In this chapter, we review research on the cognitive, linguistic, and other learning challenges experienced by adults with learning disabilities and the use of accommodations that facilitate learning. We focus mainly on research with college students because the empirical research base is more comprehensive for them than for other adult learners with learning disabilities. The chapter also includes neurocognitive research that has concentrated mainly on children with learning disabilities, although adolescents and adults have been included in the research to some degree.
The chapter has four parts. Part one begins with a brief overview of learning disabilities before turning to a more specific discussion of reading disabilities, the most prevalent and best studied class of learning disabilities. Most of this research concentrates on the reading and comprehension of words and sentences. We next discuss research on writing and the component skills and processes of writing that challenge those with writing disabilities. Part two presents neurocognitive research on the development of brain structures and functions associated with some of the cognitive and linguistic processes that underlie reading disabilities. We discuss the future implications of this research for adult literacy assessment and instruction and the importance of interdisciplinary research for a better understanding of learning disabilities, specifically, the ways in which genetic, neurobiological, behavioral, and environmental forces interact to affect the typical and atypical development of reading and writing skills. Because neurocognitive research on writing disabilities is in the early stages, we focus mainly on the larger body of research on reading. Part three describes accommodations to facilitate learning for those with learning disabilities. The chapter
concludes with a summary and discussion of research needed to design effective instruction and instructional supports for low-literate adolescents and adults with disabilities who need to further develop their reading and writing skills.
The findings presented here are relevant to instructors of colleges or adult basic and secondary education programs. Yet it is important to recognize that learning disabilities also are a condition defined by legal criteria in the United States, criteria to which secondary and postsecondary institutions must adhere in providing services for students with learning disabilities. The college students identified with learning disabilities who have participated in research have met this legal criterion. In addition, access for accommodating individuals with learning disabilities on standardized tests and instructional settings requires documentation that these legal criteria have been met. As a result, the findings reported in this chapter may be most relevant to adults with similar characteristics. More research of the kind described is needed to characterize a broader range of adults.
Learning disabilities is an umbrella term that encompasses several types of developmental disorders evident as difficulties in learning specific academic or language skills, typically reading, mathematics, oral language communication, writing, and motor performance (e.g., coordination; see American Psychiatric Association, 2000, Diagnostic and Statistical Manual of Mental Disorders, 4th ed.). Learning disabilities have been historically difficult to define in part because they are not a unitary or homogeneous disorder and in part because they have been defined through exclusionary rather than inclusionary criteria. The rationale for an exclusionary definition remains relevant today. The diagnosis of learning disabilities is reserved for individuals with unexpected academic underachievement that cannot be attributed to known causes, such as sensory disorders, general intellectual disability, significant emotional or behavioral disorders, poverty, language differences, or inadequate instruction (Fletcher et al., 2007).
It is important to note that consensus on an evidence-based definition of learning disability has not yet been reached. There is much debate on how to improve definitions and legal criterion setting for the diagnosis and remediation of learning disability. Further research is needed to arrive at an evidence-based definition to guide research and practice.1 Our main focus
1Traditional diagnoses of learning disabilities have depended either on (a) showing a significant discrepancy between reading, writing, or math achievement scores and the scores that would be expected based on the individual’s IQ scores (IQ/achievement discrepancy definitions) or (b) substantial underachievement in an academic area in the context of average or
in this chapter, however, is on the known processing deficits experienced by those with learning, reading, and writing disabilities about which there is broader agreement.
Learning disabilities in adulthood by definition describe individuals as developmentally disordered in learning in comparison to age-expected performance and appropriate instructional opportunities. A diagnosis requires evidence that an individual is substantially limited in major life activities (e.g., reading or writing). If learning disabilities are not diagnosed before adulthood, however, it may be difficult to establish that the individual had access to sufficient high-quality instruction. Social/emotional, cognitive, oral language, and achievement abilities influence individual learning differently across the life span, and the recognition of age-specific markers may be critical to reliable and valid diagnostic decision making appropriate for the adolescent and adult population (Gregg, 2009). Adults can experience a range of learning disabilities that are important to diagnose and attend to as part of literacy instruction.
Although better information is needed about the number of adults in literacy programs with learning disabilities, over one-quarter of adults who attend adult education programs report having a learning disability (Tamassia et al., 2007). The prevalence of learning disabilities for the college-bound population is reported to be approximately 3 to 5 percent of student enrollment (National Center for Education Statistics, 2009; Wagner et al., 2005). Due to variability in eligibility criteria, the adult population with learning disabilities represents a very heterogeneous group of individuals in terms of severity, ability, and background.
Many individuals with learning disabilities do not have access to opportunities to develop and demonstrate their knowledge, with unsettling consequences for their career development and adult income (Gregg, 2009; Rojewski and Gregg, 2011). A total of 14 million undergraduates are enrolled in 2- and 4-year colleges in the United States, and the number is expected to reach 16 million by 2015. Among the U.S. population with learning disabilities, approximately 17 percent will take college entrance
low average intelligence, intact sensory abilities, and adequate instructional opportunities. Recent research findings, however, have a greater focus on other approaches such as response to intervention or differentiated diagnoses based on learning over time (Burns, Appleton, and Stehouwer, 2005; Fletcher, Denton, and Francis, 2005; Fuchs and Fuchs, 2005). There is growing agreement among some researchers that a hybrid model of identification is necessary to the definition of learning disabilities, which includes three criteria: (1) inadequate response to appropriate quality instruction; (2) poor achievement in reading, mathematics, or written expression; and (3) evidence that other factors are not the primary cause of poor achievement (Bradley, Danielson, and Hallahan, 2002; Fletcher et al., 2007). At present, however, there is not conclusive evidence or consensus on any one diagnostic approach to identifying learning disabilities.
exams, but only 4 percent of students who had received special education services in high school were found to be enrolled in a 4-year college or university 3 to 5 years after high school (Wagner et al., 2005, 2007). These figures are substantially lower than those for college-bound students without disabilities. The greatest growth in postsecondary attendance by students with learning disabilities is experienced at 2-year colleges (Wagner et al., 2005). Outcome data pertaining to secondary and postsecondary populations with learning disabilities raise concerns about the equity and quality of educational opportunities for these individuals (National Council on Disability, 2003; Wagner et al., 2005). Adolescents with learning disabilities are more likely to experience substandard postsecondary outcomes compared with their nondisabled peers, as evidenced by high secondary retention and dropout rates (Gregg, 2007; Newman et al., 2009; Weiss and Hechtman, 1993; Young and Browning, 2005), lower postsecondary enrollment and attainment (Stodden, Jones, and Chang, 2002; Wagner et al., 2005), restricted labor force participation (Barkley, 2006), and lower earnings (Cheeseman Day and Newburger, 2002). Several factors that contribute to the negative career outcomes of adolescents and adults with learning disabilities include lower self-esteem and greater susceptibility to the negative impact of socioeconomic background on academic achievement (Wagner et al., 2005) and career attainment (Rojewski and Kim, 2003).
