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Developmental dyslexia (decoding-based reading disorder; RD) is a complex trait with multifactorial origins at the genetic, neural, and cognitive levels. There is evidence that low-level sensory-processing deficits precede and underlie phonological problems, which are one of the best-documented aspects of RD. RD is also associated with impairments in integrating visual symbols with their corresponding speech sounds. Although causal relationships between sensory processing, print–speech integration, and fluent reading, and their neural bases are debated, these processes all require precise timing mechanisms across distributed brain networks. Neural excitability and neural noise are fundamental to these timing mechanisms. Here, we propose that neural noise stemming from increased neural excitability in cortical networks implicated in reading is one key distal contributor to RD. [ABSTRACT FROM AUTHOR]

Speech signals contain information of both linguistic content and a talker's voice. Conventionally, linguistic and talker processing are thought to be mediated by distinct neural systems in the left and right hemispheres respectively, but there is growing evidence that linguistic and talker processing interact in many ways. Previous studies suggest that talker-related vocal tract changes are processed integrally with phonetic changes in the bilateral posterior superior temporal gyrus/superior temporal sulcus (STG/STS), because the vocal tract parameter influences the perception of phonetic information. It is yet unclear whether the bilateral STG is also activated by the integral processing of another parameter — pitch, which influences the perception of lexical tone information and is related to talker differences in tone languages. In this study, we conducted separate functional magnetic resonance imaging (fMRI) and event-related potential (ERP) experiments to examine the spatial and temporal loci of interactions of lexical tone and talker-related pitch processing in Cantonese. We found that the STG was activated bilaterally during the processing of talker changes when listeners attended to lexical tone changes in the stimuli and during the processing of lexical tone changes when listeners attended to talker changes, suggesting that lexical tone and talker processing are functionally integrated in the bilateral STG. It extends the previous study, providing evidence for a general neural mechanism of integral phonetic and talker processing in the bilateral STG. The ERP results show interactions of lexical tone and talker processing 500–800 ms after auditory word onset (a simultaneous posterior P3b and a frontal negativity). Moreover, there is some asymmetry in the interaction, such that unattended talker changes affect linguistic processing more than vice versa, which may be related to the ambiguity that talker changes cause in speech perception and/or attention bias to talker changes. Our findings have implications for understanding the neural encoding of linguistic and talker information. [ABSTRACT FROM AUTHOR]

Reading disability is a brain-based difficulty in acquiring fluent reading skills that affects significant numbers of children. Although neuroanatomical and neurofunctional networks involved in typical and atypical reading are increasingly well characterized, the underlying neurochemical bases of individual differences in reading development are virtually unknown. The current study is the first to examine neurochemistry in children during the critical period in which the neurocircuits that support skilled reading are still developing. In a longitudinal pediatric sample of emergent readers whose reading indicators range on a continuum from impaired to superior, we examined the relationship between individual differences in reading and reading-related skills and concentrations of neurometabolites measured using magnetic resonance spectroscopy. Both continuous and group analyses revealed that choline and glutamate concentrations were negatively correlated with reading and related linguistic measures in phonology and vocabulary (such that higher concentrations were associated with poorer performance). Correlations with behavioral scores obtained 24 months later reveal stability for the relationship between glutamate and reading performance. Implications for neurodevelopmental models of reading and reading disability are discussed, including possible links of choline and glutamate to white matter anomalies and hyperexcitability. These findings point to new directions for research on gene-brain-behavior pathways in human studies of reading disability. [ABSTRACT FROM AUTHOR]

Abstract: We employed brain–behavior analyses to explore the relationship between performance on tasks measuring phonological awareness, pseudoword decoding, and rapid auditory processing (all predictors of reading (dis)ability) and brain organization for print and speech in beginning readers. For print-related activation, we observed a shared set of skill-correlated regions, including left hemisphere temporoparietal and occipitotemporal sites, as well as inferior frontal, visual, visual attention, and subcortical components. For speech-related activation, shared variance among reading skill measures was most prominently correlated with activation in left hemisphere inferior frontal gyrus and precuneus. Implications for brain-based models of literacy acquisition are discussed. [Copyright &y& Elsevier]

Functional neuroimaging studies indicate that a primary marker of specific reading disability (RD) is reduced activation of left hemisphere (LH) posterior regions during performance of reading tasks. However, the severity of this disruption, and the extent to which these LH systems might be available for reading under any circumstances, is unclear at present. Experiment 1 examined the cortical effects of stimulus manipulations frequency, imageability, consistency) that have known facilitative effects on reading performance for both nonimpaired (NI) and RD readers. Experiment 2 examined stimulus repetition, another facilitative variable, in an additional sample of adolescent NI and RD readers. For NI readers, factors that made words easier to process were associated with relatively reduced activation. For RD readers, facilitative factors resulted in increased activation in these same reading-related sites, suggesting that the LH reading circuitry in adolescent RD is poorly trained but not wholly disrupted. [ABSTRACT FROM AUTHOR]

Background: Cannabis remains the most widely used illicit substance by adolescents and is typically consumed by this population in the context of ongoing tobacco use. Human studies have shown that both cannabis and tobacco exert effects on cognitive function; however, little is known about possible interacting effects of these drugs on brain function and cognition during adolescent development. Methods: Verbal learning and memory were assessed in 20 adolescent users of tobacco and cannabis and 25 adolescent tobacco users with minimal history of cannabis use. Functional magnetic resonance imaging was used to examine brain function and functional connectivity while a subset of these subjects performed a verbal working memory task. Results: Delayed recall of verbal stimuli deteriorated during nicotine withdrawal among cannabis users but not among comparison subjects. During high verbal working memory load, nicotine withdrawal selectively increased task-related activation of posterior cortical regions and was associated with disruption of frontoparietal connectivity in adolescent cannabis users relative to comparison subjects. Conclusions: These observations suggest that cannabis use during adolescent development may disrupt neurocircuitry supporting verbal memory formation and that deficits associated with disruption of these neurocircuits are unmasked during nicotine withdrawal. [Copyright &y& Elsevier]

