Search

We review the evolution of the conceptualisation of dyslexia and along with it the current, 21st century definition of dyslexia. Our starting point is the seminal report by Pringle Morgan in 1896, followed by early 20th century reports by Hinshelwood, and continuing with concepts of brain injury and minimal brain dysfunctions then to the emergence of 'learning disability' in the mid-20th century. Within this historical framework we note the emergence and scientific validation of an 'unexpected' model culminating in the first definition of dyslexia in U.S. federal law in late 2018 and in recent U.S. federal civil rights law. We next address the issue of whether dyslexia is 'real' by showing how advances in non-invasive functional brain imaging have led to a replicated, robust neural signature for dyslexia. We close by illustrating how science has informed policy, emphasising the focus on evidence-based practices beginning with the report of the National Reading Panel and including the creation of the What Works Clearinghouse. Early screening for dyslexia represents another important policy accomplishment with dyslexia laws now passed in over 30 states. Evidence-based effective interventions for dyslexia, including free, public charter schools specialised for dyslexic children exemplify the most recent policy initiative. [ABSTRACT FROM AUTHOR]

Response to Intervention (RTI) models of diagnosis and intervention are being implemented rapidly throughout the schools. The purposes of invoking an RTI model for disabilities in the schools clearly are laudable, yet close examination reveals an unappreciated paucity of empirical support for RTI and an overly optimistic view of its practical, problematic issues. Models are being put into practice without adequate research and logistical support and neglect the potential negative long-term impact on students with disabilities. Many implementation problems exist: (a) the vagaries of critical details of the model in practice; (b) the lack of consideration of bright struggling readers; (c) the relativeness, contextual, situation dependent nature of who is identified; (d) the worrisome shortcomings of the RTI process as a means of diagnosis or determination of a disability; and (e) the apparent lack of student-based data to guide effective choice of approaches and components of intervention. Practiced as a model of prevention, the authors agree with the concept of RTI. As the authors witness its application to disability determination sans the benefit of a reliable and valid empirical basis, the potential benefits to some children with disabilities remain an unproven hypothesis while the potential detriment to some children with disabilities remains a very real possibility. [ABSTRACT FROM AUTHOR]

J. M. Fletcher and S. Vaughn (2009) describe recent changes to federal laws governing special education eligibility for specific learning disabilities (LDs) focusing on what is commonly known as response to intervention (RTI). The article appears to be a selective review of empirical support for RTI and a consequently overly optimistic view of many practical issues surrounding the implementation of RTI models that neglects the potential negative long-term impact on the range of students with and without an LD. These include (a) the lack of a firm evidence base reflected in vagaries and ambiguity of the critical details of the model in practice; (b) the worrisome shortcomings of the RTI process as a means of diagnosis or determination of a disability; (c) the contextual, situation-dependent nature of who is identified; (d) the seeming lack of consideration of bright struggling readers in the RTI process; and (e) the apparent lack of student-based data to guide the most effective choice of approaches to, and specific components of, intervention. [ABSTRACT FROM AUTHOR]

Extraordinary progress in functional brain imaging, primarily advances in functional magnetic resonance imaging, now allows scientists to understand the neural systems serving reading and how these systems differ in dyslexic readers. Scientists now speak of the neural signature of dyslexia, a singular achievement that for the first time has made what was previously a hidden disability, now visible. Paralleling this achievement in understanding the neurobiology of dyslexia, progress in the identification and treatment of dyslexia now offers the hope of identifying children at risk for dyslexia at a very young age and providing evidence-based, effective interventions. Despite these advances, for many dyslexic readers, becoming a skilled, automatic reader remains elusive, in great part because though children with dyslexia can be taught to decode words, teaching children to read fluently and automatically represents the next frontier in research on dyslexia. We suggest that to break through this “fluency” barrier, investigators will need to reexamine the more than 20-year-old central dogma in reading research: the generation of the phonological code from print is modular, that is, automatic and not attention demanding, and not requiring any other cognitive process. Recent findings now present a competing view: other cognitive processes are involved in reading, particularly attentional mechanisms, and that disruption of these attentional mechanisms play a causal role in reading difficulties. Recognition of the role of attentional mechanisms in reading now offer potentially new strategies for interventions in dyslexia. In particular, the use of pharmacotherapeutic agents affecting attentional mechanisms not only may provide a window into the neurochemical mechanisms underlying dyslexia but also may offer a potential adjunct treatment for teaching dyslexic readers to read fluently and automatically. Preliminary studies suggest that agents traditionally used to treat disorders of attention, particularly attention-deficit/hyperactivity disorder, may prove to be an effective adjunct to improving reading in dyslexic students. [ABSTRACT FROM PUBLISHER]