Although behavioral tests are used for assessment and diagnosis, learning disabilities have come to be viewed as brain-based conditions with a pathogenesis that involves hereditary (genetic) factors. In recent years, research on assessment and treatment of learning disabilities has become a magnet for the application of new techniques and paradigms from genetics, basic neuroscience, cognitive science, and cognitive neuroscience. Research to date suggests that it is plausible to assume that the malfunctioning of the brain system that supports reading and its development may be caused by multiple deficiencies in the corresponding genetic machinery that guides early brain development (Grigorenko, 2009). Although understanding the genetic and neurobiological mechanisms that underlie learning difficulties is important to a full and adequate definition of learning disabilities, research on gene-brain-environment interactions is required to understand the complex sets of factors that make learning a challenge for many individuals.
Some 80-90 percent of students with learning disabilities are reported to exhibit significant difficulty with reading (Kavale and Reese, 1992; Lerner, 1989; Lyon et al., 2001). The term reading disability is often used interchangeably with the terms dyslexia, reading disorder, and learning disabilities in reading. Adults with reading disabilities experience lower
reading achievement than what is expected given their age, intelligence, and education. High school students with diagnosed learning disabilities have lower literacy levels than students without disabilities (National Assessment of Educational Progress, 2010). Longitudinal research has shown the persistence of a diagnosed reading disability into adulthood and behavioral and biological validation of the lack of reading fluency in adults with dyslexia across the life span (Bruck, 1990, 1992, 1993; Shaywitz, 2003; Swanson and Hsieh, 2009). As discussed in Chapter 3, there is no consensus on the estimated numbers of adult learners who may have such a reading disability. The estimates range from one-tenth to more than half (Patterson, 2008). In a national survey of adult education programs, 89 percent reported providing services to at least one adult with learning disabilities, although most (62 percent) relied on self-reports. Because only 34 percent of programs reported screening for learning disabilities, it is likely that many adults may have gone unrecognized as having a learning disability, especially older students.
A significant number of college students with learning disabilities demonstrate reading underachievement as a result of their disabilities, influencing both their school and work outcomes (Bruck, 1992; Gregg, 2009; Gregg et al., 2002; Shaywitz et al., 2003). According to data from the National Longitudinal Transitional Study-2, over 50 percent of secondary students performed below the 16th percentile on reading comprehension measures, placing them at the lower 25th percent of the general population (Wagner et al., 2005). These students experience various difficulties with the cognitive and linguistic processes involved in decoding, word identification, reading fluency, and reading comprehension.
The importance of phonological, orthographic, and morphemic awareness to decoding and accurate word identification has been well documented.2 The majority of research on decoding in college students with learning disabilities pertains to specific reading disabilities (dyslexia). The persistence of phonological, orthographic, and morphemic awareness deficits has been repeatedly documented (Bruck, 1993; Gregg et al., 2002; Hatcher, Snowling, and Griffiths, 2002; Holmes and Castles, 2001). However, in the absence of valid diagnostic tools normed on the adult
2Phonological awareness or knowledge refers to awareness of individual speech sounds and the ability to associate speech sounds with print (e.g., ability to identify, discriminate, and isolate phonemes for rhyming or repeating and/or manipulating spoken pseudowords). Orthographic awareness is the visual recognition of letter forms and spelling patterns within words. Morphological awareness is the recognition of morphemes (the smallest meaning units in language) and knowledge of word derivations (create, creation, creative, creator).
population, professionals are left to often infer how executive functioning, working memory, attention, metacognition, and oral language deficits differ across and within the broader range of the adult population with dyslexia. Professionals must retain a healthy degree of skepticism that the inferences drawn from cognitive, oral language, and achievement test batteries are equivalent across populations with and without disabilities until measures are validated for individuals with disabilities (Gregg, 2009).
Studies of college students with reading disabilities (dyslexia) have demonstrated that phonological knowledge predicts skill in decoding (Bruck, 1993; Gregg et al., 2002; Hatcher, Snowling, and Griffiths, 2002). As a group, these students over-rely on spelling-sound information, syllabic information, and context for word recognition. Bruck’s research also documented that among this adult population, phonological awareness continued to be an area of deficit in comparison to their peers. The decoding errors demonstrated by individuals with phonological awareness deficits often represent “phonetically implausible” letter and word choices.
Orthographic awareness (e.g., Vellutino, Scanlon, and Chen, 1994) has not received the attention that phonemic awareness has in the literature, particularly with the college population with learning disabilities (Berninger, 1994; Foorman, 1994; Roberts and Mather, 1997). Yet researchers provide strong evidence that orthographic awareness significantly influences the ability to decode words (Cunningham and Stanovich, 1990; Kim, Taft, and Davis, 2004; Stanovich and West, 1989). Empirical verification supports that orthographic processing is a separate latent construct from phonological processing in the adult population (Carr and Posner, 1994; Eviatar, Ganayim, and Ibrahim, 2004; Gregg et al., 2008; Rumsey et al., 1997a, 1997b). However, as Foorman (1994) notes, “although orthographic and phonological processing can be dissociated statistically, they are conceptually intertwined” (p. 321).
Some college students with reading disabilities (dyslexia) demonstrate problems with both phonemic and orthographic awareness. The decoding errors of individuals demonstrating difficulty specific to orthographic processing usually are “phonetically plausible,” meaning that these readers appear to overrely on their phonological abilities. Such readers may accurately represent the sounds in target words that have direct sound-symbol correspondence (e.g., cat) but may be unable to recall unusual or irregular sequences of letters that cannot be sounded out (e.g., yacht).
