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Increasing evidence has shown visual attention span to be a factor, distinct from phonological skills, that explains single-word identification (pseudo-word/word reading) performance in dyslexia. Yet, little is known about how well visual attention span explains text comprehension. Observing reading comprehension in a sample of 105 high school students with dyslexia, we used a pathway analysis to examine the direct and indirect path between visual attention span and reading comprehension while controlling for other factors such as phonological awareness, letter identification, short-term memory, IQ and age. Integrating phonemic decoding efficiency skills in the analytic model, this study aimed to disentangle how visual attention span and phonological skills work together in reading comprehension for readers with dyslexia. We found visual attention span to have a significant direct effect on more difficult reading comprehension but not on an easier level. It also had a significant direct effect on pseudo-word identification but not on word identification. In addition, we found that visual attention span indirectly explains reading comprehension through pseudo-word reading and word reading skills. This study supports the hypothesis that at least part of the dyslexic profile can be explained by visual attention abilities. Copyright © 2016 John Wiley & Sons, Ltd., (Copyright © 2016 John Wiley & Sons, Ltd.)

The core cognitive difficulty in developmental dyslexia involves phonological processing, but adults and children with dyslexia also have sensory impairments. Impairments in basic auditory processing show particular links with phonological impairments, and recent studies with dyslexic children across languages reveal a relationship between auditory temporal processing and sensitivity to rhythmic timing and speech rhythm. As rhythm is explicit in music, musical training might have a beneficial effect on the auditory perception of acoustic cues to rhythm in dyslexia. Here we took advantage of the presence of musicians with and without dyslexia in musical conservatoires, comparing their auditory temporal processing abilities with those of dyslexic non-musicians matched for cognitive ability. Musicians with dyslexia showed equivalent auditory sensitivity to musicians without dyslexia and also showed equivalent rhythm perception. The data support the view that extensive rhythmic experience initiated during childhood (here in the form of music training) can affect basic auditory processing skills which are found to be deficient in individuals with dyslexia., (Copyright © 2014 John Wiley & Sons, Ltd.)

Impaired auditory sensitivity to amplitude rise time (ART) has been suggested to be a primary deficit in developmental dyslexia. The present study investigates whether impaired ART-sensitivity at a pre-reading age precedes and predicts later emerging reading problems in a sample of Dutch children. An oddball paradigm, with a deviant that differed from the standard stimulus in ART, was administered to 41-month-old children (30 genetically at-risk for developmental dyslexia and 14 controls) with concurrent EEG measurement. A second deviant that differed from the standard stimulus in frequency served as a control deviant. Grade two reading scores were used to divide the at-risks in a typical-reading and a dyslexic subgroup. We found that both ART- and frequency processing were related to later reading skill. We however also found that irrespective of reading level, the at-risks in general showed impaired basic auditory processing when compared to controls and that it was impossible to discriminate between the at-risk groups on basis of both auditory measures. A relatively higher quality of early expressive syntactic skills in the typical-reading at-risk group might indicate a protective factor against negative effects of impaired auditory processing on reading development. Based on these results we argue that ART- and frequency-processing measures, although they are related to reading skill, lack the power to be considered single-cause predictors of developmental dyslexia. More likely, they are genetically driven risk factors that may add to cumulative effects on processes that are critical for learning to read., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Potential links between the language and motor systems in the brain have long attracted the interest of developmental psychologists. In this paper, we investigate a link often observed (e.g., [Wolff, P.H., 2002. Timing precision and rhythm in developmental dyslexia. Reading and Writing, 15 (1), 179-206.] between motor tapping and written language skills. We measure rhythmic finger tapping (paced by a metronome beat versus unpaced) and motor dexterity, phonological and auditory processing in 10-year old children, some of whom had a diagnosis of developmental dyslexia. We report links between paced motor tapping, auditory rhythmic processing and written language development. Motor dexterity does not explain these relationships. In regression analyses, paced finger tapping explained unique variance in reading and spelling. An interpretation based on the importance of rhythmic timing for both motor skills and language development is proposed.