The past two decades have witnessed an explosion in our understanding of dyslexia (or specific reading disability), the most common and most carefully studied of the learning disabilities. We first review the core concepts of dyslexia: its definition, prevalence, and developmental course. Next we examine the cognitive model of dyslexia, especially the phonological theory, and review empiric data suggesting genetic and neurobiological influences on the development of dyslexia. With the scientific underpinnings of dyslexia serving as a foundation, we turn our attention to evidence-based approaches to diagnosis and treatment, including interventions and accommodations. Teaching reading represents a major focus. We first review those reading interventions effective in early grades, and then review interventions for older students. To date the preponderance of intervention studies have focused on word-level reading; newer studies are beginning to examine reading interventions that have gone beyond word reading to affect reading fluency and reading comprehension. The article concludes with a discussion of the critical role of accommodations for dyslexic students and the recent neurobiological evidence supporting the need for such accommodations. [ABSTRACT FROM AUTHOR]

Within the last two decades, evidence from many laboratories has converged to indicate the cognitive basis for dyslexia: Dyslexia is a disorder within the language system and, more specifically, within a particular subcomponent of that system, phonological processing. Converging evidence from a number of laboratories using functional brain imaging indicates that there is a disruption of left-hemisphere posterior neural systems in child and adult dyslexic readers when they perform reading tasks. The discovery of a disruption in the neural systems serving reading has significant implications for the acceptance of dyslexia as a valid disorder—a necessary condition for its identification and treatment. Brain-imaging findings provide, for the first time, convincing, irrefutable evidence that what has been considered a hidden disability is “real,” and these findings have practical implications for the provision of accommodations, a critical component of management for older children and young adults attending postsecondary and graduate programs. The utilization of advances in neuroscience to inform educational policy and practices provides an exciting example of translational science being used for the public good. [ABSTRACT FROM AUTHOR]

Converging evidence from a number of lines of investigation indicates that dyslexia represents a disorder within the language system and more specifically within a particular subcomponent of that system, phonological processing. Recent advances in imaging technology, particularly the development of functional magnetic resonance imaging, provide evidence of a neurobiological signature for dyslexia, specifically a disruption of two left hemisphere posterior brain systems, one parieto-temporal, the other occipito-temporal, with compensatory engagement of anterior systems around the inferior frontal gyrus and a posterior (right occipito-temporal) system. Furthermore, good evidence indicates a computational role for the left occipito-temporal system: the development of fluent (automatic) reading. The brain systems for reading are malleable and their disruption in dyslexic children may be remediated by provision of an evidence-based, effective reading intervention. In addition, functional magnetic resonance imaging studies of young adults with reading difficulties followed prospectively and longitudinally from age 5 through their mid twenties suggests that there may be two types of reading difficulties, one primarily on a genetic basis, the other, and far more common, reflecting environmental influences. These studies offer the promise for more precise identification and effective management of dyslexia in children, adolescents and adults. [Copyright &y& Elsevier]

: BackgroundA range of neurobiological investigations shows a failure of left hemisphere posterior brain systems to function properly during reading in children and adults with reading disabilities. Such evidence of a disruption in the normal reading pathways provides a neurobiological target for reading interventions. In this study, we hypothesized that the provision of an evidence-based, phonologically mediated reading intervention would improve reading fluency and the development of the fast-paced occipitotemporal systems serving skilled reading.: MethodsFunctional magnetic resonance imaging was used to study the effects of a phonologically based reading intervention on brain organization and reading fluency in 77 children aged 6.1–9.4 years (49 with reading disability and 28 control subjects). Children comprised three experimental groups: experimental intervention (n = 37), community intervention (n = 12), and community control subjects (n = 28).: ResultsImmediately after the year-long intervention, children taught with the experimental intervention had made significant gains in reading fluency and demonstrated increased activation in left hemisphere regions, including the inferior frontal gyrus and the middle temporal gyrus; 1 year after the experimental intervention had ended these children were activating bilateral inferior frontal gyri and left superior temporal and occipitotemporal regions.: ConclusionsThese data indicate that the nature of the remedial educational intervention is critical to successful outcomes in children with reading disabilities and that the use of an evidence-based phonologic reading intervention facilitates the development of those fast-paced neural systems that underlie skilled reading. [Copyright &y& Elsevier]