Neuroimaging studies have suggested that across different written languages, skilled reading behavior is supported by similar, largely left hemisphere (LH), networks. In addition, recent studies of reading disability (RD) in monolingual readers, conducted in several languages, suggest a common neurobiological signature for this syndrome (disruption of LH posterior regions that support fluent reading). Thus, at the neurobiological level of analysis, reading and its disorders appear to be more similar than dissimilar across languages. In this article, we consider the neurobiology of reading development and RD in English language learners (ELL). There is some evidence suggesting that fluent bilingual readers tend to engage primarily overlapping circuits for both L1 and L2. There is, however, a paucity of neurobiological research on both reading development and RD in this population. Using the existing research on RD as a starting point, we consider in this article how developmental neuroimaging techniques might be applied to (1) help identify RD readers in the ELL populations, and (2) provide neurobiological outcome measures to help evaluate the efficacy of different approaches to the teaching of reading in English. [ABSTRACT FROM AUTHOR]

Cortical regions engaged by sentence processing were mapped using functional MRI. The influence of input modality (spoken word vs. print input) and parsing difficulty (sentences containing subject-relative vs. object-relative clauses) was assessed. Auditory presentation was associated with pronounced activity at primary auditory cortex and across the superior temporal gyrus bilaterally. Printed sentences by contrast evoked major activity at several posterior sites in the left hemisphere, including the angular gyrus, supramarginal gyrus, and the fusiform gyrus in the occipitotemporal region. In addition, modality-independent regions were isolated, with greatest overlap seen in the inferior frontal gyrus (IFG). With respect to sentence complexity, object-relative sentences evoked heightened responses in comparison to subject-relative sentences at several left hemisphere sites, including IFG, the middle/superior temporal gyrus, and the angular gyrus. These sites showing modulation of activity as a function of sentence type, independent of input mode, arguably form the core of a cortical system essential to sentence parsing. [Copyright &y& Elsevier]

Converging evidence from a number of neuroimaging studies, including our own, suggest that fluent word identification in reading is related to the functional integrity of two left hemisphere posterior systems: a temporo-parietal system and a ventral occipito-temporal system. These posterior systems are functionally disrupted in developmental dyslexia. Reading disabled, relative to nonimpaired, readers demonstrate heightened reliance on both inferior frontal and right hemisphere posterior regions, presumably in compensation for the LH posterior difficulties. We propose a neurobiological account suggesting that for normally developing readers the temporo-parietal system predominates at first, and is associated with aspects of processing critical in learning to integrate orthography with phonological and lexical-semantic features of printed words. The occipito-temporal system, by contrast, constitutes a fast, late-developing, word-identification system that underlies fluent word recognition in skilled readers. [ABSTRACT FROM AUTHOR]

Converging evidence from a number of neuroimaging studies, including our own, suggest that fluent word identification in reading is related to the functional integrity of two consolidated left hemisphere (LH) posterior systems: a dorsal (temporo-parietal) circuit and a ventral (occipito-temporal) circuit. This posterior system is functionally disrupted in developmental dyslexia. Reading disabled readers, relative to nonimpaired readers, demonstrate heightened reliance on both inferior frontal and right hemisphere posterior regions, presumably in compensation for the LH posterior difficulties. We propose a neurobiological account suggesting that for normally developing readers the dorsal circuit predominates at first, and is associated with analytic processing necessary for learning to integrate orthographic features with phonological and lexical-semantic features of printed words. The ventral circuit constitutes a fast, late-developing, word identification system which underlies fluent word recognition in skilled readers. MRDD Research Reviews 6:207–213, 2000. © 2000 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Examines functional connectivity between angular gyrus, and the occipital and temporal lobe sites. Evidence of dysfunction at posterior brain regions in individuals with developmental dyslexia; Compensatory role of the right hemisphere posterior regions; Confinement of neurobiological anomalies in development dyslexia at the phonological processing domain.

Provides experimental evidence for the psychological reality of the concept of neighborhood activation and tests the claim that letter positions yielding neighbors require greater processing than positions not yielding neighbors. Visual work recognition; Search models and activation models of word recognition.

Proposes a model of word recognition which assumes that when a word is encountered, the first available orthographic code activates all lexical entries that are positionally consistent with that information. Role of component information in word processing; Component information and cohort models of speech perception; Role of attention.

Determines the existence of flexible coding in visual word recognition. Differential dependence on phonological versus orthographic information; Presence or absence of pseudohomophones in the nonword context of a lexical decision task; Use of a double lexical decision paradigm.

Educational neuroscience approaches have helped to elucidate the brain basis of Reading Disability (RD) and of reading intervention response; however, there is often limited translation of this knowledge to the broader scientific and educational communities. Moreover, this work is traditionally lab‐based, and thus the underlying theories and research questions are siloed from classroom practices. With growing awareness of the neurobiological origins of RD and increasing popularity of putative 'brain‐based' approaches in clinics and classrooms, it is imperative that we create more direct and bidirectional communication between scientists and practitioners. Such direct collaborations can help dispel neuromyths, and lead to increased understanding of the promises and pitfalls of neuroscience approaches. Moreover, direct partnerships between researchers and practitioners can lead to greater ecological validity in study designs to improve upon the translational potential of findings. To this end, we have forged collaborative partnerships, and built cognitive neuroscience laboratories within independent reading disabilities schools. This approach affords frequent and ecologically valid neurobiological assessment as children's reading improves in response to intervention. It also permits the creation of dynamic models of leading and lagging relationships of students' learning, and identification of individual‐level predictors of intervention response. The partnerships also provide in‐depth knowledge of student characteristics and classroom practices, which, when combined with the data we acquire, may facilitate optimisation of instructional approaches. In this commentary, we discuss the creation of our partnerships, the scientific problem we are addressing (variable response to reading intervention), and the epistemological significance of researcher–practitioner bi‐directional learning. [ABSTRACT FROM AUTHOR]