Twenty children (Grades 4 to 6) who met research criteria for dyslexia were randomly assigned to a treatment (attention training) or contact control (reading fluency training) group during their regular language arts block at a school that had emphasized multisensory, structured language treatment for reading disability. A university team provided either individual attention training (sustained, selective, alternating, and divided attention) or reading fluency training during the first 10 sessions and group composition instruction during the next 10 sessions. Analysis of variance evaluated the significance of Treatment x Session interactions from pretest to midtest (before composition instruction began) and midtest to posttest (when compositon instruction ends). Treatment x Time interactions were not significant between pretest and midtest, but the Treatment x Time interactions were significant from midtest to posttest for Wechsler Individual Achievement Test, Second Edition Written Composition and Delis-Kaplan Executive Function System Verbal Fluency (attention treatment group improved more over time). Individual children showed the same pattern as group results. For child dyslexics in upper elementary school, attention training did not transfer directly to improved composition but prior attention training led to faster improvement in composing and oral verbal fluency once composition instruction was introduced. Effective instruction for dyslexia may depend on the sequencing as well as the nature of instructional components and require specialized instruction for writing as well as reading.

In this article, we explore whether structural characteristics of the phonological lexicon affect serial recall in typically developing and dyslexic children. Recent work has emphasized the importance of long-term phonological representations in supporting short-term memory performance. This occurs via redintegration (reconstruction) processes, which show significant neighborhood density effects in adults. We assessed whether serial recall in children was affected by neighborhood density in word and nonword tasks. Furthermore, we compared dyslexic children with typically developing children of the same age or reading level. Dyslexic children are held to have impaired phonological representations of lexical items. These impaired representations may impair or prevent the use of long-term phonological representations to redintegrate short-term memory traces. We report significant rime neighborhood density effects for serial recall of both words and nonwords, for both dyslexic and typically developing children.

Dyslexia is a common, complex disorder, which is thought to have a genetic component. There have been numerous reports of linkage to several regions of the genome for dyslexia and continuous dyslexia-related phenotypes. We attempted to confirm linkage of continuous measures of (1) accuracy and efficiency of phonological decoding; and (2) accuracy of single word reading (WID) to regions on chromosomes 2p, 6p, 15q, and 18p, using 111 families with a total of 898 members. We used both single-marker and multipoint variance components linkage analysis and Markov Chain Monte Carlo (MCMC) joint segregation and linkage analysis for initial inspection of these regions. Positive results were followed with traditional parametric lod score analysis using a model estimated by MCMC segregation analysis. No positive linkage signals were found on chromosomes 2p, 6p, or 18p. Evidence of linkage of WID to chromosome 15q was found with both methods of analysis. The maximum single-marker parametric lod score of 2.34 was obtained at a distance of 3 cM from D15S143. Multipoint analyses localized the putative susceptibility gene to the interval between markers GATA50C03 and D15S143, which falls between a region implicated in a recent genome screen for attention-deficit/hyperactivity disorder, and DYX1C1, a candidate gene for dyslexia. This apparent multiplicity of linkage signals in the region for developmental disorders may be the result of errors in map and/or model specification obscuring the pleiotropic effect of a single gene on different phenotypes, or it may reflect the presence of multiple genes.

It is now well-established that there is a causal connection between children's phonological skills and their acquisition of reading and spelling. Here we study low-level auditory processes that may underpin the development of phonological representations in children. Dyslexic and control children were given a battery of phonological tasks, reading and spelling tasks and auditory processing tasks. Potential relations between deficits in dyslexic performance in the auditory processing tasks and phonological awareness were explored. It was found that individual differences in auditory tasks requiring amplitude envelope rise time processing explained significant variance in phonological processing. It is argued that developmentally, amplitude envelope cues may be primary in establishing well-specified phonological representations, as these cues should yield important rhythmic and syllable-level information about speech.