: BackgroundA range of neurobiological investigations shows a failure of left hemisphere posterior brain systems to function properly during reading. Such evidence of a disruption in the normal reading pathways provides a neurobiological target for reading interventions. In this study, we hypothesized that the provision of an evidence-based, phonologically mediated reading intervention would improve reading fluency and the development of the fast-paced occipitotemporal systems serving skilled reading.: MethodsFunctional magnetic resonance imaging was used to study the effects of a phonologically based reading intervention on brain organization and reading fluency in 77 children aged 6.1–9.4 years (49 with reading disability and 28 control subjects). Children comprised three experimental groups: experimental intervention (n = 37), community intervention (n = 12), and community control subjects (n = 28).: ResultsImmediately after the year-long intervention, children taught with the experimental intervention had made significant gains in reading fluency and demonstrated increased activation in left hemisphere regions, including the inferior frontal gyrus and the middle temporal gyrus; 1 year after the experimental intervention had ended these children were activating bilateral inferior frontal gyri and left superior temporal and occipitotemporal regions.: ConclusionsThese data indicate that the nature of the remedial educational intervention is critical to successful outcomes in children with reading disabilities and that the use of an evidence-based phonologic reading intervention facilitates the development of those fast-paced neural systems that underlie skilled reading. [Copyright &y& Elsevier]

This paper elaborates on components of a working definition of developmental dyslexia. It follows the general format of a paper published in the periodical Annals of Dyslexia in 1995, which elaborated on a working definition proposed in 1994. The current definition agreed on by the work group updates and expands on the working definition from 1994. Dyslexia is a specific learning disability that is neurobiological in origin. It is characterized by difficulties with accurate and fluent word recognition and by poor spelling and decoding abilities.

: BackgroundThis study examined whether and how two groups of young adults who were poor readers as children (a relatively compensated group and a group with persistent reading difficulties) differed from nonimpaired readers and if there were any factors distinguishing the compensated from persistently poor readers that might account for their different outcomes.: MethodsUsing functional magnetic resonance imaging, we studied three groups of young adults, ages 18.5–22.5 years, as they read pseudowords and real words: 1) persistently poor readers (PPR; n = 24); 2) accuracy improved (compensated) readers (AIR; n = 19); and 3) nonimpaired readers (NI, n = 27).: ResultsCompensated readers, who are accurate but not fluent, demonstrate a relative underactivation in posterior neural systems for reading located in left parietotemporal and occipitotemporal regions. Persistently poor readers, who are both not fluent and less accurate, activate posterior reading systems but engage them differently from nonimpaired readers, appearing to rely more on memory-based rather than analytic word identification strategies.: ConclusionsThese findings of divergent neural outcomes as young adults are both new and unexpected and suggest a neural basis for reading outcomes of compensation and persistence in adults with childhood dyslexia. [Copyright &y& Elsevier]

Background: Converging evidence indicates a functional disruption in the neural systems for reading in adults with dyslexia. We examined brain activation patterns in dyslexic and nonimpaired children during pseudoword and real-word reading tasks that required phonologic analysis (i.e., tapped the problems experienced by dyslexic children in sounding out words).Methods: We used functional magnetic resonance imaging (fMRI) to study 144 right-handed children, 70 dyslexic readers, and 74 nonimpaired readers as they read pseudowords and real words.Results: Children with dyslexia demonstrated a disruption in neural systems for reading involving posterior brain regions, including parietotemporal sites and sites in the occipitotemporal area. Reading skill was positively correlated with the magnitude of activation in the left occipitotemporal region. Activation in the left and right inferior frontal gyri was greater in older compared with younger dyslexic children.Conclusions: These findings provide neurobiological evidence of an underlying disruption in the neural systems for reading in children with dyslexia and indicate that it is evident at a young age. The locus of the disruption places childhood dyslexia within the same neurobiological framework as dyslexia, and acquired alexia, occurring in adults. [ABSTRACT FROM AUTHOR]