Proficiency with phonological, orthographic, and semantic knowledge is essential to learning morphemes (Carlisle, 2004). Much research documents the association between morphological awareness and word reading (Carlisle, 1995, 2000; Carlisle and Stone, 2003; Nagy et al., 1989). Recently, two studies investigating the Hebrew college population with learning disabilities (dyslexia) showed these individuals display specific deficits in
morphological processing and a general metalinguistic deficiency that is not explained by phonological processing (Leikin and Hagit, 2006; Schiff and Raveh, 2006). Yet very little research concentrates on how morphological processing affects word knowledge and word reading in English-speaking adult populations with learning disabilities.
Research with college students with learning disabilities points to several sources of difficulty with reading comprehension. These sources of difficulty include verbal working memory, language disorders, executive function, long-term memory, and metacognition (particularly self-regulation and comprehension monitoring). Several recent studies show the significant role of working memory in reading comprehension proficiency (Berninger et al., 2006; Swanson and Ashbaker, 2000; Swanson and Siegel, 2001; Swanson, Howard, and Saez, 2007). In a recent study of young adults, Berninger et al. (2006) investigated three executive functions of working memory (set shifting, inhibition, and monitoring/updating) and three word forms (phonological, orthographic, and morphological) to determine their relationship to reading comprehension performance. The predictive abilities of these linguistic and cognitive processes were not consistent across reading formats, suggesting the importance of assessment task to diagnostic decision making.
Some students experience difficulty with comprehension because of poor decoding, but for other adolescents and adults with learning disabilities, the core of their reading problem is a receptive language disorder (Cain and Oakhill, 2007; Catts, Adlof, and Ellis, 2006). The relationship between oral language and reading comprehension strengthens as readers mature both in age and ability level. There is strong evidence that language-based declarative knowledge and higher order language processes (e.g., inferencing and comprehension monitoring) relate to adults’ reading comprehension (Floyd et al., in review). Prior knowledge helps with inference making and comprehension monitoring across the life span (Kintsch, 1998; Perfetti, Marron, and Foltz, 1996). Listening comprehension also is important for reading comprehension from ages 9 to 19, further suggesting the importance of higher order language processes, such as inferencing and comprehension monitoring, enabled by prior knowledge. Use of these language processes is common to listening comprehension and reading comprehension tasks (Perfetti, 2007). This finding is consistent with research indicating that oral comprehension places an upper limit on reading comprehension performance for children (Stothard and Hulme, 1996). Together these findings indicate the importance of investigating the influence of oral
language on reading comprehension growth in the college population with learning disabilities and adult literacy learners.
Long-term memory is important to interpreting text. Readers construct a situational model during the process of listening or reading comprehension (Kintsch, 1998).3 Long-term memory is believed to be one of the most critical underlying cognitive processes for creating a situation model because it is needed to (1) link propositions (units of meaning in the form of a statement or question) in the text to what the reader already knows and (2) integrate all of the propositions into a meaningful message or whole (Kintsch, 1998; see Chapter 2). The long-term memory measures on the majority of cognitive tests currently available do not have strong concurrent or construct validity, however, and better measurement tools are needed to assess this important construct in the context of reading instruction.
Many individuals with learning disabilities have difficulty with self-regulation and strategy use, which prevents them from using contextual information fully for comprehending text (Cain, Oakhill, and Elbro, 2002; Cain, Oakhill, and Lemmon, 2004). Difficulties with the strategic use of context cues can be manifest in such problems as using cohesive devices, flexibility with word knowledge (e.g., use of idioms, deciphering ambiguous references), and restricted working-memory processes (e.g., executive, attention).
Comprehension monitoring refers to evaluating one’s ongoing understanding of text and spontaneous use of strategies to clarify inconsistencies or uncertainties and other comprehension problems while reading. Some readers with learning disabilities have significant difficulty detecting inconsistencies in what they read. Researchers suggest that difficulty with comprehension monitoring is often the result of restricted working memory and executive processes. Therefore, simply providing such an individual extra time on a reading task might not be very effective unless the reader is also taught specific cognitive strategies to enhance comprehension monitoring. Individuals with learning disabilities show particular difficulty with acquiring self-regulatory strategies and applying them efficiently (Swanson, Hoskyn, and Lee, 1999; Zimmerman, 2000a, 2000b). Thus, effective instruction in reading comprehension must target not only the acquisition of effective reading strategies but also their flexible application and monitoring.
3Situation model refers to creating representations of the meaning of text derived from both propositions stated explicitly (the textbase) and a large number of inferences that must be filled in using world knowledge (see Chapter 2).
Individuals with learning disabilities often demonstrate difficulties with written expression. Findings from the fields of sociolinguistics, cognitive psychology, and neurolinguistics reveal that certain cognitive processes (e.g., working memory, executive functioning, orthographic awareness) influence specific types of written expression (Berninger and Winn, 2006; McCutchen, 2006; Shanahan, 2006; Torrance and Galbraith, 2006) and so provide information critical to the design of effective intervention and accommodation. Strategic learning relies not only on the cognitive abilities of writers, but also on their experiences, self-efficacy beliefs, and motivation (Pajares and Valiante, 2006). Sociolinguistic research verifies that written expression is influenced by affective, situation, and social variables (Englert, Mariage, and Dunsmore, 2006). Research on all of the processes known to affect writing (cognitive, linguistic, affective, and social) is necessary to effective assessment, intervention, and accommodation of adolescents and adults with learning disabilities.
Handwriting and Spelling
There is a small body of evidence that difficulties with basic writing skills, such as handwriting and spelling, constrain writing development. Poor writers often have difficulties mastering these skills (Graham, 1999). As a result, these skills demand the writers’ attention, diverting resources away from other important aspects of writing, such as sentence construction and content generation. When struggling writers are explicitly taught handwriting and spelling, not only do these skills improve but so do other writing processes, such as output and sentence construction (Berninger et al., 1997, 1998; Graham, Harris, and Fink, 2000; Graham, Harris, and Fink-Chorzempa, 2002).