Recent research has suggested a novel link between deficits in the perception of cues relevant to speech rhythm (i.e., deficits in amplitude envelope rise time processing, or beat perception) and the phonological deficits seen in most dyslexic children. In this research, we investigated whether these beat perception deficits were specific to a stress-timed language, such as English, or whether they would generalize to languages with different rhythmic properties, such as French. Eighteen dyslexics, 18 reading level controls, and 20 chronological age controls were tested on a battery of phonological tasks, reading tasks and psychoacoustic tests. The results suggest that deficits in the perception of cues important for speech rhythm may be universal in developmental dyslexia., (Copyright 2004 Lippincott Williams and Wilkins)

In this study, we examined the neuroanatomy of dyslexic (14 males, four females) and control (19 males, 13 females) children in grades 4-6 from a family genetics study. The dyslexics had specific deficits in word reading relative to the population mean and verbal IQ, but did not have primary language or motor deficits. Measurements of the posterior temporal lobe, inferior frontal gyrus, cerebellum and whole brain were collected from MRI scans. The dyslexics exhibited significantly smaller right anterior lobes of the cerebellum, pars triangularis bilaterally, and brain volume. Measures of the right cerebellar anterior lobe and the left and right pars triangularis correctly classified 72% of the dyslexic subjects (94% of whom had a rapid automatic naming deficit) and 88% of the controls. The cerebellar anterior lobe and pars triangularis made significant contributions to the classification of subjects after controlling for brain volume. Correlational analyses showed that these neuroanatomical measurements were also significantly correlated with reading, spelling and language measures related to dyslexia. Age was not related to any anatomical variable. Results for the dyslexic children from the family genetics study are discussed with reference to dyslexic adults from a prior study, who were ascertained on the basis of a discrepancy between phonological coding and reading comprehension. The volume of the right anterior lobe of the cerebellum distinguished dyslexic from control participants in both studies. The cerebellum is one of the most consistent locations for structural differences between dyslexic and control participants in imaging studies. This study may be the first to show that anomalies in a cerebellar-frontal circuit are associated with rapid automatic naming and the double-deficit subtype of dyslexia.

A core difficulty in developmental dyslexia is the accurate specification and neural representation of speech. We argue that a likely perceptual cause of this difficulty is a deficit in the perceptual experience of rhythmic timing. Speech rhythm is one of the earliest cues used by infants to discriminate syllables and is determined principally by the acoustic structure of amplitude modulation at relatively low rates in the signal. We show significant differences between dyslexic and normally reading children, and between young early readers and normal developers, in amplitude envelope onset detection. We further show that individual differences in sensitivity to the shape of amplitude modulation account for 25% of the variance in reading and spelling acquisition even after controlling for individual differences in age, nonverbal IQ, and vocabulary. A possible causal explanation dependent on perceptual-center detection and the onset-rime representation of syllables is discussed.

Dyslexia is a common and complex behavioral disorder characterized by unexpected difficulty in learning to read. Psychometric measures used to assess dyslexia often evaluate overlapping processes or abilities. To identify subphenotypes amenable to model-based linkage analyses, we have used careful language phenotyping, familial aggregation analyses of single phenotype measures, and segregation analyses. In the current study, to identify covariates to use in future segregation analyses we examined six pairs of related measures selected from among the most promising candidates in the initial aggregation analyses whose aggregation patterns were most consistent with a genetic basis. For these reciprocal aggregation analyses each measure is evaluated with the paired measure as the covariate to obtain information about the interdependence of the paired measures on shared genetic factors. Six pairs of measures were evaluated: 1) accuracy and efficiency of phonological decoding; 2) phonological nonword memory and written spelling; 3) phonological decoding accuracy and written spelling; 4) inattention ratings and rapid automatized naming for switching letters and numerals (RAS); 5) inattention ratings and oral reading rate; and 6) RAS and oral reading rate. Results of these analyses provide evidence that there may be a genetic contribution to efficiency of phonological decoding in addition to the genetic contribution it shares with accuracy of phonological decoding, a genetic contribution to phonological nonword memory in addition to the genetic contribution it shares with written spelling, a genetic contribution to written spelling in addition to the genetic contribution it shares with accuracy of phonological decoding, and a genetic contribution to inattention ratings in addition to the genetic contribution it shares with either RAS or oral reading rate., (Copyright 2002 Wiley-Liss, Inc.)

