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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]

In both children and adults there is large variability in reading skill, with approximately 5-10% of individuals characterized as having reading disability; these individuals struggle to learn to read despite adequate intelligence and opportunity. Although it is well established that a substantial portion of this variability is attributed to the genetic differences between individuals, specifics of the connections between reading and the genome are not understood. This article presents data that suggest that variation in the COMT gene, which has previously been associated with variation in higher-order cognition, is associated with reading and reading-related skills, at the level of both brain and behavior. In particular, we found that the COMT Val/Met polymorphism at rs4680, which results in the substitution of the ancestral Valine (Val) by Methionine (Met), was associated with better performance on a number of critical reading measures and with patterns of functional neural activation that have been linked to better readers. We argue that this polymorphism, known for its broad effects on cognition, may modulate (likely through frontal lobe function) reading skill. [ABSTRACT FROM AUTHOR]

Purpose: To examine neural response to spoken and printed language in children with speech sound errors (SSE). Method: Functional magnetic resonance imaging was used to compare processing of auditorily and visually presented words and pseudowords in 17 children with SSE, ages 8;6[years;months] through 10;10, with 17 matched controls. Results: When processing spoken words and pseudowords, the SSE group showed less activation than typically speaking controls in left middle temporal gyrus. They also showed greater activation than controls in several cortical and subcortical regions (e.g., left superior temporal gyrus, globus pallidus, insula, fusiform, and bilateral parietal regions). In response to printed words and pseudowords, children with SSE had greater activation than controls in regions including bilateral fusiform and anterior cingulate. Some differences were found in both speech and print processing that that may be associated with children with SSE failing to show common patterns of task-induced deactivation and/or attentional resource allocation. Conclusion: Compared with controls, children with SSE appear to rely more on several dorsal speech perception regions and less on ventral speech perception regions. When processing print, numerous regions were observed to be activated more for the SSE group than for controls. [ABSTRACT FROM AUTHOR]

We provide an illustration of an application of the elastic net to a large number of common genetic variants in the context of the search for the genetic bases of an endophenotype conceivably related to individual differences in learning. GABA concentration in the occipital cortex, a critical area for reading, was obtained in a group ( n = 76) of children aged 6-10 years. Two extreme groups, high and low, were selected for genotyping with the 650Y Illumina array chip (Ilmn650Y). An elastic net approach was applied to the resulting SNP dataset; 100 SNPs were identified for each chromosome as 'interesting' based on having the highest absolute value coefficients. The analyses highlighted chromosomes 15 and 20, which contained 55 candidate genes. The STRING partner analyses of the associated proteins pointed to a number of related genes, most notably, GABA and NTRK receptors. [ABSTRACT FROM AUTHOR]

Using functional magnetic resonance imaging, we investigated multimodal (visual and auditory) semantic and unimodal (visual only) phonological processing in reading disabled (RD) adolescents and non-impaired (NI) control participants. We found reduced activation for RD relative to NI in a number of left-hemisphere reading-related areas across all processing tasks regardless of task type (semantic vs. phonological) or modality (auditory vs. visual modality). Moreover, activation differences in these regions, which included the inferior frontal gyrus, the superior temporal gyrus, and the occipitotemporal region, were largely independent of in-scanner performance in our auditory semantic task. That is, although RD participants and NI participants differed in performance in visually presented conditions, they did not differ significantly in the auditory condition, yet similar patterns of reduced activation were observed in these regions across conditions. These findings indicate a neurobiological marker in RD that is independent of task, modality, or performance. These findings are discussed in the context of current neurobiological models of RD. [ABSTRACT FROM AUTHOR]

Using fMRI, we explored the relationship between phonological awareness (PA), a measure of metaphonological knowledge of the segmental structure of speech, and brain activation patterns during processing of print and speech in young readers from 6 to 10 years of age. Behavioral measures of PA were positively correlated with activation levels for print relative to speech tokens in superior temporal and occipito-temporal regions. Differences between print-elicited activation levels in superior temporal and inferior frontal sites were also correlated with PA measures with the direction of the correlation depending on stimulus type: positive for pronounceable pseudowords and negative for consonant strings. These results support and extend the many indications in the behavioral and neurocognitive literature that PA is a major component of skill in beginning readers and point to a developmental trajectory by which written language engages areas originally shaped by speech for learners on the path toward successful literacy acquisition. [ABSTRACT FROM AUTHOR]

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]

Efficient function of neurocircuitry that supports working memory occurs within a narrow range of dopamine neurotransmission. Work in rodents has shown that exposure to nicotine during adolescence leads to nicotine withdrawal emergent alterations in cortical and subcortical dopamine neurotransmission. To test for evidence that the efficiency of neurocircuitry supporting working memory is altered during acute smoking abstinence in adolescent daily tobacco smokers. Fifty-five adolescent daily tobacco smokers were compared with 38 nonsmokers using functional magnetic resonance imaging while subjects performed a verbal working memory task. Smokers were studied during smoking and after 24 h of abstinence from tobacco use. Performance of a task with high working memory load in the context of smoking abstinence was associated with greater activation of components of the verbal working memory neurocircuit, including left ventrolateral prefrontal cortex and left inferior parietal lobe, among smokers relative to nonsmokers. During smoking abstinence, smokers failed to exhibit increases in functional connectivity between components of the working memory neurocircuit with increasing working memory load observed in nonsmoking adolescents and in prior studies of adults. Smoking abstinence in adolescent smokers is associated with reductions in the efficiency of working memory neurocircuitry and alterations in the functional coordination between components of the working memory neurocircuit. These alterations may stem from effects of nicotine exposure on catecholaminergic systems during adolescent development. [ABSTRACT FROM AUTHOR]

The article examines the potential contributions of reading development and reading disability (RD) from functional neuroimaging in diverse languages and cultures. Through the existing research on RD as a starting point, the authors consider how developmental neuroimaging might be enforced to help discriminate RD readers whose deficits are of a congenital origin from those deficits are primarily environmental, and to offer sensitive neurobiological outcome measures to help examine the efficacy of different approaches to the teaching of the reading.

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.

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.

Reading is a learned activity that engages multiple cognitive systems. In a cohort of typical and struggling adult readers we show evidence that successful oral reading of real words is related to gamma-amino-butyric acid (GABA) concentration in the higher-order language system, whereas reading of unfamiliar pseudo-words is not related to GABA in this system. We also demonstrate the capability of resting state functional connectivity (rsFC) combined with GABA measures to predict single real word compared to pseudo-word reading performance. Results show that the strength of rsFC between left fusiform gyrus (L-FG) and higher-order language systems predicts oral reading behavior of real words, irrespective of the local concentration of GABA. On the other hand, pseudo-words, which require grapheme-to-phoneme conversion, are not predicted by the connection between L-FG and higher-order language system. This suggests that L-FG may have a multi-functional role: lexical processing of real words and grapheme-to-phoneme processing of pseudo-words. Additionally, rsFC between L-FG, pre-motor, and putamen areas are positively related to the oral reading of both real and pseudo-words, suggesting that text may be converted into a phoneme sequence for speech initiation and production regardless of whether the stimulus is a real word or pseudo-word. In summary, from a systems neuroscience perspective, we show that: (i) strong rsFC between higher order visual, language, and pre-motor areas can predict and differentiate efficient oral reading of real and pseudo-words. (ii) GABA measures, along with rsFC, help to further differentiate the neural pathways for previously learned real words versus unfamiliar pseudo-words. [ABSTRACT FROM AUTHOR]

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]

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]

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]

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.