Handwriting. The term graphomotor skills refers to the cognitive, perceptual, and motor skills that enable a person to write. The three types of graphomotor deficits prevalent in the college population with learning disabilities include symbolic, motor speed, and dyspraxia disorders (Deul, 1992; Gregg, 2009). All three interfere with a writer’s handwriting legibility and writing fluency. Individuals with symbolic graphomotor deficits demonstrate specific phonemic, orthographic, and morphological awareness deficits that interfere primarily with the planning and controlling functions required in handwriting (Berninger and Richards, 2002). A college student with learning disabilities and symbolic graphomotor deficits might produce excellent original drawings but not be able to produce legible handwriting. Visual-verbal production (handwriting) draws on very different neurologi-
cal systems than visual-nonverbal production (pictures). Individuals with dyslexia often demonstrate symbolic graphomotor symptoms, resulting in poor handwriting performance. Since it is often difficult for these individuals to recall the letters or words they want to use in order to express their ideas, legibility and writing fluency become a problem for them. The source of this type of graphomotor disorder is symbolic (Berninger, 1994).
Individuals with motor speed deficits demonstrate problems with the timing and temporal aspects of graphomotor tasks, which also draw on the planning and execution functions of writing. These individuals usually provide legible and accurate handwriting, but the speed to produce the product is very slow (Deul, 1992). Historically, motor speed problems were called clumsiness or limb-kinetic apraxia (Liepmann, 1900).
According to Deul (1992), dyspraxia is the “inability to learn and perform age-appropriate sequences of voluntary movements in the face of preserved coordination, strength, and sensation” (Deul, 1992, p. 264). Unlike writers with more symbolic graphomotor deficits, these individuals demonstrate motor pattern difficulties regardless of whether the symbol is verbal or nonverbal. One of the most distinguishing aspects of dyspraxia is the unusual formation of letters and words. These writers will often print in distinct blocklike symbols, usually in all upper case, display inaccurate spaces between letters and words, and show difficulty with letter formation.
Spelling. Spelling is the ability to represent words in print. Researchers have provided evidence of the regularities and opacities of English orthography itself; the role of morphology in spelling; developmental trajectories; spelling acquisition strategies; cognitive, linguistic, and environmental predictors of spelling; the role of various mental representations of words; the role of implicit memory in spelling; the relation between spelling and other academic skills (e.g., decoding); and possible reasons for spelling underachievement (Coleman et al., 2009; Gregg, 2009). There is a spectrum of spelling competency that depends on a variety of factors (e.g., exposure to print, reading style) unrelated to cognitive and language abilities. Even among college students with learning disabilities with similar levels of reading proficiency, some may be unexpectedly poor spellers (Frith, 1980; Holmes and Castles, 2001).
The persistence of spelling problems for college students with learning disabilities (dyslexia) has been supported by empirical evidence (Bruck, 1993; Gregg et al., 2002; Holmes and Malone, 2004). Some researchers suggest that difficulties with phonemic awareness may be reflected in spelling attempts that lack phonetic plausibility—that is, attempts that, if decoded according to typical grapheme-phoneme conversion rules, do not sound exactly like the target word (Coleman et al., 2009; Holmes and Castles, 2001). Recently, researchers have identified morphological aware-
ness (sometimes called morphophonemic awareness) to be another strong predictor of spelling (e.g., Allyn and Burt, 1998; Gregg, 2009; Holmes and Castles, 2001; Leong, 1999) and an area of weakness in college students with learning disabilities (dyslexia) (Bruck, 1993; Coleman et al., 2009; Deacon, Parrila, and Kirby, 2006; Leong, 1999).
Orthographic awareness, orthographic sensitivity, and orthographic processing are all very important to spelling performance across the life span (e.g., Cunningham, Perry, and Stanovich, 2001; Foorman, 1994; Roberts and Mather, 1997; Stanovich, West, and Cunningham, 1991). As Holmes and Castles (2001) note in relation to college students with learning disabilities, “unexpectedly poor spellers are seen to misspell many words, not because of deficient phonological processing, but because their lexical entries contain inadequately specified word-specific information” (p. 321).
Interestingly, college students with attention deficit hyperactivity disorder (ADHD), while often demonstrating problems with spelling, do not demonstrate the number or types of errors characteristic of their peers with learning disabilities (dyslexia). In a recent study, Coleman and Gregg (2005) counted and categorized spelling mistakes in the impromptu essays composed by 263 young adults. The students without disabilities (n = 90) averaged 2 to 3 errors per 1,000 words, and about 80 percent of their incorrect attempts were judged to be plausible (e.g., airate for aerate). Students with ADHD (n = 44), although they made more errors (about 4 per 1,000 words), achieved a similar plausibility rate. The errors of students with learning disabilities (dyslexia, n = 77) were considerably more frequent (7 per 1,000 words) and less plausible (65 percent). This finding indicates the importance of attending to well-defined subgroups of adults in research to identify the most effective approaches for enhancing adults’ writing skills.
Syntax (Sentence Level)
The term syntax refers to rules in a language for assembling words to form sentences. Syntactic awareness and the ability to produce sentence structures require a writer’s semantic (word usage in context), grammar (e.g., agreement), and mechanical (e.g., application of punctuation and capitalization rules) abilities working in unison. Problems with any one of these features can influence fluency with written syntax. Therefore, during an evaluation, examination of word usage, word agreement, and the mechanics of writing should be conducted and taken into consideration in determining how written syntax is influenced by these features.
Research is limited on the cognitive and linguistic processes that influence the ability of college students with learning disabilities to produce written syntax (Gregg, 2009). Most researchers have relied on frequency counts, such as number of words, sentence length, or number of sentences.
Such indices treat grammatical structures as if they are isolated from words, syntactic structures, and context. Yet research from the field of linguistics, particularly sociolinguistics, shows that the context and function of language use relate to the uses of meaning and structure. The association of word meaning to grammatical structure and structure to words provides information pertinent to the understanding of language and to the ability to design instruction in reading and writing (see Biber, Conrad, and Reppen, 1998, for an in-depth discussion).
