processing, may underlie DD. The current study examined whether individuals with DD are capable of extracting statistical regularities across sequences of passively-experienced speech and non-speech sounds. Such statistical learning is believed to be domain-general, to draw upon procedural learning systems, and to relate to language outcomes.MethodDD and control groups were familiarized with a continuous stream of syllables or sine-wave tones, the ordering of which was defined by high or low transitional probabilities across adjacent stimulus pairs. Participants subsequently judged two three-stimulus test items with either high or low statistical coherence as the most similar to the sounds heard during familiarization.ResultsLike control participants, the DD group was sensitive to the transitional probability structure of the familiarization materials, as evidenced by above-chance performance. However, DD participants’ performance was significantly poorer than controls across linguistic and non-linguistic stimuli. Additionally, reading-related measures were significantly correlated with statistical learning performance of both speech and non-speech material.ConclusionsResults are discussed in light of procedural learning impairments among participants with DD.

Failure of resting-state frontal–occipital connectivity in linking visual perception with reading fluency in Chinese children with developmental dyslexia

ABSTRACTRecent work exploring syntax in developmental dyslexia (DD) has identified morphosyntactic deficits, striking parallelisms between children with DD and specific language impairment (SLI). The question remains open if the underlying causes for such deficits are related to difficulties in phonology, which is affected in DD, or to working memory, as has been previously reported for SLI. We focus on the production of third person accusative clitic pronouns (ACC3) and of homophonous definite determiners in French-speaking children with DD and SLI as well as typically developing (TD) controls. If syntactic complexity modulates performance of DD children, as has already been shown for SLI, we predict children with DD to perform significantly worse on ACC3 compared to definite determiners, which are homophonous but syntactically simpler. In addition, if impairment in ACC3 stems from phonology or working memory difficulties, we expect ACC3 performance in both clinical groups to relate to performance on non-word repetition or forward/backward digit spans. We studied 2 groups of 21 children and adolescents, with DD and SLI (7–15 years) and age-matched TD controls. Results reveal significant weaknesses with ACC3 in DD and SLI groups compared to TD controls, but no difficulty for homophonous definite determiners, confirming a deficit relating specifically to syntactic complexity. As for links to phonology and working memory, a single correlation emerged between ACC3 and the backward digit span in SLI, but not in DD, suggesting different underlying sources for syntactic deficits in these populations. Clinical implications of these results are discussed.

The human brain extracts statistical regularities from the surrounding environment in a process called statistical learning. Behavioural evidence suggests that developmental dyslexia affects statistical learning. However, surprisingly few studies have assessed how developmental dyslexia affects the neural processing underlying this type of learning. We used electroencephalography to explore the neural correlates of an important aspect of statistical learning – sensitivity to transitional probabilities – in individuals with developmental dyslexia. Adults diagnosed with developmental dyslexia (n = 17) and controls (n = 19) were exposed to a continuous stream of sound triplets. Every so often, a triplet ending had a low transitional probability given the triplet’s first two sounds (“statistical deviants”). Furthermore, every so often a triplet ending was presented from a deviant location (“acoustic deviants”). We examined mismatch negativity elicited by statistical deviants (sMMN), and MMN elicited by location deviants (i.e., acoustic changes). Acoustic deviants elicited a MMN which was larger in the control group than in the developmental dyslexia group. Statistical deviants elicited a small, yet significant, sMMN in the control group, but not in the developmental dyslexia group. However, the difference between the groups was not significant. Our findings indicate that the neural mechanisms underlying pre-attentive acoustic change detection and implicit statistical auditory learning are both affected in developmental dyslexia.

To study reading acuity in children and assess the reliability of its measurement using the Italian version of the MNREAD reading chart. One hundred sixteen children from grades 3 to 8 with normal near vision were tested at a pediatric eye care institution in northeastern Italy. Visual acuity was evaluated with Early Treatment Diabetic Retinopathy Study (ETDRS) charts and reading acuity with MNREAD charts. Examination with charts 1 and 2 by the same examiner in the same visit were used as test-retest measurements. Mean improvement of performance from grades 3 to 8 was approximately 1 line for ETDRS acuity and 1.5 sentences for reading acuity and critical print size. Mean maximum reading speed increased from 96 to 167 words/minute. Regression analysis showed that a stable reading speed was obtained throughout sentences of decreasing size up to the critical print size. Measurement error, expressed as 95% limits of agreement, was +/- 0.136 logarithm of the minimum angle of resolution (logMAR) and +/- 0.142 logMAR for ETDRS acuity and reading acuity, respectively. Critical print size had the lowest reliability (+/- 0.193 logMAR). Maximum reading speed limits of agreement were +/- 0.077 logarithm of words per minute (logWPM), or a 19% change in words per minute. There were no detectable effects of grade and refractive error on measurement errors. In children, MNREAD charts provide measurements of reading acuity as reliable as ETDRS chart measurements of distance acuity on a logMAR scale. They also provide highly reliable measurements of the maximum reading speed across all grades, independent of its noticeable increase.

