ORTHOGRAPHIC AND PHONOLOGICAL SELECTIVITY IN DYSLEXIA: AN FMRI STUDY
F Guinevere
Georgetown Universitycity: Washington country: United States (us)
Grant 5R21HD067884-02 from Eunice Kennedy Shriver National Institute Of Child Health & Human Development
Keywords: Address; Adult; Affect; Area; base; Behavior; Behavioral; Brain; Brain imaging; Brain region; Code; Cognitive; Cognitive deficits; density; design; Developmental reading disorder; Dorsal; Dyslexia; experience; Financial compensation; Functional Magnetic Resonance Imaging; Future; Goals; Hyperactive behavior; imaging modality; Imaging problem; Imaging Techniques; Imaging technology; Impairment; Individual; Inferior frontal gyrus; insight; interest; Intervention; Investigation; Lead; Learning; Left; Link; literate; Measures; Mediating; Methods; Neurons; novel; Orthography; paired stimuli; Parietal; Parietal Lobe; Pathway interactions; Performance; phonology; Physiological; Population; Process; public health relevance; Reader; Reading; Reading Disabilities; Reading Disorder; relating to nervous system; Relative (related person); remediation; Reporting; Research; response; Semantics; Signal Transduction; skills; Societies; Specificity; Stimulus; Stream; System; Techniques; Testing; theories; Time; time use; university student; Visual; Visual Pathways
Relevance: Orthographic and phonological selectivity in dyslexia: an fMRI study Developmental dyslexia is a common (5-12% of the population) reading disability, unexpected in relation to other cognitive abilities and the provision of educational opportunities. A new imaging method will be used to better understand the specificity of the brain circuits involved in reading by comparing dyslexic and non- dyslexic college students. The results will advance our understanding of the mechanisms that lead to disorders of reading and potentially guide future interventions, eventually reducing the number of impaired readers and limiting the detrimental educational and vocational consequences of dyslexia
Project start date: 2011-03-07
Project end date: 2013-01-31
Budget start date: 1-FEB-2012
Budget end date: 31-JAN-2013
5R21HD067884-02 (2012): $190069
Sponsored Links Excellgen http://Excellgen.com
Grants awarded to F Guinevere
ORTHOGRAPHIC AND PHONOLOGICAL SELECTIVITY IN DYSLEXIA: AN FMRI STUDY
F Guinevere, Associate Professor
Georgetown Universitycity: Washington country: United States (us)
Grant 1R21HD067884-01A1 from Eunice Kennedy Shriver National Institute Of Child Health & Human Development
Abstract: Reading is paramount in our literate society; unfortunately it does not come easily to 5-12% of the population who suffer the heritable condition of developmental dyslexia, a reading difficulty unexpected in relation to other cognitive abilities and the provision of educational opportunities. Modern imaging technology has demonstrated that typical readers rely on two left-lateralized pathways A dorsal circuit mediating phonological processing and a ventral, visual pathway, including the "visual word form area", VWFA, specialized for the fast recognition of single words. How these pathways are affected in dyslexia, has been a topic of intense research. Most current theories posit a weakness in phonological processing as the primary problem and imaging studies have revealed physiological and anatomical differences in left parietal cortex when comparing dyslexic and non- dyslexic readers. At the same time, there are many reports of decreased activity in the ventral visual pathway, which represents another important part of the reading system leading to semantic access. The application´s long-term objective is to employ a novel technical approach that will lead to better characterization of the neural bases of both these ventral and dorsal streams and differences in dyslexia. To date, functional magnetic resonance imaging (fMRI) technology has been limited by the fact that the density of selective neurons as well as the broadness of their tuning contributes to the average activity measured. FMRI rapid adaptation (fMRI- RA), however, probes neuronal selectivity more directly and allows a better characterization of neuron-level processing and its link to behavior. This is critical if we are to understand findings about hypo- and hyper- activity reported in various regions of the brain in current studies of dyslexia, as the interpretation of these results has been somewhat limited. Specifically, the project will examine selectivity differences in phonological and orthographic representations in dyslexic relative to typical readers by comparing adults with and without dyslexia. The study will first test the hypothesis that adults with dyslexia who have normal real word reading skills (albeit poor pseudoword reading) show normal selectivity for real words in their VWFA (preserved left VWFA or right VWFA compensation), while those dyslexics with poor real word reading skills do not; and that real word reading ability correlates with selectivity in the VWFA (Aim 1). Secondly, the study will test the hypothesis that adults with dyslexia, due to their weaknesses in phonological coding, show less selectivity for phonological processing in left parietal cortex than typical readers, and that pseudoword reading ability correlates with parietal selectivity (Aim 2). These studies will make it possible, for the first time, to gauge specificity of brain activity in dyslexia rather than simply activation levels. This information is critical if we are to understand the mechanisms that lead to disorders of reading and importantly, guide which interventions should be applied, as current treatments are likely to impact different brain systems. Advancing this field could reduce the number of impaired readers and limit the detrimental educational and vocational consequences of dyslexia. Developmental dyslexia is a common (5-12% of the population) reading disability, unexpected in relation to other cognitive abilities and the provision of educational opportunities. A new imaging method will be used to better understand the specificity of the brain circuits involved in reading by comparing dyslexic and non- dyslexic college students. The results will advance our understanding of the mechanisms that lead to disorders of reading and potentially guide future interventions, eventually reducing the number of impaired readers and limiting the detrimental educational and vocational consequences of dyslexia