Gregg et al. (2002) examined the relationship of words and sentence features in the expository essays of four groups of young adult writers (with learning disabilities, ADHD, learning disabilities + ADHD, and normally achieving). They found that the writers with learning disabilities and ADHD had less varied and complex sentence features than the other groups. Biber identified several features of sentences most associated with sentence complexity in written text. Using these complexity indices, Coleman and Gregg (2005) found that with a group of college students with and without dyslexia, two of Biber’s (1988) sentence features—integrated structures (i.e., nouns, prepositions, and attributive adjectives) and word specificity (i.e., word length and word types)—differentiated the two groups of writers. The writing of the college students with learning disabilities (dyslexia) contained significantly fewer of these features, therefore decreasing the linguistic complexity of their writing samples. Interestingly, Coleman and Gregg (2005) also found that the writers with learning disabilities (dyslexia) had more difficulty with sentence features having to do with time (as a main verb tense, prepositions, and time adverbials), a situation that could be due to the executive and attentional constraints on working memory. Another very distinct feature of the discourse of the writers with learning disabilities (dyslexia) was their overuse of hedges (e.g., at about, something like, more or less, almost, maybe, sort of, kind of, etc.). Such grammatical structures provide less specificity and more ambiguity to the meaning of the text. Underlying word knowledge and word access problems might be contributing to this overuse of hedges.
The development of age-appropriate written syntax skills depends on a number of variables. Foremost among these is oral language development (i.e., receptive and expressive syntax). An adult with an expressive (or receptive-expressive) language disorder will struggle to construct written sentences, just as he or she struggles to construct spoken ones. Of course, this is not to imply that intact oral syntax abilities automatically transfer to writing; oral skills are necessary but not sufficient for writing proficiency. Mastery of a formal writing system requires adequate functioning in other cognitive and social areas as well as extensive instruction in grammar, punctuation, word usage, and other conventions. Print exposure is also important, since familiarity and proficiency with different styles and genres (e.g., expository, narrative, technical) depend on it.
Composition (Text Level)
Text structure refers to the means by which individuals organize their ideas in written discourse. Word and sentence structures, as well as function (purpose), can be very different depending on the chosen mode of writing (e.g., narrative, expository, persuasion). The language one uses in written discourse comprises a structure just as words in a sentence determine a syntactic structure. Researchers examining the written text of adolescents with learning disabilities note that these writers often demonstrate difficulty with metacognitive strategies, such as planning, monitoring, evaluating, and revising (Englert, 1990; Graham and Harris, 1999). Little empirical evidence examining the written composition of the college population with learning disabilities is available, however.
The precise role of working memory in composing text is not clear. Some researchers find that working memory deficits influence written text underachievement (Berninger and Richards, 2002; McCutchen, 2006). Recently, Vanderberg and Swanson (2007) investigated the relationship of working memory to the macrostructure (planning, text structure, revision) and microstructure (grammar, punctuation) of writing. They validated the importance of working memory to both the microstructure and macrostructure of written text, but they also stressed that the writing process is more intricately tied to the attentional components of working memory. Other researchers suggest that long-term memory plays a greater role in the composing of text than working memory (Kintsch, 1998).
Sense of Audience
Current thinking about the writing process envisions writing as a problem-solving task that engages the writer in a dialogue with the reader. Research on composing processes reveals common writing patterns between inexperienced writers and students with a need to develop their basic writing skills. For instance, such students often differ from their higher achieving cohorts in the degree and manner in which they consider their audiences (Rubin and Looney, 1990). Studies show that basic writers have little sense of writing as a rhetorical transaction (Rubin and Looney, 1990). That is, such writers seldom view writing as a means of communication or persuasion; rather, they tend to think infrequently of potential readers and fail to use information about their readers even when it is available to them. The problems experienced with revision and audience awareness are interdependent. Rubin (1984) argues that audience awareness is fundamental to revision; to revise is to step back from the writer’s own subjective understanding of a text and experience it with naïve eyes (Murray, 1978).
To investigate a writer’s sense of audience requires evaluation of the writer’s voice, the writer’s perceptions of the audience, and the context
in which the writing occurred (Gregg et al., 1996). Writer, audience, and context are all involved in the dynamic creation of text, and this leads to choices regarding concepts, vocabulary, style, and text organization. In an effort to evaluate such variables, researchers have identified a number of social cognition skills required for developing sensitivity to audience in written language. These social cognition skills affect content, execution, perspective taking, differentiation of voice, and organization of text (Gregg and McAlexander, 1989; Gregg et al., 1996).
Deficits in any one (or more) of these areas impacts a writer’s ability to identify and remain sensitive to a specific audience. In a study exploring the relationship between sense of audience and learning disabilities among college writers with learning disabilities, Gregg and McAlexander (1989) emphasized that certain types of disorders are more likely to cause problems with sense of audience skills than others. Deficits in perspective-taking, which requires the writer to engage in social inference and to perceive or express various traits in others, often characterize typically developing writers as well.
Writing Fluency (Verbosity)
Fluency is a critical construct to address in the evaluation of writing. Fluency in relation to writing is often referred to as “verbosity” and measured by the length of or number of words in a composition. Gregg et al. (2002) investigated the written discourse complexity of college writers with and without learning disabilities (dyslexia). They found that verbosity (number of words), quality, and vocabulary complexity were significantly correlated. In particular, verbosity and quality could not be viewed as separate constructs but were statistically co-occurring functions. In other words, the number of words produced by writers increased their chances for higher quality scores. A critical finding from this study was that vocabulary and fluency proxies—number of words, number of different words, and number of words with more than two syllables—were the best discriminators between college writers with and without learning disabilities (dyslexia).
There is a growing body of research on neurodevelopmental changes in brain organization and how these changes relate to individual differences in language and reading competencies. The studies have examined changes in both structural organization (i.e., gray and white matter volumes) (Giedd et al., 1997; Hua, Tembe, and Dougherty, 2009) and functional organization (i.e., functional neurocircuits) of the brain for language and reading (Booth et al., 2001; Church et al., 2008; Shaywitz et al., 2003; Turkeltaub
et al., 2003). The focus of the research thus far has been on phonological processing, decoding, or word reading (see Pugh et al., 2010, for a review), with more recent research beginning to examine sentence-level processing and comprehension (Cutting and Scarborough, 2006; Meyler et al., 2008; Rimrodt et al., 2010). As described in Chapter 2, these findings show how the brain organizes with reading experience from childhood to late adolescence for typically developing readers and readers with reading disabilities.
The neurotrajectory involved in reading takes years to develop for children given adequate early exposure. For children and adolescents with reading disabilities, this trajectory appears to be disrupted and is associated with structural and functional differences in brain functioning between children with and without reading disabilities. These brain differences are not necessarily fixed or immutable. Change (neuroplasticity) in neurological patterns has been observed in children and adolescents with reading disabilities as a result of effective intervention. In fact, several recent studies suggest that gains in reading skill following intense reading intervention are associated with a more “normalized” brain organization for reading for young children and that such plasticity is possible into adulthood.