There is now considerable evidence regarding the types of interventions that are effective at remediating reading disabilities on average. It is generally unclear, however, what predicts the magnitude of individual-level change following a given intervention. We examine new predictors of intervention gains that are theoretically grounded in computational models of reading and focus on individual differences in the functional organization of the reading system. Specifically, we estimate the extent to which children with reading disabilities (n = 118 3rd–4th graders) rely on two sources of information during an oral word reading task—print–speech correspondences and semantic imageability—before and after a phonologically-weighted intervention. We show that children who relied more on print–speech regularities and less on imageability preintervention had better intervention gains. In parallel, children who over the course of the intervention exhibited greater increases in their reliance on print–speech correspondences and greater decreases in their reliance on imageability, had better intervention outcomes. Importantly, these two factors were differentially related to specific reading task outcomes, with greater reliance on print–speech correspondences associated with pseudoword naming, while (lesser) reliance on imageability related to word reading and comprehension. We discuss the implications of these findings for theoretical models of reading acquisition and educational practice. Educational Impact and Implications Statement: Why do some children with reading disabilities show substantial gains when provided with an intervention program, whereas others show little to no improvement? Here we argue that such differences in improvement can be tied to the way in which different children read (reflecting the functional organization of their reading system). We measure how different children are impacted by two sources of information of words they read—print–speech correspondences (orthographic–phonological) and semantic imageability—before and after a phonologically-weighted intervention for children with reading disabilities. Results show that children who before the intervention relied more on orthographic–phonological knowledge, and less on semantic imageability, had greater reading skill gains over the intervention. Skill gains were also associated with changes children made in their use of these two sources of information over the intervention. These findings may help in detecting the children who may benefit more or less from a given intervention and advance us toward identifying an optimal intervention program for each individual based on the state of their reading system. [ABSTRACT FROM AUTHOR]

Rationale. 3,4-Methylenedioxymethamphetamine (MDMA or ecstasy) is a potent and selective serotonin neurotoxin whose use is growing among adolescents. Although cognitive deficits among adult MDMA users are well documented, little is known of the cognitive and brain functional sequelae of MDMA use during adolescence. Objective. We tested for evidence of cognitive deficits and changes in brain function in a pilot sample of adolescent MDMA users, who were compared with adolescent non-users of MDMA. Methods. Selective and divided attention and verbal working memory were examined in six adolescent MDMA users and six non-users of MDMA who were similar in age, gender, IQ, and other substance use. Brain function was assessed during performance of the working memory task using functional magnetic resonance imaging (fMRI). Results. MDMA users had significantly prolonged reaction times during tests of selective and divided attention, and failed to deactivate the left hippocampus normally during high verbal working memory load. Conclusions. MDMA use in adolescence may be associated with cognitive impairments and dysfunction of inhibitory circuits within the hippocampus. Further work is urgently needed to delineate the developmental impact and long-term functional and clinical significance of MDMA use during adolescence. [ABSTRACT FROM AUTHOR]

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]

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.

In this review, we focus on those studies using brain imaging modalities to examine children and adults with attention-deficit hyperactivity disorder (ADHD). The conceptualization of attention that frames our review stresses the adaptive function of attention systems in regulating and orchestrating operations of multiple processing systems to satisfy multiple and sometimes inconsistent goals, and to maintain behavioral coherence. More specifically, we postulate that attention should be conceptualized as consisting of multiple control systems, each of which is associated with a different repertoire of behaviors. A reasonable starting point is the posterior and anterior attentional systems proposed by Posner and associates. Recent functional brain imaging studies support such a notion, with perceptual selection involving the posterior system and executive function engaging distinct anterior frontal regions. To date, the morphometric studies as well as more recent functional imaging studies suggest that subjects with ADHD differ from controls primarily in more anterior brain regions as well as in anterior-striatal systems. Studies now in progress offer the promise of examining neural systems throughout the brain in individuals with ADHD, neural systems involving both anterior as well as posterior attentional systems. Although attention as a construct and ADHD as a disorder were historically described for the first time in the mid-to-late 19th century, it is now apparent that, despite the great progress within the last 4 decades, a full understanding of the neurobiology of ADHD must await the 21st century. MRDD Research Reviews 1999;5:185–190. © 1999 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Background: Spatial normalization plays an essential role in multi-subject MRI and functional MRI (fMRI) experiments by facilitating a common space in which group analyses are performed. Although many prominent adult templates are available, their use for pediatric data is problematic. Generalized templates for pediatric populations are limited or constructed using older methods that result in less ideal normalization. Objective: The Haskins pediatric templates and atlases aim to provide superior registration and more precise accuracy in labeling of anatomical and functional regions essential for all fMRI studies involving pediatric populations. Materials and methods: The Haskins pediatric templates and atlases were generated with nonlinear methods using structural MRI from 72 children (age range 7–14 years, median 10 years), allowing for a detailed template with corresponding parcellations of labeled atlas regions. The accuracy of these templates and atlases was assessed using multiple metrics of deformation distance and overlap. Results: When comparing the deformation distances from normalizing pediatric data between this template and both the adult templates and other pediatric templates, we found significantly less deformation distance for the Haskins pediatric template (P<0.0001). Further, the correct atlas classification was higher using the Haskins pediatric template in 74% of regions (P<0.0001). Conclusion: The Haskins pediatric template results in more accurate correspondence across subjects because of lower deformation distances. This correspondence also provides better accuracy in atlas locations to benefit structural and functional imaging analyses of pediatric populations. [ABSTRACT FROM AUTHOR]

