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

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]

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]