We review this intervention research and studies of differences in brain structure and function between readers with and without reading disabilities because it has the future potential to inform assessment and literacy instruction for adults with disabilities as neurobiological theories of learning and reading and writing development become better explicated (Just and Varma, 2007).
A number of anatomical neuroimaging studies (research that uses magnetic resonance imaging, MRI, to measure gray and white matter volumes across brain regions) have identified structural differences, such as reduced gray matter volume, in the brains of people with reading disabilities. These differences have been found in several of the left hemisphere (LH) regions that functional brain imaging show to be involved in reading, including the temporoparietal and occipitotemporal areas (Brambati et al., 2004; Brown et al., 2001; Eckert et al., 2003; Kronbichler et al., 2008; Silani et al., 2005). Using a recently developed MRI technique known as diffusion tensor imaging (DTI), studies show differences in white matter tracts for those with reading disabilities. Individuals with reading disabilities have atypical white matter development in critical LH pathways linking the major reading areas. This finding suggests reduced myelin in the axonal fibers connecting distributed brain areas that form the reading circuits of the brain (Beaulieu et al., 2005; Keller and Just, 2009; Klingberg et al., 2000; Niogi and McCandliss, 2006).
These reported gray and white matter differences in brain organization of LH posterior regions between typically developing readers and those with a reading disability appear to be associated with underlying language difficulties (Niogi and McCandliss, 2006). It is not known whether these structural differences are a cause or consequence of reading disability. This question requires further study with research that includes prospective longitudinal designs with individuals before they learn to read.
Functional neuroimaging research uses such techniques as functional MRI (fMRI) to measure activation in different parts of the brain while an individual performs cognitive tasks. In studies of this type, both children and adults with reading disability show marked functional differences relative to typically developing readers in the activity generated in major components of the reading circuit (temporoparietal, occipitotemporal, and inferior frontal systems) (Brunswick et al., 1999; Meyler et al., 2008; Paulesu et al., 2001; Pugh et al., 2000; Rumsey et al., 1997b; Salmelin et al., 1996; Shaywitz et al., 1998, 2002; Temple et al., 2003). Individuals with reading disability tend to underactivate both temporoparietal and occipitotemporal regions; this disruption also is evident in reduced functional connectivity (a type of analysis that measures the degree to which brain areas show correlated activation and hence are acting as a functional circuit) (Hampson et al., 2006; Horwitz et al., 1998; Pugh et al., 2000). This atypical functional connectivity of key LH posterior regions in disabled relative to able readers suggests interregional communication difficulties in the left hemisphere. This pattern of reduced posterior activation and connectivity in the left hemisphere associated with reading disability has been observed in a large number of studies with both children and adults with reading disabilities (Pugh et al., 2010). In addition, readers with reading disabilities often show evidence of apparently compensatory responses to their LH posterior dysfunction: an increased functional role for right hemisphere (RH) temporoparietal regions (Sarkari et al., 2002; Shaywitz et al., 1998; Simos et al., 2002b) and increased frontal lobe activation in both right and left hemispheres (Brunswick et al., 1999; Shaywitz et al., 1998, 2003).
Differences in both structural and functional brain organization of LH posterior regions have been consistently observed across neuroimaging studies. It is hypothesized that these differences may reflect genetically based patterns of brain development, a subject of research for many years. Postmortem studies show cortical and subcortical cellular anomalies (ectopias, microgyria, and glial scarring) in the brains of individuals with reading disability (Galaburda et al., 1985). Genetic factors may give rise to these anomalies by way of abnormal neuronal migration during fetal brain development. Using animal models, studies that explore the ways in which these anomalies might impede both brain development and learning have been undertaken (Galaburda et al., 2006). This research holds promise for
identifying critical gene-brain-behavior pathways in reading disabilities, although at present the links to core deficits in reading disability (e.g., phonological processing) are not yet fully understood.
More also needs to be understood about the brain bases of basic computational processes involved in reading. For example, reading depends on such cognitive processes as memory and attention; reading disabilities have been associated with deficits that include limited memory capacity, limited processing speed, and specific problems with learning and memory consolidation. Research to identify how structural and functional differences in reading disability may limit learning and cognitive processes will be important to developing brain-based models of reading and other learning disabilities (see Just and Varma, 2007).
The relative contributions of environmental factors (e.g., inadequate learning opportunities) and genetic factors (and their interaction) to brain differences in reading disabilities are complex and not well understood. Reading difficulties at any age or in any population are the result of a complex mix of congenital (gene-brain-behavior) and environmental factors. It is well known that genetic factors contribute to reading disabilities (Fletcher et al., 2007). The observation that reading difficulties run in families and are evident across generations was reported almost a century ago (Hinshelwood, 1917). It has been estimated that children of a parent with a reading disability face an eight times greater risk of a reading disorder themselves relative to the population as a whole (Pennington and Olson, 2005). Much less is known about the specifics, such as which genes play a role and the ways in which genetic influences occur (e.g., effects on brain development). Currently, the genetics literature contains references to about 20 potential genetic susceptibility loci, which are regions of the genome that have demonstrated a statistically significant linkage to reading disability and typically involve more than one and often hundreds of genes (Schumacher et al., 2007). The literature refers to at least six candidate genes for reading disability, which are genes located in susceptibility loci that have been statistically associated with reading disability, including DYX1C1, KIAA0319, DCDC2, ROBO1, MRPL2, and C2orf3 (Grigorenko and Naples, 2009).
None of these loci or genes, however, has been either fully accepted or fully rejected by the field, and intensive research is ongoing. The information that has contributed to the identification of susceptibility loci and candidate genes for reading disability has been generated by molecular genetics studies of reading and reading-related processes. Unlike heritability and relative risk studies, these studies assume the collection of genetic material (DNA) from blood or saliva samples. More research is needed to fully understand the involvement of these genes with reading, its related processes, and their development.
A portion of the adults who need to develop their literacy skills is likely to have genetically based learning disabilities. A range of other factors, such as inadequate instruction, poverty, cultural and language barriers, and motivation, are likely to contribute substantially to the reading difficulties of low-literate adults. Interdisciplinary research aimed at building gene-brain-behavior models of typical and atypical reading development and understanding how these factors interact with environmental forces has the potential to enhance understanding of the unique challenges in developing reading and writing skills faced by adult learners.