This study utilized a neuroimaging task to assess working memory (WM) network recruitment during single word reading. Associations between WM and reading comprehension skills are well documented. Several converging models suggest WM may also contribute to foundational reading skills, but few studies have assessed this contribution directly. Two groups of children (77 developmental dyslexia (DD), 22 controls) completed a functional magnetic resonance imaging (fMRI) task to identify activation of a priori defined regions of the WM network. fMRI trials consisted of familiar word, pseudoword, and false font stimuli within a 1-back oddball task to assess how activation in the WM network differs in response to stimuli that can respectively be processed using word recognition, phonological decoding, or non-word strategies. Results showed children with DD recruited WM regions bilaterally in response to all stimulus types, whereas control children recruited left-lateralized WM regions during the pseudoword condition only. Group-level comparisons revealed activation differences in the defined WM network regions for false font and familiar word, but not pseudoword conditions. This effect was driven by increased activity in participants with DD in right hemisphere frontal, parietal, and motor regions despite poorer task performance. Findings suggest the WM network may contribute to inefficient decoding and word recognition strategies in children with DD. • Working memory contributes differently to early reading in children with dyslexia. • FMRI protocol localised working memory network during decoding and word recognition. • In strong readers, network activity increased during phonetic decoding trials only. • In poor readers, activity increased for all trial types despite lower task accuracy. • Working memory may act as compensatory system for early reading skills in dyslexia. [ABSTRACT FROM AUTHOR]

Despite reading being an essential and almost universal skill in the developed world, reading proficiency varies substantially from person to person. To study why, the fMRI field is beginning to turn from single-word or nonword reading tasks to naturalistic stimuli like connected text and listening to stories. To study reading development in children just beginning to read, listening to stories is an appropriate paradigm because speech perception and phonological processing are important for, and are predictors of, reading proficiency. Our study examined the relationship between behavioral reading-related skills and the neural response to listening to stories in the fMRI environment. Functional MRI were gathered in a 3T TIM-Trio scanner. During the fMRI scan, children aged approximately 7 years listened to professionally narrated common short stories and answered comprehension questions following the narration. Analyses of the data used inter-subject correlation (ISC), and representational similarity analysis (RSA). Our primary finding is that ISC reveals areas of increased synchrony in both high- and low-performing emergent readers previously implicated in reading ability/disability. Of particular interest are that several previously identified brain regions (medial temporal gyrus (MTG), inferior frontal gyrus (IFG), inferior temporal gyrus (ITG)) were found to "synchronize" across higher reading ability participants, while lower reading ability participants had idiosyncratic activation patterns in these regions. Additionally, two regions (superior frontal gyrus (SFG) and another portion of ITG) were recruited by all participants, but their specific timecourse of activation depended on reading performance. These analyses support the idea that different brain regions involved in reading follow different developmental trajectories that correlate with reading proficiency on a spectrum rather than the usual dichotomy of poor readers versus strong readers. [ABSTRACT FROM AUTHOR]

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.

Understanding how pre‐literate children's language abilities and neural function relate to future reading ability is important for identifying children who may be at‐risk for reading problems. Pre‐literate children are already proficient users of spoken language and their developing brain networks for language become highly overlapping with brain networks that emerge during literacy acquisition. In the present longitudinal study, we examined language abilities, and neural activation and connectivity within the language network in pre‐literate children (mean age = 4.2 years). We tested how language abilities, brain activation, and connectivity predict children's reading abilities 1 year later (mean age = 5.2 years). At Time 1, children (n = 37) participated in a functional near infrared spectroscopy (fNIRS) experiment of speech processing (listening to words and pseudowords) and completed a standardized battery of language and cognitive assessments. At Time 2, children (n = 28) completed standardized reading assessments. Using psychophysiological interaction (PPI) analyses, we observed significant connectivity between the left IFG and right STG in pre‐literate children, which was modulated by task (i.e., listening to words). Neural activation in left IFG and STG and increased task‐modulated connectivity between the left IFG and right STG was predictive of multiple reading outcomes. Increased connectivity was associated later with increased reading ability. [ABSTRACT FROM AUTHOR]

Word learning is critical for the development of reading and language comprehension skills. Although previous studies have indicated that word learning is compromised in children with reading disability (RD) or developmental language disorder (DLD), it is less clear how word learning difficulties manifest in children with comorbid RD and DLD. Furthermore, it is unclear whether word learning deficits in RD or DLD include difficulties with offline consolidation of newly learned words. In the current study, we employed an artificial lexicon learning paradigm with an overnight design to investigate how typically developing (TD) children (N = 25), children with only RD (N = 93), and children with both RD and DLD (N = 34) learned and remembered a set of phonologically similar pseudowords. Results showed that compared to TD children, children with RD exhibited: (i) slower growth in discrimination accuracy for cohort item pairs sharing an onset (e.g. pibu‐pibo), but not for rhyming item pairs (e.g. pibu‐dibu); and (ii) lower discrimination accuracy for both cohort and rhyme item pairs on Day 2, even when accounting for differences in Day 1 learning. Moreover, children with comorbid RD and DLD showed learning and retention deficits that extended to unrelated item pairs that were phonologically dissimilar (e.g. pibu‐tupa), suggestive of broader impairments compared to children with only RD. These findings provide insights into the specific learning deficits underlying RD and DLD and motivate future research concerning how children use phonological similarity to guide the organization of new word knowledge. [ABSTRACT FROM AUTHOR]

In a quasiregular orthography like English, children inevitably encounter irregular words during reading. Previous research suggests successful reading of an irregular word depends at least partially on a child's ability to address the mismatch between decoded form and stored word pronunciation, referred to as a child's set for variability, and the word's relative transparency, measured here using a spelling to pronunciation transparency rating. Item-level analyses were used to explore the relationship between general child performance on the set for variability mispronunciation task, word specific set for variability (predicting reading of that word), spelling to pronunciation transparency rating, and irregular word reading. Significant predictors included general word reading, general set for variability performance, and item-specific set for variability performance; word frequency and spelling to pronunciation transparency rating; and an interaction between word reading and the transparency rating. Results underscore the importance of considering both general and item-specific factors affecting irregular word reading. [ABSTRACT FROM AUTHOR]

