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59Learning about Learning Disabilities 2012 Elsevier Inc.
All rights reserved.2012
Brain and Behavioral Response to Intervention for Specific Reading, Writing, and Math Disabilities: What Works for Whom?Virginia W. Berninger1, and Michael Dunn21University of Washington, Seattle, WA 98195-3600, USA 2Washington State University, Vancouver, WA 98686-9600, USA
Learning about the Brain 60Defining Brain 60Brain Geography 60Brain Imaging Technologies 61Systems Approach 62Working Memory 64Controlled and Automatic Processing 65NatureNurture Interactions 65Comparing Reading, Writing, and Math Brains 66
Brain Differences of Individuals with and without SLDS 66Reading 66Writing 67Math 67
Behavioral and Brain Response to Intervention (RTI) 68RTI as a NatureNurture Perspective 68Behavioral RTI 70Brain Response to Intervention (RTI) 74
Individual, Developmental, Gender, Language, and Cultural Differences 76Longitudinal Studies 76Gender Differences 77Language and Cultural Differences 77Defining SLDs in Reading, Writing, and Math 77
Conclusions and Recommendations 80References 80
Learning about Learning Disabilities60
LEARNING ABOUT THE BRAINDefining BrainThe human brain is a complex electrochemical organ with texture like jello. Weighing only about three pounds, this organ supports an individuals inner mental activity and interactions with the external environment. Brain initi-ates behaviors, and changes in response to environmental events; also, brain and genes in each neuron mediate response to intervention. Thus, brain is an independent variable, dependent variable, and intervening variable, respec-tively (Berninger & Richards, 2009). Understanding the brain requires research on its structures, physiological functions, and behaviors, all of which are interrelated but not in a simple one-to-one way (Mesulam, 1990).
Only the sensory and motor systems have direct contact with the exter-nal world, but these systems create connections with the inner language and/or cognitive systems as well as with each other so that the inner systems can communicate with the external world through the sensory and motor end organs (Berninger & Richards, 2011; Berninger, Fayol, & Alamargot, 2012, Chapter 4, Table 4.4). Four separable functional language systemslanguage by ear (listening), language by mouth (speaking), language by eye (reading), and language by hand (writing)are created which can func-tion alone or in concert (Berninger & Abbott, 2010). Cognitions can be translated into language (Fayol, Alamargot, & Berninger, 2012) or non-language format (Dunn, 2012; also see section on Behavioral RTI, writing in this chapter). Most human cognition exists outside conscious awareness, but with support of working memory can be brought into consciousness for temporary goal-related tasks (Berninger, Rijlaarsdam, & Fayol, 2012, Tables 3.1 through 3.5). Yet, what is probably the most remarkable about the human brain was best captured by a poet, not a neuroscientist, namely, the capacity of the brain to create an inner cognitive world to represent and conduct its own thinking as well as to receive incoming messages from the environment and behave in the environment. In the words of the poet Emily Dickenson (Poem 632 quoted by Diamond (1999, page 38)):
The Brainis wider than the skyForput them side by sideThe one the other will containWith easeand Youbeside.
Brain GeographyOver the years scientists have developed systems for locating brain regions (neuroanatomical structures) in 3-dimensional space and labeling these regions
Brain and Behavioral Response to Intervention for Specific Reading, Writing, and Math Disabilities 61
with names or numbers (e.g., for Brodmanns areas). Neuropsychologists have conducted postmortem studies and more recently brain imaging of living people to identify functions associated with the various specific regions. Books written specifically for educators and psychologists to learn about region- specific brain structures and functions include Berninger and Richards (2002), Blakemore and Frith (2005), and Posner and Rothbart (2007). Technology-supported ways to access and learn the regions and associated functions include (a) Carter et al. (2009, which includes an illustrated book and inter-active CD); (b) for PC users, the Brain Atlas accessed at www.cabiatl.com/mricro/mricro/mricro.html#Installation; and (c) for Mac Users, SPM, which requires metlab, should first be installed and then go to the Brain Atlas at http://en.wikibooks.org/wiki/SPM/Installation_on_Mac_OS_%28Intel%29.