Compares the behavioral qualities between gifted and learning disabled children. Demonstration of lower levels of behavioral problems in low gifted children; Difficulty of parenting in highly gifted children; Importance of increased activity associated with exploration and experimentation for intellectual growth in gifted children.

ABSTRACT. Objective. The outcome in adolescence of children diagnosed as dyslexic during the early years of school was examined in children prospectively identified in childhood and continuously followed to young adulthood. This sample offers a unique opportunity to investigate a prospectively identified sample of adolescents for whom there is no question of the childhood diagnosis and in whom highly analytic measures of reading and language can be administered in adolescence. Design. Children were recruited from the Connecticut Longitudinal Study, a cohort of 445 children representative of those children entering public kindergarten in Connecticut in 1983. Two groups were selected when the children were in grade 9: children who met criteria for persistent reading disability in grades 2 through 6 (persistently poor readers [PPR]; n = 21) and a comparison group of nondisabled children, subdivided into average readers (n = 35) and superior readers (n = 39). In grade 9, each child received a comprehensive assessment of academic, language, and other cognitive skills. Results. Measures of phonological awareness (but not orthographic awareness) were most significant in differentiating the 3 reading groups, with smaller contributions from measures of word finding and digit-span. Academic measures that best separated good from poor readers were decoding and spelling, whereas measures of math and reading comprehension did not. Measures of phonological awareness, followed next by teacher rating of academic skills were the best predictors of decoding, reading rate, and reading accuracy. In contrast, the best predictor of reading comprehension was word finding, with digit span and socioeconomic status also contributing significantly. Using a growth curve model (quadratic model of growth to a plateau) all 3 groups demonstrated similar patterns of growth over time, with the superior group outperforming the average group, and the average group outperforming the PPR group. Ther... [ABSTRACT FROM AUTHOR]

Presents a study to investigate the effects of estrogen on brain activation patterns in post-menopausal women as they performed verbal and nonverbal working memory tasks. Design; Setting; Patients; Intervention; Main outcome measures; Results; Conclusions.

Highlights a study which identified the subtypes of reading disabilities in several children. Details on the children's cognitive and language functions; In-depth look at a cluster analysis; Methodology used to conduct the study; Results of the study.

Presents a study which was conducted to investigate the location and extent of the functional disruption in neural systems which causes dyslexia. Methodologyy used to conduct the study; Results of the study.

Abstract. The Yale Children's Inventory rating scales for completion by parents were developed to improve the ability of clinicians and researchers to evaluate the school-related problems of children. The inventory consists of 11 narrow-band and two broad-band scales, the Behavioral and the Cognitive. The concurrent and predictive validity of the Yale Children's Inventory scales are reported in a school-based sample of 103 boys. External criterion variables were obtained from parents, teachers, and standardized tests administered to the children. We found that the Attention scale overlaps both broad-band domains, indicating the importance and the intrinsic relationship of attention to both behavioral and cognitive functions, which supports the Diagnostic and Statistical Manual of Mental Disorders, ed 3 nosology for disorders of attention and activity regulation. It also increases the number of children whose assessment may be enhanced by the availability of systematic parent report forms. Pediatrics 1988;81:562-571; attention deficit disorder, behavior, school-related problems, learning disability. [ABSTRACT FROM AUTHOR]

Abstract. In this study we analyzed some of the cognitive components that may constitute attention deficit disorder. It consisted of a double-blind, drug-placebo study of 12 children being treated with three doses of methylphenidate and placebo. Results of an attentional test battery, teacher and parent ratings, and blood levels of methylphenidate are reported. In general, performance was best with 0.6 mg/kg of methylphenidate (the highest dose tested) and worst with placebo. It is argued that no single test provides a complete assessment of attentional deficits and that methylphenidate can improve performance by affecting the allocation of cognitive resources to a task. [ABSTRACT FROM AUTHOR]