Objective: Decreased activation to print in the left ventral, dorsal, and anterior pathways has been implicated in readers with dyslexia (DRs) but also is characteristic for typical beginning readers. Because most studies have compared DRs with their age-matched peers, the observed results could represent a dyslexia phenotype or a developmental delay. This study aimed to disentangle reading and dyslexia effects using 2 control groups matched for age and skill and a longitudinal design.Method: Brain response for print was compared in DRs and typical readers (TRs) who, at the beginning of schooling (time point 1 [TP]; 6-7 years old), read on average 3 words per minute, as did DRs at TP1, but improved their reading to an average level, and advanced readers (ARs) who at TP1 read as well as DRs 2 years later (TP3; 8-9 years old). The TR and DR groups were tracked longitudinally to observe neurodevelopmental changes.Results: At TP1, DRs did not differ from TRs. Over time, only TRs developed a neural circuit for reading in the left inferior frontal and fusiform gyri. At TP3, DRs exhibited hypo-activation in these areas compared with age-matched (TRs at TP3) and reading-matched (ARs at TP1) controls. At TP3, TRs showed hypo-activation in the left frontal and bilateral ventral occipital regions compared with ARs, but these effects were nonoverlapping with DR hypo-activations and are partly explained by IQ.Conclusion: Decreased activation of the left fusiform and inferior frontal gyri to print in DRs results from an atypical developmental trajectory of reading and cannot be explained solely by lower reading skills. [ABSTRACT FROM AUTHOR]

• 75 adolescents read and heard time-locked narratives during an fMRI scan. • Inter-subject correlation (ISC) was used to analyze reading ability's impact. • ISC was more sensitive to individual differences in reading ability than GLMs. • Reading ability affects brain activity in more regions than previously thought. • Worse readers had more idiosyncratic responses than better readers across the brain. Recent work using fMRI inter-subject correlation analysis has provided new information about the brain's response to video and audio narratives, particularly in frontal regions not typically activated by single words. This approach is very well suited to the study of reading, where narrative is central to natural experience. But since past reading paradigms have primarily presented single words or phrases, the influence of narrative on semantic processing in the brain – and how that influence might change with reading ability – remains largely unexplored. In this study, we presented coherent stories to adolescents and young adults with a wide range of reading abilities. The stories were presented in alternating visual and auditory blocks. We used a dimensional inter-subject correlation analysis to identify regions in which better and worse readers had varying levels of consistency with other readers. This analysis identified a widespread set of brain regions in which activity timecourses were more similar among better readers than among worse readers. These differences were not detected with standard block activation analyses. Worse readers had higher correlation with better readers than with other worse readers, suggesting that the worse readers had "idiosyncratic" responses rather than using a single compensatory mechanism. Close inspection confirmed that these differences were not explained by differences in IQ or motion. These results suggest an expansion of the current view of where and how reading ability is reflected in the brain, and in doing so, they establish inter-subject correlation as a sensitive tool for future studies of reading disorders. [ABSTRACT FROM AUTHOR]

• Individuals with lower phonological skills show higher subphonemic sensitivity. • Higher subphonemic sensitivity indicates finer-grained phonological representations. • Overspecified phonological representations may indicate reading difficulties. Many studies have established a link between phonological abilities (indexed by phonological awareness and phonological memory tasks) and typical and atypical reading development. Individuals who perform poorly on phonological assessments have been mostly assumed to have underspecified (or "fuzzy") phonological representations, with typical phonemic categories, but with greater category overlap due to imprecise encoding. An alternative posits that poor readers have overspecified phonological representations, with speech sounds perceived allophonically (phonetically distinct variants of a single phonemic category). On both accounts, mismatch between phonological categories and orthography leads to reading difficulty. Here, we consider the implications of these accounts for online speech processing. We used eye tracking and an individual differences approach to assess sensitivity to subphonemic detail in a community sample of young adults with a wide range of reading-related skills. Subphonemic sensitivity inversely correlated with meta-phonological task performance, consistent with overspecification. [ABSTRACT FROM AUTHOR]

Epidemiological population studies highlight the presence of substantial individual variability in reading skill, with approximately 5–10% of individuals characterized as having specific reading disability (SRD). Despite reported substantial heritability, typical for a complex trait, the specifics of the connections between reading and the genome are not understood. Recently, the SETBP1 gene has been implicated in several complex neurodevelopmental syndromes and disorders that impact language. Here, we examined the relationship between common polymorphisms in this gene, reading, and reading associated behaviors using data from an ongoing project on the genetic basis of SRD (n = 135). In addition, an exploratory analysis was conducted to examine the relationship between SETBP1 and brain activation using functional magnetic resonance imaging (fMRI; n = 73). Gene-based analyses revealed a significant association between SETBP1 and phonological working memory, with rs7230525 as the strongest associated single nucleotide polymorphism (SNP). fMRI analysis revealed that the rs7230525-T allele is associated with functional neural activation during reading and listening to words and pseudowords in the right inferior parietal lobule (IPL). These findings suggest that common genetic variation within SETBP1 is associated with reading behavior and reading-related brain activation patterns in the general population. • rs7230525-T allele is associated with lower scores on phonological working memory. • rs7230525-T allele is associated with functional neural activation in the right IPL. • Common SETBP1 variants affect multiple components of reading. [ABSTRACT FROM AUTHOR]