As noted earlier, a growing body of evidence is showing how functional neurocircuits change with reading experience from childhood to late adolescence in typically developing youth and how this development differs in populations with reading disabilities (Booth et al., 2001; Church et al., 2008; Shaywitz et al., 2002; Turkeltaub et al., 2003). In one developmental fMRI study using a cross-sectional design, Shaywitz and colleagues examined changes in functional brain organization in large typically developing and reading disabled cohorts ranging from age 7 through 17 (Shaywitz et al., 2002). A beginning reader, on a successful learning trajectory, appears to employ a widely distributed cortical system for reading-related processing, including the temporoparietal, frontal, and RH posterior areas. As typically developing readers mature, the weighting of the functional neuroanatomy for reading shifts toward a more consolidated “expert” system of activation in the LH occipitotemporal area that is known as the visual word form area (VWFA; Dehaene et al., 2002). This region appears important to the development of fluent reading (see Booth et al., 2001; Church et al., 2008; Turkeltaub et al., 2003, for similar arguments).
A full understanding of individual differences in the development of the brain for reading requires understanding not only change in functional circuits over time but also possible neuroanatomical constraints on learning. Structural imaging techniques (MRI) used to examine changes in gray and white matter volume from early childhood into late adolescence and adulthood show variable increases in white matter and decreases in gray matter volumes as brain regions develop (Giedd et al., 1997; Hua et al., 2009; Sowell et al., 2004). Some regions mature later (e.g., prefrontal cortex associated with executive function and response inhibition), whereas others mature earlier (e.g., basic sensory and motor processing systems).
A priority for research is to examine the ways in which age-related changes in gray and white matter organization affect plasticity and the impact on learning to read at later ages. The trajectory of brain development, both structural and functional, is established over a period of years for typically developing children given adequate early exposure. It is not
clear whether the same patterns of neuronal reorganization would occur at later points in the life span in adults without learning difficulties but who were nevertheless deprived of early opportunities to learn; this question merits research, as it may inform how to think about the challenges to brain plasticity for those learning to read later in life. What is known, however, for both children and adolescents with reading disabilities is that, in the absence of intensive remediation, this neurotrajectory of reading-related brain changes remains disrupted (Brunswick et al., 1999; Hampson et al., 2003; Pugh et al., 2000; Shaywitz et al., 2002, 2003; Simos et al., 2002a).
It will be important to determine whether intensive and evidence-based intervention with those who experience atypical patterns of brain organization can lead to some degree of normalization in the structure or function of LH systems. New research on remediation suggests that a good deal of plasticity from childhood into adulthood may still be expected for those with reading disabilities. Several recent treatment studies indicate that, at least for younger readers, gains in reading skill with systematic and intense reading intervention are associated with a more normalized brain organization for reading. In a recent study using magnetoencepholography to measure brain changes, young children with severe reading difficulties underwent a brief but intensive phonologically based reading remediation program (Simos et al., 2002b). After intervention, significant gains in reading were observed, and the most salient change observed for every individual who received the intervention was a robust increase in the activation of the LH temporoparietal regions of the brain and a moderate decrease in the activation of the compensatory RH temporoparietal regions.
Shaywitz et al. (2004) examined three groups of young children with fMRI and performance indices (average age was 6.5 years at initial testing—Time 1) (Shaywitz et al., 2004). One group of children with reading disabilities received nine months of an intensive experimental reading intervention (treatment group). As described in Blachman et al. (2004), the intervention involved eight months of individualized tutoring in an intensive reading program that emphasized explicit instruction in phonological and orthographic patterns and oral reading of text and included some spelling and writing activities. For the fMRI study, there were two control groups: a control group of normal readers and a control group of readers with reading disabilities who received standard intervention from their community schools. Treatment participants with reading disabilities showed significant gains in reading fluency and comprehension compared with the control group with reading disabilities who received remediation in their schools. When the two reading disabled groups were compared on fMRI scans posttreatment (Time 2), significantly more activation increases in LH posterior reading areas were seen in the treatment group. Direct comparison of activation profiles showed that reading disabled children in the treatment group, but not the reading disabled controls, had reliable
increases in activation in LH reading-related sites. One year after treatment, follow-up fMRI scans showed children with reading disabilities in the treatment group continued to experience patterns of brain region activation that indicated the intervention had an enduring influence on normalizing brain pathways for reading.
In research with somewhat older learners, Temple and colleagues (2003) used fMRI scans to examine the effects of an intervention on the cortical circuitry of a group of 8- to 12-year-old children with reading disabilities. After intervention, increased LH activation was observed, which in turn correlated significantly with increased reading scores. Similarly, in a study of fifth graders, Meyler et al. (2008) found that a phonologically based intervention increased LH temporoparietal activation during sentence reading tasks, indicating that successful remediation of core phonological skills can generalize to more demanding reading contexts. Observed increases in gray matter volume indicated a significant effect on both brain structure and function (Keller and Just, 2009). Structural changes that accompany successful intervention (Keller, Carpenter, and Just, 2001; Meyler et al., 2008) suggest that effective remediation normalizes structural differences observed between those with and without reading disabilities. Interventions with adults are rare, but Eden and colleagues (Eden et al., 2004) reported significant behavioral and neurobiological changes with intensive phonological remediation in adult readers with reading disabilities; they report a pattern of increase in LH posterior activation in adults similar to that observed in studies of children with dyslexia.
The fact that both structural and functional reorganization of LH brain circuitry for reading can occur after effective remediation for both children and adults with reading disabilities is potentially very important. Similar positive outcomes may occur for adult learners who have lacked the extended experiences needed to develop literacy skills, regardless of whether or not they have latent (undiagnosed) reading disabilities. Knowledge of brain-based developmental trajectories from childhood to adulthood, although still incomplete, suggests the patterns of brain activation that might be achieved with effective instruction and remediation of struggling readers. This work also has resulted in the development of neurobiological measures for research that may prove useful for evaluating interventions for adults learning to read for the first time.