Abstract. Despite the frequent use of methylphenidate (MPH) in school-aged children with disorders of attention, impulsivity, and activity regulation (attention deficit disorder, ADD), little is known of its clinical pharmacology. The pharmacokinetics of MPH as well as its effects on growth hormone and prolactin were examined after oral administration in 14 boys with ADD ranging in age from 7 to 12 years (mean 10.4 years). Peak concentrations determined in these acute studies were compared with concentrations obtained two hours after MPH administration in another group of children with ADD who were receiving MPH chronically. After a lag phase of approximately 1/2 to 1 hour, MPH reached a peak plasma concentration at 2.5 +/- 0.65 hours after 0.34 mg/kg and 1.9 +/- 0.82 hours after 0.65 mg/kg (mean +/- SD). Terminal half-lives were 2.53 +/- 0.59 and 2.61 +/- 0.29 hours after administration of 0.34 and 0.65 mg/kg, respectively. Observed maximal concentrations ranged from 11.2 +/- 2.7 ng/ml after administration of 0.34, and 20.2 +/- 9.1 ng/ml after administration of 0.65 mg/kg. The mean area under the curve after administration of 0.65 mg/kg was approximately double that calculated at 0.34 mg/kg. Plasma growth hormone increased significantly from an initial (pre-MPH) mean concentration of 4.4 to peak at two hours at 10.5 ng/ml. Prolactin concentration declined significantly from a pre-MPH level of 9.5 to a nadir at 1 1/2 hours of 3.80 ng/ml, supporting the notion that MPH is acting via central dopaminergic mechanisms. MPH concentratious in children receiving doses of 0.34 mg/kg chronically averaged 8.00 +/- 0.91 at two hours, after medication, approximating the mean concentration at the same time observed in the acute study. The concentration of MPH in single "spot" samples obtained at two to three hours after administration of medication were significantly correlated with the percentage of improvement in the abbreviated Conners rating scale, indicating a rela... [ABSTRACT FROM AUTHOR]

Abstract. Two pre-school-aged patients with a history of prenatal exposure to ethanol had abnormal head size and developmental delay. Both children were strikingly similar in physical appearance, behavior, and cognitive dysfunction. Facial features were typical of fetal alcohol syndrome. Head circumference >97th percentile without hydrocephalus and no evidence of prenatal or postnatal growth failure were unusual for ethanol teratogenicity. Each child had a similar pattern of verbal and behavioral dysfunctions characterized by (1) marked hypervigilence, (2) distractability, and (3) cognitive confusion manifested as anxiety and behavioral disorganization. It is suggested that a history of prenatal exposure to ethanol associated with (1) large head circumference, (2) facial features of fetal alcohol syndrome, and (3) early developmental delay, particularly in language acquisition, and impaired modulation of attention and arousal may represent a possible new effect of alcohol teratogenicity. Pediatrics 68:850-855, 1981; fetal alcohol syndrome, fetal alcohol effects, teratogenicity, language dysfunction, developmental delay. [ABSTRACT FROM AUTHOR]

Focuses on a study which examined the prevalence of reading disability in boys and girls. Clinical characteristics of subjects; Criterion measures used; Characteristics of reading disability in the subjects.

Studies the validity of distinguishing children with reading disabilities according to discrepancy and low-achievement definitions. Failure of the results to support the validity of discrepancy versus low achievement definitions; Differences between those with impaired reading who met discrepancy definitions and those with low reading achievement definitions.

Comments on the argument made by Strauss in the January 2002 issue of this journal, which is thought to be against the scientific method and against accountability in education. Criticism by Strauss of the National Institute of Child Health and Human Development (NICHD) research for insisting that treatment efficacy for reading instruction be based on experimental studies; Approach to helping children who have difficulty reading.

Provides evidence for a sex difference in the functional organization of the brain for language and indicates that these variations exist at the level of phonological processing. Use of echo-planar functional magnetic resonance imaging to study subjects; Brain lateralization during phonological tasks.