Clinical relevance Myopia control is a prominent area of global research, with multifocal contact lenses identified as an effective intervention for adolescents. Background This study aims to evaluate the visual performance and vision-related quality of life (QoL) of myopic adolescents when corrected with pupil-optimised multifocal soft contact lenses (MFSCLs) versus single-vision contact lenses (SVCLs), with each participant serving as their own control. Methods Thirty-five myopic adolescents, habitually wearing SVCLs and fitted with pupil-optimised MFSCL with mid-addition power, were recruited. The assessment included distance visual acuity (DVA), near visual acuity (NVA), maximum reading speed (MRS), reading acuity (RA), contrast sensitivity (CS), and stereoacuity (SA) in photopic conditions for both types of lenses. Vision-related QoL was quantified twice for both lens types using the National Eye Institute Visual Function Questionnaire (NEI VFQ-42), covering 13 vision-specific domains. Results Comparisons of visual outcomes between MFSCLs and SVCLs for the same subjects revealed statistically significant differences in DVA (p = 0.010), NVA (p = 0.014), MRS (p = 0.044), and RA (p < 0.001), with SVCLs outperforming in DVA only. No significant difference in CS and SA was observed between the two lens types. According to the NEI VFQ-42, scores for clarity of vision, far vision, glare, and satisfaction with correction were higher with SVCLs, while the score for near vision was higher with MFSCLs. When fitted with MFSCLs, no significant correlations were found between pupil size and age of the patient with any visual examination parameters. However, there was a significant negative correlation between the DVA, NVA and the spherical equivalent of the lens. Conclusion MFSCLs with mid-add power significantly improve NVA, MRS, and RA, albeit with a reduction in DVA compared to SVCLs. While SVCLs were associated with better clarity of vision, far vision, and satisfaction with correction, MFSCLs offered superior performance in near vision tasks, according to the NEI VFQ-42 scores.

A different finding on the role of cerebro-cerebellar RSFC in reading skills among Chinese children with developmental dyslexia.

ABSTRACTVerbal fluency tasks, in which participants generate words during a set time, have been used in research and assessments of neurobiological disorders and impairments. Research on verbal fluency in dyslexia has shown impaired performance in semantic and letter fluency. However, studies report inconsistent results, and action fluency has not been examined in dyslexia. Current research has mainly examined verbal fluency in relation to executive functions, vocabulary, and phonological processing. The present study examined performance on letter, semantic, and action fluency in relation to reading ability in 42 students in higher education, of which 16 had developmental dyslexia and 26 had typical reading development. It was examined if verbal fluency can predict variance in reading ability when group, phonological awareness, and rapid automatized naming are controlled for. Results showed impaired verbal fluency in the developmental dyslexia group. Action fluency and group were significant predictors of reading ability, together explaining 73% of the variance, in a backward elimination regression analysis. The results point to a possible, unique connection between action fluency and reading ability; this connection is discussed based on their neurocognitive underpinnings.

The clinical interaction of Attention Deficit Disorder with Hyperactivity (ADD/HA) and Developmental Reading Disorder (DRD) is discussed. A treatment program that is particularly suited to children with ADD/HA and DRD is described. A recently completed study of the effects of methylphenidate on the reading achievement of ADD/HA children is described and selected results are presented to support the conclusions that: (a) special reading instruction can substantially improve achievement rates in children with ADD/HA and DRD, and (b) the degree to which methylphenidate reduces the behavioral symptoms of ADD/HA is a crucial factor in determining a child's response to DRD therapy.