Abstract Recent evidence has shown that convergence of print and speech processing across a network of primarily left-hemisphere regions of the brain is a predictor of future reading skills in children, and a marker of fluent reading ability in adults. The present study extends these findings into the domain of second-language (L2) literacy, through brain imaging data of English and Hebrew L2 learners. Participants received an fMRI brain scan, while performing a semantic judgement task on spoken and written words and pseudowords in both their L1 and L2, alongside a battery of L1 and L2 behavioural measures. Imaging results show, overall, a similar network of activation for reading across the two languages, alongside significant convergence of print and speech processing across a network of left-hemisphere regions in both L1 and L2 and in both cohorts. Importantly, convergence is greater for L1 in occipito-temporal regions tied to automatic skilled reading processes including the visual word-form area, but greater for L2 in frontal regions of the reading network, tied to more effortful, active processing. The main groupwise brain effects tell a similar story, with greater L2 than L1 activation across frontal, temporal and parietal regions, but greater L1 than L2 activation in parieto-occipital regions tied to automatic mapping processes in skilled reading. These results provide evidence for the shifting of the reading networks towards more automatic processing as reading proficiency rises and the mappings and statistics of the new orthography are learned and incorporated into the reading system. Highlights • Extent of convergence of print and speech processing in L1 and L2 was examined. • Greater L1 convergence in posterior ROIs was associated with skilled automatic reading. • Greater L2 convergence in frontal ROIs was associated with active effortful reading. • Evidence of proficiency-related shift to automaticity in reading networks. [ABSTRACT FROM AUTHOR]

As children learn to read, they become sensitive to context-dependent vowel pronunciations in words, considered a form of statistical learning. The work of Treiman and colleagues demonstrated that readers' vowel pronunciations depend on the consonantal context in which the vowel occurs and reading experience. Using explanatory item-response models we examined child- and nonword-factors associated with children's assignment of more versus less frequent grapheme-phoneme correspondences (GPC) to vowel pronunciations as a function of rime coda in monosyllabic nonwords. Students (N = 96) in grades 2-5 read nonwords in which more versus less frequent vowel GPCs were wholly supported or partially favored by the rime unit. Use of less frequent vowel GPCs was predicted by set for variability, word reading, and rime support for the context-dependent vowel pronunciation. We interpret the results within a developmental word reading model in which initially incomplete and oversimplified GPC representations become more context dependent with reading experience. [ABSTRACT FROM AUTHOR]

To investigate the neural basis of a common statistical learning mechanism involved in motor sequence learning and decoding, we recorded brain activation from participants during a serial reaction time (SRT) task and a word reading task using functional magnetic resonance imaging. In the SRT task, a manual response was made depending on the location of a visual cue, and the order of the locations was either fixed or random. In the word reading task, visual words were passively presented. In the inferior frontal gyrus pars triangularis (IFGpTr) and the insula, differences in activation between the ordered and random condition in the SRT task and activation to printed words in the word reading task were correlated with the participants' decoding ability. We speculate that extraction of statistically predictable patterns in the IFGpTr and insula contributes to both motor sequence learning and orthographic learning, and therefore predicts individual differences in decoding skill. [ABSTRACT FROM AUTHOR]

The article focuses on the neurobiology of dyslexia. Topics include neuroscience confirms the importance of systematic phonics instruction, neuroimaging has led to new ideas about how dyslexia might be treated and specific brain regions and pathways are involved in reading, and educational neuroscience remains in early stages, but the immediate relevance for the classroom is emerging.

Studies of the role of phonological representations in learning to read have almost exclusively focused on speech perception. In the current study, we examined links between sensorimotor control of speech, reading, and reading-related abilities. We studied two languages, English and Dutch, which vary in the regularity of their spelling-to-sound mappings. There were 236 American and Dutch children, 4 to 8 years old, who performed an altered auditory feedback task in which the first formant of the /ɛ/ vowel was altered. A stronger response to altered feedback for literate relative to preliterate children was observed, and this was particularly the case for the Dutch children. Moreover, the magnitude of the responses was related to precursors of reading in preliterate children and to reading skill in literate children. We propose that these findings could be related to changes in children’s speech production skills that facilitate the integration of orthographic and phonemic information. [ABSTRACT FROM AUTHOR]

We investigated whether preschoolers with poor phonological awareness (PA) skills had impaired cortical basis for detecting speech feature, and whether speech perception influences future literacy outcomes in preschoolers. We recorded ERP responses to speech in 52 Chinese preschoolers. The results showed that the poor PA group processed speech changes differentially compared to control group in mismatch negativity (MMN) and late discriminative negativity (LDN). Furthermore, speech perception in kindergarten could predict literacy outcomes after literacy acquisition. These suggest that impairment in detecting speech features occurs before formal reading instruction, and that speech perception plays an important role in reading development. [ABSTRACT FROM AUTHOR]

Recent work has suggested that variability in levels of neural activation may be related to behavioral and cognitive performance across a number of domains and may offer information that is not captured by more traditional measures that use the average level of brain activation. We examined the relationship between reading skill in school-aged children and neural activation variability during a functional MRI reading task after taking into account average levels of activity. The reading task involved matching printed and spoken words to pictures of items. Single trial activation estimates were used to calculate the mean and standard deviation of children's responses to print and speech stimuli; multiple regression analyses evaluated the relationship between reading skill and trial-by-trial activation variability. The reliability of observed findings from the discovery sample (n = 44; ages 8-11; 18 female) was then confirmed in an independent sample of children (n = 32; ages 8-11; 14 female). Across the two samples, reading skill was positively related to trial-by-trial variability in the activation response to print in the left inferior frontal gyrus pars triangularis. This relationship held even when accounting for mean levels of activation. This finding suggests that intrasubject variability in trial-by-trial fMRI activation responses to printed words accounts for individual differences in human reading ability that are not fully captured by traditional mean levels of brain activity. Furthermore, this positive relationship between trial-by-trial activation variability and reading skill may provide evidence that neural variability plays a beneficial role during early reading development. [ABSTRACT FROM AUTHOR]