Discusses some of the pitfalls in clinical research in attention deficit disorder (ADD) in children. Issue posed by the definition of the disorder; Diagnostic criteria of ADD; Assessment of pharmacotherapy for the disorder; Failure to consider other management procedures for ADD.

Editorial. Comments on the suitability of estrogen as a treatment for Alzheimer's disease (AD) in postmenopausal women. Effects of estrogen treatment on the reproductive, cardiovascular, skeletal, and neuronal systems; Whether estrogen administered in the early stages of postmenopausal period can prevent or delay the onset of AD; Why laboratory experimentation does not always translate to clinical application.

Comments on an article on medication overuse in the treatment of attention deficit hyperactivity disorder, previously published in the October 21, 1988, issue of the 'Journal of the American Medical Association.' Review of relevant literature; Fraud in research on the treatment of the disorder.

We examine the dilemmas faced by a medical student with dyslexia who wonders whether he should "out" himself to faculty to receive the accommodations entitled by federal law. We first discuss scientific evidence on dyslexia's prevalence, unexpected nature, and neurobiology. We then examine the experiences of medical students who have revealed their dyslexia to illustrate the point that, far too often, attending physicians who know little about dyslexia can misperceive the motives or behavior of students with dyslexia. Because ignorance and misperception of dyslexia can result in bias against students with dyslexia, we strongly recommend a mandatory course for faculty that provides a basic scientific and clinical overview of dyslexia to facilitate greater understanding of dyslexia and support for students with dyslexia. [ABSTRACT FROM AUTHOR]

A response by Sally Shaywitz to a letter to the editor about her article "Dyslexia," in the January 29, 1998 issue is presented.

Presents a review of advances in medical knowledge and the implication for treating patients with a possible reading or learning disability, developmental dyslexia. Epidemiology of dyslexia; Neurobiologic influences; Cognitive influences; Implications of the phonologic model of dyslexia; Approach to the diagnostic evaluation; Evaluation of school-age children; Special considerations in younger and older age groups; Diagnosis; Management.

Presents a response by Salley E. Shaywitz, Jack M. Fletcher and Michael D. Escobar to a letter to the editor about their article 'Prevalence of Reading Disability in Boys and Girls: Results of the Connecticut Longitudinal Study,' in the 1990 issue of the 'Journal of the American Medical Association.'

Examines distinctions and interrelationships between attention deficit disorder (ADD), learning disability and oppositional/conduct disorder in children. Referral patterns of children with learning and behavioral disorders; Relationship between referral source and diagnosis of ADD; Diagnosis of ADD according to diagnostic method; Composition of referral cohort according to method of diagnosis.

Introduces papers about aspects of attention deficit disorder (ADD). Definition and dimensions of ADD; Distinctions and interrelationships within subtypes of ADD and between ADD and learning disability; Neural mechanisms influencing ADD; Practical details of therapies for ADD; Learning difficulties and academic achievement deficiencies of children with ADD.

Abstract: We studied error-related negativity (ERN) and error positivity (Pe) during a discrimination task in 319 unmedicated children divided into subtypes of ADHD (Not-ADHD/inattentive/combined), learning disorder (Not-LD/reading/math/reading+math), and oppositional defiant disorder. Response-locked ERPs contained a frontocentral ERN and posterior Pe. Error-related negativity and positivity exhibited larger amplitude and later latency than corresponding waves for correct responses matched on reaction time. ADHD did not affect performance on the task. The ADHD/combined sample exceeded controls in ERN amplitude, perhaps reflecting patients’ adaptive monitoring efforts. Compared with controls, subjects with reading disorder and reading+math disorder performed worse on the task and had marginally more negative correct-related negativities. In contrast, Pe/Pc was smaller in children with reading+math disorder than among subjects with reading disorder and Not-LD participants; this nonspecific finding is not attributable to error processing. The results reflect anomalies in error processing in these disorders but further research is needed to address inconsistencies in the literature. [Copyright &y& Elsevier]