It is important to keep in mind that many illustrations in books label structures on the surface; yet these structures are 3-dimensional and extend below the surface and many other structures exist below the sur-face that are not as easily depicted in 2-dimensional drawings. In addi-tion, brain regions are often reported for layers (slices) of brain images from top-to-bottom, or from right to left, or from back of the brain to the front. To identify specific brain structures or regions of brain activation, it is best to rely on reports by neuroscientists with specialized training and expertise in using a Brain Atlas.
Brain Imaging TechnologiesFor an overview of brain imaging technologies used to study the living human brain, see the Appendix in Blackmore and Frith (2005), introduc-tory material in Carter (2009), or Chapter 3 in Berninger and Richards (2002). In general, studies of specific learning disabilities (SLDs) use non-invasive techniques such as (a) structural (MRI), which constructs via computer programs, visualization of neuroanatomical structures (not pho-tographs of them); (b) functional (fMRI) magnetic resonance imaging of region-specific blood oxygen-level dependent (BOLD) activation, which shows specific brains regions that are using glucose to provide energy for processing; or (c) electrophysiological recordings of event-related potentials (ERPs), which record changes in brain wave activity over time from stim-ulus onset to response. Recently developed new techniques assess (a) both where and when activation occurs during scanning; (b) functional connec-tivity for which regions activate at the same time given a specific brain region source; and (c) structural connectivity of white fiber tracts that con-nect pathways distributed across brain regions (diffusion tensor imaging,
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DTI). In contrast, invasive techniques use radioactively labeled dyes to trace brain activity over time (PET) or radiation (CT scans). Typically insti-tutional review boards (IRB) do not approve use of invasive imaging tech-niques with developing children or youth with or without SLDs.
Systems ApproachA research-supported general principle is that brain function involves both local and global activity. Jackson (1887) startled fellow neurologists by claiming that the brain has multi-level organization. Subsequent research has supported these claims. Brain mechanisms depend (a) on structures and functions in individual neurons, (b) the momentary functional con-nectivity between individual neurons separated by a small space (syn-apse), (c) the pathways consisting of many synapsed neurons distributed across brain regions, and (d) the computations of the six layers of cere-bral cortex that periodically coordinate the brain activity distributed in space and sequenced over time (see Berninger & Richards, 2002, 2011). Also, primary brain regions specialize in uni-modal sensory or motor mes-sages; secondary brain regions specialize in hetero-modal messages, which integrate across sensory input and motor output regions, or between lan-guage regions and a sensory or motor output region; and tertiary brain regions specialize in processing at an abstract level independent of sensory, motor, or sensory-motor codes, for example, in cognitive operations such as thinking.
Luria (1962, 1973), the Russian neuropsychologist, further contributed to understanding of functional brain systems in the working brain with these four insights based on careful clinical observations and assessments:a. Multiple brain regions distributed throughout the brain are involved in
performing a specific function.b. It follows that functional systems for performing a specific task or
function have multiple structural and functional components.c. Different tasks draw on common as well as unique brain regions in the
interrelated pathways.d. Thus, the same brain region may participate in more than one func-
tional system.Minsky (1986), a leading architect of artificial intelligence, talked to neuro-scientists throughout the country, built robots to test computational mod-els, created a model that involved multiple systems or a society of mind, and consulted with a poet to find this metaphor to explain the model to the general public. In the Society of Mind Model, a typical agent in a system
Brain and Behavioral Response to Intervention for Specific Reading, Writing, and Math Disabilities 63
knows its jobto switch other agents or pathways on (excitatory) or off (inhibitory), but is typically unaware of the activities of other agents, even when its activities may exert indirect influences on agents far down the communication loop. Thus, the Society of Mind conceptual frame-work accounts for most human cognition being outside conscious aware-ness. Moreover, the different distributed brain regions are on different temporal scales (momentary time). That