The purpose of this study was to compare the efficacy of two auditory processing interventions for developmental dyslexia, one based on rhythm and one based on phonetic training. Thirty-three children with dyslexia participated and were assigned to one of three groups (a) a novel rhythmic processing intervention designed to highlight auditory rhythmic information in non-speech and speech stimuli; (b) a commercially-available phoneme discrimination intervention; and (c) a no-intervention control. The intervention lasted for 6 weeks. Both interventions yielded equivalent and significant gains on measures of phonological awareness (at both rhyme and phoneme levels), with large effect sizes at the phoneme level. Both programs had medium effect sizes on literacy outcome measures, although gains were non-significant when compared to the controls. The data suggest that rhythmic training has an important role to play in developing the phonological skills that are critical for efficient literacy acquisition. It is suggested that combining both prosodic/rhythmic and phonemic cues in auditory training programs may offer advantages for children with developmental dyslexia. This may be especially true for those who appear resistant to conventional phonics training methods.

Across languages, children with developmental dyslexia are known to have impaired lexical phonological representations. Here, we explore associations between learning new phonological representations, phonological awareness, and sensitivity to amplitude envelope onsets (rise time). We show that individual differences in learning novel phonological representations are related to individual differences in both rise time categorization and rise time discrimination when non-verbal IQ and short-term memory skills are controlled. This is consistent with the developmental claim that difficulties in the basic auditory processing of rise time cause difficulties in setting up the phonological lexicon from infancy, leading to impairments in phonological awareness.

Children with developmental dyslexia appear to be insensitive to basic auditory cues to speech rhythm and stress. For example, they experience difficulties in processing duration and amplitude envelope onset cues. Here we explored the sensitivity of adults with developmental dyslexia to the same cues. In addition, relations with expressive and receptive rhythm tasks, such as tempi recognition and manual tapping to a metronome, were explored. Our goal was to investigate whether the auditory deficits seen in dyslexia are specific to cues to speech rhythm and stress, or are part of a wider rhythmic awareness problem. A group of 19 undergraduate students with dyslexia were compared with 20 age- and ability-matched controls. The findings confirmed a relationship between auditory rhythm sensitivity and literacy in adults, as well as showing an association with metronome inter-tap-interval variability.

Recent theoretical advances in working memory guided analyses of cognitive measures in 122 children with dyslexia and their 200 affected biological parents in families with a multigenerational history of dyslexia. Both children and adults were most severely impaired, on average, in three working memory components- phonological word-form storage, time-sensitive phonological loop, and executive functions involving phonology. Structural equation modeling showed that, for children, first-order factors from the phonological, orthographic, and/or morphological word forms uniquely predicted 11 reading and writing outcomes but, for adults, a second-order factor (reflecting interrelationships among the three first-order word-form factors) was more likely to be significant in predicting the same reading and writing outcomes. Structural equation modeling of the three working memory component factors showed that the most consistent predictor of text-level reading and writing for both children and adults was the second-order word-form factor. Phonological loop and executive support could be modeled as separate factors in children but only as combined factors in adults. Executive support in children and combined phonological loop and executive support in adults contributed uniquely to oral reading but did not contribute uniquely to reading comprehension or written expression. For both children and adults, individual differences occurred as to which of the three working memory components or three word forms fell outside the normal range.