Converging evidence from a number of lines of investigation indicates that dyslexia represents a disorder within the language system and more specifically within a particular subcomponent of that system, phonological processing. Recent advances in imaging technology, particularly the development of functional magnetic resonance imaging (fMRI), provide evidence of a neurobiological signature for dyslexia, specifically a disruption of 2 left hemisphere posterior brain systems, 1 parietal-temporal, the other occipital-temporal, with compensatory engagement of anterior systems around the inferior frontal gyrus and a posterior (right occipital-temporal) system. Furthermore, good evidence indicates a computational role for the left occipital-temporal system: the development of fluent (automatic) reading. In addition, fMRI studies of young adults with reading difficulties followed prospectively and longitudinally from age 5 through their mid 20s suggests that there may be 2 types of reading difficulties, 1 primarily reflecting a genetic basis, the other, and far more common, reflecting environmental influences. The brain systems for reading are malleable and their disruption in children with dyslexia may be remediated by provision of an evidence-based, effective reading intervention. These studies offer the promise for more precise identification and effective management of dyslexia in children, adolescents, and adults. [ABSTRACT FROM AUTHOR]

The authors report findings on reading and IQ from a contemporary study of 145 individually tested incarcerated men and women in two maximum-security prisons in Louisiana. To their knowledge this study is the first to use the definition of dyslexia from the First Step Act (FSA) and the first to incorporate an IQ measure to differentiate those with dyslexia from individuals with cognitive impairment. The authors' findings indicate that almost half (47%) of the participants are classified as having dyslexia, 36% proficient, and 17% cognitive impairment. Both dyslexic prisoners and nondyslexic prisoners reported academic and behavioral problems in school that led to decreased years in school and decreased high school graduation rates, with 87% reporting dropping out of school with many inmates dropping out in middle school (mean age of completion of 9.6 years of school), 97% reporting having been in special education or received accommodations, and 59% having failed to receive a high school diploma or equivalency. The authors note that although the FSA calls for the Bureau of Prisons to screen prisoners for dyslexia using a screener that is evidencebased, with proven psychometrics for validity, efficiency and low cost, as well as readily available, a screener is not a diagnostic instrument and we discuss the next steps after inmates are screened as being dyslexic. [ABSTRACT FROM AUTHOR]

: BackgroundWe investigated the impact of stimulus probability and sequence on performance and event-related potentials of 310 children classified into 12 combinations of attention-deficit/hyperactivity disorder (Not–attention-deficit/hyperactivity disorder, Inattentive and Combined subtypes) with presence/absence of reading disorder and math disorder.: MethodsSubjects pressed buttons to displays of the letters O and X, which were presented with probabilities of either .17/.83 or .50/.50. Greater response selection was required in the .17/.83 condition.: ResultsStimulus probability had comparable effects on all diagnostic groups. The extent of mismatch between a stimulus and preceding events elicited less systematic increases in errors, P3b latency, and P3b amplitude among both attention-deficit/hyperactivity disorder subtypes than controls. Mismatch with preceding trials more greatly reduced math disorder and reading disorder + math disorder children’s speed in the Rare task and accuracy in both conditions. Math disorder and reading disorder + math disorder subjects also registered less the effects of alternations of the infrequent O on N2 amplitude and on P3b latency.: ConclusionsMath disorder and reading disorder + math disorder youngsters’ lower sensitivity to sequence irregularity in their event-related potentials along with greater disruption of performance suggest working memory deficits that adversely affected response selection. Comorbidity of attention-deficit/hyperactivity disorder and reading disorder did not affect the results. [ABSTRACT FROM AUTHOR]

Identifying change at the individual level is an important goal for researchers, educators, and clinicians. We present a set of statistical procedures for identifying individuals who depart from a normative change. Using Latent Change Scores models (LCS), we illustrate how the Individual Likelihood computed from a statistical model for change (lL) and from an alternative unrestricted model (ILsat) can be used to identify atypical trajectories in situations with several measurement occasions. Using LCS and linear regression, we also show how the observed and latent change residuals can be used to identify atypical individual change between 2 measurement occasions. We apply these methods to a measure of general verbal ability (from WISC-R), from a large sample of individuals assessed every 2 years from Grade I to 9. We demonstrate the efficiency of these techniques, illustrate their use to identify individual change in longitudinal data, and discuss potential applications in developmental research. [ABSTRACT FROM AUTHOR]