Keywords: Address; Adult; Affect; Area; base; Behavior; Behavioral; Brain; Brain imaging; Brain region; Code; Cognitive; Cognitive deficits; density; design; Developmental reading disorder; Dorsal; Dyslexia; experience; Financial compensation; Functional Magnetic Resonance Imaging; Future; Goals; Hyperactive behavior; imaging modality; Imaging problem; Imaging Techniques; Imaging technology; Impairment; Individual; Inferior frontal gyrus; insight; interest; Intervention; Investigation; Lead; Learning; Left; Link; literate; Measures; Mediating; Methods; Neurons; novel; Orthography; paired stimuli; Parietal; Parietal Lobe; Pathway interactions; Performance; phonology; Physiological; Population; Process; public health relevance; Reader; Reading; Reading Disabilities; Reading Disorder; relating to nervous system; Relative (related person); remediation; Reporting; Research; response; Semantics; Signal Transduction; skills; Societies; Specificity; Stimulus; Stream; System; Techniques; Testing; theories; Time; time use; university student; Visual; Visual Pathways
Relevance: Orthographic and phonological selectivity in dyslexia: an fMRI study Developmental dyslexia is a common (5-12% of the population) reading disability, unexpected in relation to other cognitive abilities and the provision of educational opportunities. A new imaging method will be used to better understand the specificity of the brain circuits involved in reading by comparing dyslexic and non- dyslexic college students. The results will advance our understanding of the mechanisms that lead to disorders of reading and potentially guide future interventions, eventually reducing the number of impaired readers and limiting the detrimental educational and vocational consequences of dyslexia
Project start date: 2011-03-07
Project end date: 2013-01-31
Budget start date: 7-MAR-2011
Budget end date: 31-JAN-2012
PFA/PA: PA-10-069
1R21HD067884-01A1 (2011): $228444
A COMPARISON OF THE NEURO-DEVELOPMENTAL BASIS OF READING IN TWO WRITING SYSTEMS
F Guinevere
Georgetown Universitycity: Washington country: United States (us)
Grant 5R01HD056107-04 from Eunice Kennedy Shriver National Institute Of Child Health & Human Development
Abstract: Although successful reading is critical to the educational and social development of children, few studies have explored the neural representation of reading and its constituent cognitive and sensory skills during the early stages of development. We propose a 3-year longitudinal study using fMRI in conjunction with a battery of psychoeducational assessments to investigate the functional neuroanatomy of reading acquisition in typically developing monolingual English speakers from the 1st to 2nd and on to the 3rd grade. In readers of English we predict left fusiform, superior temporal, and inferior frontal gyri activity to be modulated by age. In addition, we will make direct comparisons between these English speakers and monolingual Mandarin Chinese speakers in mainland China at these three time points, to examine the effects of orthography on the brain areas involved in reading acquisition. As alphabetic and logographic writing systems place different demands on phonological, orthographic, morphological and semantic processes, such comparisons will allow us to identify the neural basis of reading that is universal, as well as brain activity specific to each writing system. Adult data suggest that Chinese character processing makes greater demands on bilateral fusiform and left middle frontal gyri, but does not engage left superior temporal gyrus as is typically reported in English speakers. To test for these differences, comparable experimental approaches will be employed in both countries to assess a variety of reading-related behaviors and brain activity subserving these skills. Neural correlates of reading growth will be assessed using tasks that involve word reading and sensorimotor skills. Task-related activity measured during these paradigms will be evaluated using within- and between-group analyses to evaluate the effect of development and orthography, respectively, as well as their interactions. Correlations between task-related activity and performance on behavioral measures, particularly word recognition and rapid naming, will further help delineate the neural correlates of skills that support reading in these different writing systems. The result will provide normative data by which to compare disordered reading. PUBLIC HEALTH RELEVANCE This work will provide novel insight into the neural correlates of normal reading development in different writing systems, as these are essential to the investigation of disorders of reading development
Keywords: Address; Adult; Age; American; Anatomy; Area; Awareness; base; Behavior; behavior measurement; Behavioral; Behavioral Research; Bilateral; Brain; Child; China; Chinese American; Chinese People; Cognitive; comparison group; Country; Data; design; Development; Dorsal; extrastriate; extrastriate visual cortex; Fingers; frontal lobe; Functional Magnetic Resonance Imaging; Fusiform gyrus; Goals; Growth; Health; indexing; Inferior; Inferior frontal gyrus; insight; interest; Investigation; Knowledge; Left; Longitudinal Studies; Measures; Methods; Middle frontal gyrus structure; Modeling; Motion Perception; Motor; Motor Skills; Movement; Names; Nature; Neuroanatomy; neuroimaging; Neurons; novel; Orthography; Outcome; Parietal; Parietal Lobe; Performance; phonology; Physiological; Play; Predictive Value; Process; psychoeducational; Reader; Reading; Reading Disorder; relating to nervous system; Reliance; Reporting; Research; response; Role; semantic processing; sensorimotor system; Sensory; Shapes; Short-Term Memory; Signal Transduction; skills; Social Development; Staging; Stimulus; Superior temporal gyrus; System; Testing; Time; tool; trait; Visual Cortex; Visual Motion; visual motor; Word Processing; Work; Writing
Project start date: 2008-08-15
Project end date: 2013-05-31
Budget start date: 1-JUN-2011
Budget end date: 31-MAY-2012
PFA/PA: PA-07-070
5R01HD056107-04 (2011): $597863