It is now well-established that there is a causal connection between children's phonological skills and their acquisition of reading and spelling. Here we study low-level auditory processes that may underpin the development of phonological representations in children. Dyslexic and control children were given a battery of phonological tasks, reading and spelling tasks and auditory processing tasks. Potential relations between deficits in dyslexic performance in the auditory processing tasks and phonological awareness were explored. It was found that individual differences in auditory tasks requiring amplitude envelope rise time processing explained significant variance in phonological processing. It is argued that developmentally, amplitude envelope cues may be primary in establishing well-specified phonological representations, as these cues should yield important rhythmic and syllable-level information about speech. (Contains 1 figure and 4 tables.)

The purpose of this study was to compare the efficacy of two auditory processing interventions for developmental dyslexia, one based on rhythm and one based on phonetic training. Thirty-three children with dyslexia participated and were assigned to one of three groups (a) a novel rhythmic processing intervention designed to highlight auditory rhythmic information in non-speech and speech stimuli; (b) a commercially-available phoneme discrimination intervention; and (c) a no-intervention control. The intervention lasted for 6 weeks. Both interventions yielded equivalent and significant gains on measures of phonological awareness (at both rhyme and phoneme levels), with large effect sizes at the phoneme level. Both programs had medium effect sizes on literacy outcome measures, although gains were non-significant when compared to the controls. The data suggest that rhythmic training has an important role to play in developing the phonological skills that are critical for efficient literacy acquisition. It is suggested that combining both prosodic/rhythmic and phonemic cues in auditory training programs may offer advantages for children with developmental dyslexia. This may be especially true for those who appear resistant to conventional phonics training methods. [ABSTRACT FROM AUTHOR]

Across languages, children with developmental dyslexia are known to have impaired lexical phonological representations. Here, we explore associations between learning new phonological representations, phonological awareness, and sensitivity to amplitude envelope onsets (rise time). We show that individual differences in learning novel phonological representations are related to individual differences in both rise time categorization and rise time discrimination when non-verbal IQ and short-term memory skills are controlled. This is consistent with the developmental claim that difficulties in the basic auditory processing of rise time cause difficulties in setting up the phonological lexicon from infancy, leading to impairments in phonological awareness. [ABSTRACT FROM AUTHOR]

Children with developmental dyslexia appear to be insensitive to basic auditory cues to speech rhythm and stress. For example, they experience difficulties in processing duration and amplitude envelope onset cues. Here we explored the sensitivity of adults with developmental dyslexia to the same cues. In addition, relations with expressive and receptive rhythm tasks, such as tempi recognition and manual tapping to a metronome, were explored. Our goal was to investigate whether the auditory deficits seen in dyslexia are specific to cues to speech rhythm and stress, or are part of a wider rhythmic awareness problem. A group of 19 undergraduate students with dyslexia were compared with 20 age- and ability-matched controls. The findings confirmed a relationship between auditory rhythm sensitivity and literacy in adults, as well as showing an association with metronome inter-tap-interval variability. [ABSTRACT FROM AUTHOR]

Recent theoretical advances in working memory guided analyses of cognitive measures in 122 children with dyslexia and their 200 affected biological parents in families with a multigenerational history of dyslexia. Both children and adults were most severely impaired, on average, in three working memory components— phonological word-form storage, time-sensitive phonological loop, and executive functions involving phonology. Structural equation modeling showed that, for children, first-order factors from the phonological, orthographic, and/or morphological word forms uniquely predicted 11 reading and writing outcomes but, for adults, a second-order factor (reflecting interrelationships among the three first-order word-form factors) was more likely to be significant in predicting the same reading and writing outcomes. Structural equation modeling of the three working memory component factors showed that the most consistent predictor of text-level reading and writing for both children and adults was the second-order word-form factor. Phonological loop and executive support could be modeled as separate factors in children but only as combined factors in adults. Executive support in children and combined phonological loop and executive support in adults contributed uniquely to oral reading but did not contribute uniquely to reading comprehension or written expression. For both children and adults, individual differences occurred as to which of the three working memory components or three word forms fell outside the normal range. [ABSTRACT FROM AUTHOR]