Background Functional connectivity analyses of functional magnetic resonance imaging data are a powerful tool for characterizing brain networks and how they are disrupted in neural disorders. However, many such analyses examine only one or a small number of a priori seed regions. Studies that consider the whole brain frequently rely on anatomic atlases to define network nodes, which might result in mixing distinct activation timecourses within a single node. Here, we improve upon previous methods by using a data-driven brain parcellation to compare connectivity profiles of dyslexic (DYS) versus nonimpaired (NI) readers in the first whole-brain functional connectivity analysis of dyslexia. Methods Whole-brain connectivity was assessed in children ( n = 75; 43 NI, 32 DYS) and adult ( n = 104; 64 NI, 40 DYS) readers. Results Compared to NI readers, DYS readers showed divergent connectivity within the visual pathway and between visual association areas and prefrontal attention areas; increased right-hemisphere connectivity; reduced connectivity in the visual word-form area (part of the left fusiform gyrus specialized for printed words); and persistent connectivity to anterior language regions around the inferior frontal gyrus. Conclusions Together, findings suggest that NI readers are better able to integrate visual information and modulate their attention to visual stimuli, allowing them to recognize words on the basis of their visual properties, whereas DYS readers recruit altered reading circuits and rely on laborious phonology-based "sounding out" strategies into adulthood. These results deepen our understanding of the neural basis of dyslexia and highlight the importance of synchrony between diverse brain regions for successful reading. [ABSTRACT FROM AUTHOR]

Developmental dyslexia is defined as an unexpected difficulty in reading in individuals who otherwise possess the intelligence and motivation considered necessary for fluent reading, and who also have had reasonable reading instruction. Identifying factors associated with normative and impaired reading development has implications for diagnosis, intervention, and prevention. We show that in typical readers, reading and IQ development are dynamically linked over time. Such mutual interrelationships are not perceptible in dyslexic readers, which suggests that reading and cognition develop more independently in these individuals. To our knowledge, these findings provide the first empirical demonstration of a coupling between cognition and reading in typical readers and a developmental uncoupling between cognition and reading in dyslexic readers. This uncoupling was the core concept of the initial description of dyslexia and remains the focus of the current definitional model of this learning disability. [ABSTRACT FROM PUBLISHER]

The authors applied linear dynamic models to longitudinal data to examine the dynamics of reading and cognition from 1st to 12th grade. They used longitudinal data (N = 445) from the Connecticut Longitudinal Study (S. E. Shaywitz, B. A. Shaywitz, J. M. Fletcher, & M. D. Escobar, 1990) to map the dynamic interrelations of various scales of the Wechsler Intelligence Scales for Children-Revised (i.e., Full, Performance, and Verbal) and specific markers of the Woodcock-Johnson Psycho-Educational Battery-Revised reading cluster (i.e., Letter-Word ID, Decoding, and Comprehension). The results of these analyses indicate that (a) there is a positive dynamic relation between reading and cognition across the selected age range; (b) this dynamic relation is symbiotic, with positive influences in both directions; (c) the influence from cognition to reading is stronger when considering the Wechsler Intelligence Scales for Children Performance-Revised Performance scale and weaker with the Verbal scale; (d) when examining the different Reading subtests, the influences from cognition are more apparent for Letter- Word ID and Comprehension and are less perceptible for Decoding; and (e) the dynamics of reading and cognition appear to be of stronger magnitude during 1st to 3rd grade, less strong during 4th to 8th grade, and weaker from 9th to 12th grade. [ABSTRACT FROM AUTHOR]

DYX2 on 6p22 is the most replicated reading disability (RD) locus. By saturating a previously identified peak of association with single nucleotide polymorphism markers, we identified a large polymorphic deletion that encodes tandem repeats of putative brain-related transcription factor binding sites in intron 2 of DCDC2. Alleles of this compound repeat are in significant disequilibrium with multiple reading traits. RT-PCR data show that DCDC2 localizes to the regions of the brain where fluent reading occurs, and RNA interference studies show that down-regulation alters neuronal migration. The statistical and functional studies are complementary and are consistent with the latest clinical imaging data for RD. Thus, we propose that DCDC2 is a candidate gene for RD. [ABSTRACT FROM AUTHOR]