Word learning depends not only on efficient online binding of phonological, orthographic and lexical information, but also on consolidation of new word representations into permanent lexical memory. Work on word learning under a variety of contexts indicates that reading and language skill impact facility of word learning in both print and speech. In addition, recent research finds that individuals with language impairments show deficits in both initial word form learning and in maintaining newly learned representations over time, implicating mechanisms associated with maintenance that may be driven by deficits in overnight consolidation. Although several recent studies have explored the neural bases of overnight consolidation of newly learned words, no extant work has examined individual differences in overnight consolidation at the neural level. The current study addresses this gap in the literature by investigating how individual differences in reading and language skills modulate patterns of neural activation associated with newly learned words following a period of overnight consolidation. Specifically, a community sample of adolescents and young adults with significant variability in reading and oral language (vocabulary) ability were trained on two spoken artificial lexicons, one in the evening on the day before fMRI scanning and one in the morning just prior to scanning. Comparisons of activation between words that were trained and consolidated vs. those that were trained but not consolidated revealed increased cortical activation in a number of language associated and memory associated regions. In addition, individual differences in age, reading skill and vocabulary modulated learning rate in our artificial lexicon learning task and the size of the cortical consolidation effect in the precuneus/posterior cingulate, such that older readers and more skilled readers had larger cortical consolidation effects in this learning-critical region. These findings suggest that age (even into late adolescence) and reading and language skills are important individual differences that affect overnight consolidation of newly learned words. These findings have significant implications for understanding reading and language disorders and should inform pedagogical models. [ABSTRACT FROM AUTHOR]

Background Literacy acquisition is a demanding process that induces significant changes in the brain, especially in the spoken and written language networks. Nevertheless, large-scale paediatric fMRI studies are still limited. Methods We analyzed fMRI data to show how individual differences in reading performance correlate with brain activation for speech and print in 111 children attending kindergarten or first grade and examined group differences between a matched subset of emergent-readers and prereaders. Results Across the entire cohort, individual differences analysis revealed that reading skill was positively correlated with the magnitude of activation difference between words and symbol strings in left superior temporal, inferior frontal and fusiform gyri. Group comparisons of the matched subset of pre- and emergent-readers showed higher activity for emergent-readers in left inferior frontal, precentral, and postcentral gyri. Individual differences in activation for natural versus vocoded speech were also positively correlated with reading skill, primarily in the left temporal cortex. However, in contrast to studies on adult illiterates, group comparisons revealed higher activity in prereaders compared to readers in the frontal lobes. Print-speech coactivation was observed only in readers and individual differences analyses revealed a positive correlation between convergence and reading skill in the left superior temporal sulcus. Conclusions These results emphasise that a child's brain undergoes several modifications to both visual and oral language systems in the process of learning to read. They also suggest that print-speech convergence is a hallmark of acquiring literacy. [ABSTRACT FROM AUTHOR]

The brain-derived neurotrophic factor ( BDNF ) Val 66 Met single nucleotide polymorphism (SNP) has been associated with individual differences in brain structure and function, and cognition. Research on BDNF's influence on brain and cognition has largely been limited to adults, and little is known about the association of this gene, and specifically the Val 66 Met polymorphism, with developing brain structure and emerging cognitive functions in children. We performed a targeted genetic association analysis on cortical thickness, surface area, and subcortical volume in 78 children (ages 6–10) who were Val homozygotes (homozygous Val/Val carriers) or Met carriers (Val/Met, Met/Met) for the Val 66 Met locus using Atlas-based brain segmentation. We observed greater cortical thickness for Val homozygotes in regions supporting declarative memory systems (anterior temporal pole/entorhinal cortex), consistent with adult findings. Met carriers had greater surface area in the prefrontal and parietal cortices and greater cortical thickness in lateral occipital/parietal cortex in contrast to prior adult findings that may relate to performance on cognitive tasks supported by these regions in Met carriers. Finally, we found larger right hippocampal volume in Met carriers, although inconsistent with adult findings (generally reports larger volumes for Val homozygotes), is consistent with a recent finding in children. Gene expression levels vary across different brain regions and across development and our findings highlight the need to consider this developmental change in explorations of BDNF -brain relationships. The impact of the BDNF Val 66 Met polymorphism on the structure of the developing brain therefore reflects regionally-specific developmental changes in BDNF expression and cortical maturation trajectories. [ABSTRACT FROM AUTHOR]

Recent studies have found considerable individual variation in language comprehenders' predictive behaviors, as revealed by their anticipatory eye movements during language comprehension. The current study investigated the relationship between these predictive behaviors and the language and literacy skills of a diverse, community-based sample of young adults. We found that rapid automatized naming (RAN) was a key determinant of comprehenders' prediction ability (e.g., as reflected in predictive eye movements to a white cake on hearing “The boy will eat the white…”). Simultaneously, comprehension-based measures predicted participants' ability to inhibit eye movements to objects that shared features with predictable referents but were implausible completions (e.g., as reflected in eye movements to a white but inedible white car ). These findings suggest that the excitatory and inhibitory mechanisms that support prediction during language processing are closely linked with specific cognitive abilities that support literacy. We show that a self-organizing cognitive architecture captures this pattern of results. [ABSTRACT FROM AUTHOR]

In the current study, we present a novel fMRI protocol in which words, pseudowords, and other word-like stimuli are passively presented in a rapid, sequential fashion. In this “fast” localizer paradigm, items are presented in groups of four; within sets, words are related in orthographic, phonological, and/or semantic properties. We tested this protocol with a group of skilled adult readers ( N =18). Analyses uncovered key regions of the reading network that were sensitive to different component processes at the group level; namely, left fusiform gyrus as well as the pars opercularis subregion of inferior frontal gyrus were sensitive to lexicality; several regions including left precentral gyrus and left supramarginal gyrus were sensitive to spelling-sound consistency; the pars triangularis subregion of inferior frontal gyrus was sensitive to semantic similarity. Additionally, in a number of key brain regions, activation in response to semantically similar words was related to individual differences in reading comprehension outside the scanner. Importantly, these findings are in line with previous investigations of the reading network, yet data were obtained using much less imaging time than comparable paradigms currently available, especially relative to the number of indices of component processes obtained. This feature, combined with the relatively simple nature of the task, renders it appropriate for groups of subjects with a wide range of reading abilities, including children with impairments. [ABSTRACT FROM AUTHOR]