Although a genetic component is known to have an important role in the etiology of developmental dyslexia (DD), we are far from understanding the molecular etiopathogenetic pathways. Reduced measures of neurobiological functioning related to reading (dis)ability, i.e. endophenotypes (EPs), are promising targets for gene finding and the elucidation of the underlying mechanisms. In a sample of 100 nuclear families with DD (229 offspring) and 83 unrelated typical readers, we tested whether a set of well-established, cognitive phenotypes related to DD [i.e. rapid auditory processing (RAP), rapid automatized naming (RAN), multisensory nonspatial attention and visual motion processing] fulfilled the criteria of the EP construct. Visual motion and RAP satisfied all testable criteria (i.e. they are heritable, associate with the disorder, co-segregate with the disorder within a family and represent reproducible measures) and are therefore solid EPs of DD. Multisensory nonspatial attention satisfied three of four criteria (i.e. it associates with the disorder, co-segregates with the disorder within a family and represents a reproducible measure) and is therefore a potential EP for DD. Rapid automatized naming is heritable but does not meet other criteria of the EP construct. We provide the first evidence of a methodologically and statistically sound approach for identifying EPs for DD to be exploited as a solid alternative basis to clinical phenotypes in neuroscience.

The aim of the study was to examine the role of phonological processing in people with and without dyslexia, who should have already mastered the skill of reading. We tested 98 high school students aged 16–18 years, including 49 with dyslexia and 49 without. The results indicate that the participants with dyslexia, as compared with participants without dyslexia, read single words and pseudowords less correctly and slower, which is consistent with literature on the subject. In addition, they scored significantly poorer in the phoneme blending, rapid automatic naming, and backward digit span task. In the criterion group, the relationship between phonological awareness and reading fluency was much stronger, and between rapid automatic naming and reading fluency slightly weaker than in the control group. This indicates a greater influence of long-term memory on reading in high school students without dyslexia.

Randomized clinical trials are needed to compare effectiveness and cost-effectiveness of different low-vision (LV) programs. To determine the value of adding LV rehabilitation with a therapist compared with LV services without intervention. A randomized clinical trial was conducted from September 27, 2010, to July 31, 2014, of 323 veterans with macular diseases and best-corrected distance visual acuity (BCDVAbetter-eye) of 20/50 to 20/200. Masked interviewers administered questionnaires by telephone before and after LV treatment. Using an intention-to-treat design, participants were randomized to receive LV devices with no therapy or LV devices with a rehabilitation therapist providing instruction and homework on the use of LV devices, eccentric viewing, and environmental modification. Visual ability was measured in dimensionless log odds units (logits) (0.14-logit change in visual ability corresponds to ability change expected from a 1-line change in visual acuity). Low-vision devices without therapy and LV devices with therapy. Comparison of changes (baseline to 4 months) in overall visual ability and in 4 functional domains (reading, visual information, visual motor, and mobility) estimated from responses to the Veterans Affairs Low Vision Visual Functioning Questionnaire (higher scores indicates more ability or less difficulty in performing activities), and comparison of MNREAD changes (baseline to end of treatment) in maximum reading speed, critical print size, and reading acuity (higher number indicates lower visual acuity). Of the 323 participants, 314 were male (97.2%); mean (SD) age, 80 (10.5) years. Basic LV was effective in improving visual ability. However, the LV rehabilitation group improved more in all visual function domains except mobility. Differences were 0.34-logit reading (95% CI, 0.0005 to 0.69; P = .05), 0.27-logit visual information (95% CI, 0.01 to 0.53; P = .04), 0.37-logit visual motor (95% CI, 0.08 to 0.66; P = .01), and 0.27-logit overall (95% CI, 0.06 to 0.49; P = .01). For MNREAD measures, there was more improvement in reading acuity (difference, -0.11 logMAR, 95% CI, -0.15 to -0.07; P < .001) and maximum reading speed (mean increase of 21.0 words/min; 95% CI, 6.4 to 35.5; P = .005), but not critical print size for the LV rehabilitation group (-0.06 logMAR; 95% CI, -0.12 to 0.002; P = .06). In stratified analyses, the LV rehabilitation group with BCDVAbetter-eye worse than 20/63 to 20/200 improved more in visual ability (reading, visual motor, and overall). Differences were 0.56-logit reading ability (95% CI, 0.08-1.04; P = .02), 0.40-logit visual motor (95% CI, 0.03-0.78; P = .04), 0.34-logit overall (95% CI, 0.06-0.62; P = .02). There was no significant difference between treatment groups for those with BCDVAbetter-eye of 20/50 to 20/63. Both basic LV alone and combined with LV rehabilitation were effective, but the added LV rehabilitation increased the effect only for patients with BCDVAbetter-eye worse than 20/63 to 20/200. Basic LV services may be sufficient for most LV patients with mild visual impairment. clinicaltrials.gov Identifier: NCT00958360.