Understanding how genes impact the brain’s functional activation for learning and cognition during development remains limited. We asked whether a common genetic variant in the BDNF gene (the Val66Met polymorphism) modulates neural activation in the young brain during a critical period for the emergence and maturation of the neural circuitry for reading. In animal models, the bdnf variation has been shown to be associated with the structure and function of the developing brain and in humans it has been associated with multiple aspects of cognition, particularly memory, which are relevant for the development of skilled reading. Yet, little is known about the impact of the Val66Met polymorphism on functional brain activation in development, either in animal models or in humans. Here, we examined whether the BDNF Val66Met polymorphism (dbSNP rs6265) is associated with children’s (age 6–10) neural activation patterns during a reading task (n = 81) using functional magnetic resonance imaging (fMRI), genotyping, and standardized behavioral assessments of cognitive and reading development. Children homozygous for the Val allele at the SNP rs6265 of the BDNF gene outperformed Met allele carriers on reading comprehension and phonological memory, tasks that have a strong memory component. Consistent with these behavioral findings, Met allele carriers showed greater activation in reading–related brain regions including the fusiform gyrus, the left inferior frontal gyrus and left superior temporal gyrus as well as greater activation in the hippocampus during a word and pseudoword reading task. Increased engagement of memory and spoken language regions for Met allele carriers relative to Val/Val homozygotes during reading suggests that Met carriers have to exert greater effort required to retrieve phonological codes. [ABSTRACT FROM AUTHOR]

Phonological processing ability is a key factor in reading acquisition, predicting its later success or causing reading problems when it is weakened. Our aim here was to establish the neural correlates of auditory word rhyming (a standard phonological measure) in 102 young children with (FHD +) and without familial history of dyslexia (FHD −) in a shallow orthography (i.e. Polish). Secondly, in order to gain a deeper understanding on how schooling shapes brain activity to phonological awareness, a comparison was made of children who had had formal literacy instruction for several months (in first grade) and those who had not yet had any formal instruction in literacy (in kindergarten). FHD + children compared to FHD − children in the first grade scored lower in an early print task and showed longer reaction times in the in-scanner rhyme task. No behavioral differences between FHD + and FHD − were found in the kindergarten group. On the neuronal level, overall familial risk was associated with reduced activation in the bilateral temporal, tempo-parietal and inferior temporal–occipital regions, as well as the bilateral inferior and middle frontal gyri. Subcortically, hypoactivation was found in the bilateral thalami, caudate, and right putamen in FHD +. A main effect of the children's grade was present only in the left inferior frontal gyrus, where reduced activation for rhyming was shown in first-graders. Several regions in the ventral occipital cortex, including the fusiform gyrus, and in the right middle frontal and postcentral gyri, displayed an interaction between familial risk and grade. The present results show strong influence of familial risk that may actually increase with formal literacy instruction. [ABSTRACT FROM AUTHOR]

Becoming a skilled reader requires building a functional neurocircuitry for printed-language processing that integrates with spoken-language-processing networks. In this longitudinal study, functional MRI (fMRI) was used to examine convergent activation for printed and spoken language (print-speech coactivation) in selected regions implicated in printed-language processing (the reading network). We found that print-speech coactivation across the left-hemisphere reading network in beginning readers predicted reading achievement 2 years later beyond the effects of brain activity for either modality alone; moreover, coactivation effects accounted for variance in later reading after controlling for initial reading performance. Within the reading network, effects of coactivation were significant in bilateral inferior frontal gyrus (IFG) and left inferior parietal cortex and fusiform gyrus. The contribution of left and right IFG differed, with more coactivation in left IFG predicting better achievement but more coactivation in right IFG predicting poorer achievement. Findings point to the centrality of print-speech convergence in building an efficient reading circuitry in children. [ABSTRACT FROM AUTHOR]

We propose and test a theoretical perspective in which a universal hallmark of successful literacy acquisition is the convergence of the speech and orthographic processing systems onto a common network of neural structures, regardless of how spoken words are represented orthographically in a writing system. During functional MRI, skilled adult readers of four distinct and highly contrasting languages, Spanish, English, Hebrew, and Chinese, performed an identical semantic categorization task to spoken and written words. Results from three complementary analytic approaches demonstrate limited language variation, with speech--print convergence emerging as a common brain signature of reading proficiency across the wide spectrum of selected languages, whether their writing system is alphabetic or logographic, whether it is opaque or transparent, and regardless of the phonological and morphological structure it represents. [ABSTRACT FROM AUTHOR]

Despite anecdotal evidence of relative visuospatial processing strengths in individuals with reading disability (RD), only a few studies have assessed the presence or the extent of these putative strengths. The current study examined the cognitive and neural bases of visuospatial processing abilities in adolescents with RD relative to typically developing (TD) peers. Using both cognitive tasks and functional magnetic resonance imaging (fMRI) we contrasted printed word recognition with non-language visuospatial processing tasks. Behaviorally, lower reading skill was related to a visuospatial processing advantage (shorter latencies and equivalent accuracy) on a geometric figure processing task, similar to findings shown in two published studies. FMRI analyses revealed key group by task interactions in patterns of cortical and subcortical activation, particularly in frontostriatal networks, and in the distributions of right and left hemisphere activation on the two tasks. The results are discussed in terms of a possible neural tradeoff in visuospatial processing in RD. [ABSTRACT FROM AUTHOR]

A Correction to this paper has been published: https://doi.org/10.1007/s00247-020-04958-w [ABSTRACT FROM AUTHOR]