Accommodations adjust the manner in which instructional or testing situations are presented so that individuals with documented disabilities can learn and demonstrate their learning in a fair and equitable manner (Gregg, 2009). Accommodations are not a replacement for literacy instruction. Rather, accommodations are adjuncts that remove barriers imposed by
poor reading, writing, or academic learning skills (Moats and Dakin, 2007). Understanding the issues surrounding accommodation practices is critical to grasping the consequences for adolescents and adults with learning disabilities who are not provided access or equal opportunities to fully participate in instruction or demonstrate their knowledge in testing contexts. Lack of access to accommodations can have major negative effects on career development and adult income (Gregg, 2007; Gregg and Banerjee, 2005).
As difficulties with phonological, orthographic, morphologic, and syntactic awareness slow down the process of decoding, extra time becomes a critical accommodation for adolescents or adults with learning disabilities (dyslexia). There is a significant amount of research to support the need for this accommodation for adolescents and adults with learning disabilities (Gregg, 2009; Gregg and Nelson, in press; Shaywitz, 2003).
Emerging technologies are changing the range of literacy skills needed in the worlds of school and work. For the college population with learning disabilities, these technologies offer opportunities to be better prepared for today’s technology-rich schools and workplaces. A wide range of technologies are being used to accommodate learning and work environments for these individuals. In the area of reading, alternative media and the software to access these formats are essential accommodations for college students with learning disabilities. Alt media is a broad term that refers to a variety of formats into which printed text is converted (e.g., audiotaped text, enlarged print, electronic text, Braille).
Regardless of the alt media format, etext is not an effective accommodation for individuals with learning disabilities unless it is used in conjunction with assistive technology software. Optical character recognition (OCR) software is first used to convert scanned or bit-mapped images of text into machine-readable form. The text may then be saved on magnetic media (e.g., hard drives) or on optical media (e.g., CD-ROMs). Text converted by OCR software is then read by text-to-speech (TTS) software. TTS is a type of speech-synthesis application that is used to create a spoken version of etext on a computer or handheld device. TTS can enable the reading of computer display information for an adolescent or adult with learning disabilities, or it may simply be used to augment the reading of a text message. Anderson-Inman and Horney (2007) prefer the term supported etext to refer to the integration of etext with assistive software. An important feature of alt media is its portability. Digital files can be delivered to adolescents or adults via email or Internet portals and used in a variety of electronic and physical environments. Current advancements in technology now allow etext files to be downloaded easily not only to computers,
but also to handheld devices, such as phones, personal digital assistants (PDAs), or MP3 players and to be read through specialized TTS software.
However, much of the TTS software cannot access or integrate with the various social media tools—from text messaging to blogging—that are becoming essential to success in school or the workplace. As colleges and universities are posting lectures on YouTube and many chief executives of major companies are communicating to their employees and customers through blogs and web pages, assistive technology software needs to integrate seamlessly with various forms of social media. The lack of empirical evidence to identify effective technologies to provide adolescents and adults with learning disabilities access to reading online and offline (traditional print-based) is of considerable concern, given the prevalence of low literacy skills among youth and young adults in society.
Reading comprehension problems are more difficult to accommodate than decoding and reading fluency problems. Current technology advancements, however, are providing professionals with more tools than ever before to help college students with functional limitations in reading comprehension. One promising technology software accommodation for reading instruction is embedded etext support: TTS and links to definitions, highlighting, and summaries of text (Gregg and Banerjee, 2005). Many of the embedded supports can significantly help readers with reading comprehension problems. Embedded supports used in combination with etext and TTS software may prove more effective than etext or TTS alone for college readers with learning disabilities. A growing body of research is providing strong validation for the effectiveness of embedded supports in enhancing reading comprehension for students with reading disorders (Anderson-Inman, 2004; Anderson-Inman and Horney, 2007; Anderson-Inman et al., 1994; Horney and Anderson-Inman, 1994, 1999).
A promising technology for enhancing the reading comprehension of at-risk readers is web-based tutors that provide online self-explanation and metacognitive reading strategies. McNamara and her colleagues (McNamara et al., 2007) developed one such program called the Interactive Strategy Training for Active Reading and Thinking (iSTART) and have provided strong research evidence to support its effectiveness. It is a web-based tutoring program designed for adolescents and adults that uses animated agents to teach reading strategies. McNamara and colleagues found iSTART to be most beneficial to at-risk readers. However, at this time, no research is available to support its effectiveness with individuals diagnosed with learning disabilities. Again, the effectiveness of software such as iSTART depends on its ease in successfully integrating with screen readers and other technologies necessary to access the online reading requirements of the program.
Extended time on assignments is a necessary accommodation for many
individuals demonstrating reading comprehension underachievement. Difficulty decoding words, understanding vocabulary, or remaining sensitive to sentence or text structures often slows down the reading process for many adolescents or adults with learning disabilities. In addition, if any strategy or technology (e.g., read-aloud, embedded text) is used as an accommodation to assist the process of reading, extended time will be needed to implement such reading tools.
Accommodation of Handwriting
Very little research is available to guide accommodations for the college population with handwriting disorders. Professionals depend on clinical experience and assessment data in choosing specific accommodations. For all three types of graphomotor disorders (i.e., symbolic, speed, dyspraxia) discussed above, extra time is an essential accommodation. Word processing and various assistive technologies also provide accommodation options appropriate for all types of graphomotor disorders. Traditional assistive technologies used with more severe motor disorders, such as adapted switches, adapted keyboards, and keyboard overlays, have not been well investigated by researchers as to their effectiveness with adult populations with learning disabilities. Although limited in number, studies are available to support the effectiveness of word processing, word prediction software, and voice input (speech to text) for enhancing the legibility and fluency of writing for adult populations (Gregg, 2009). In addition, the need is great for researchers to investigate the usefulness of touch windows and macro software for accommodating the writing of college students with learning disabilities, since these recommendations are often suggested by professionals. With the popularity and accessibility of mobile touch devices (i.e., iPad, iPhone), the application of this technology for accommodating graphomotor disorders may emerge.
Accommodation of Spelling Disorders
Spelling difficulty is a hallmark of college writers with learning disabilities (dyslexia). Although there is evidence to support the effectiveness of assistive technologies in enhancing spelling performance, research on the college population is limited. As with handwriting disorders, extra time is an appropriate accommodation for college students with significant spelling deficits, since they require more time to recall the motor and orthographic patterns necessary to spell words. Word processing also appears to enhance the fluency and spelling of young adult writers with learning disabilities
(Bangert-Downs, 1993; Goldberg, Russell, and Cook, 2003; Hetzroni and Shrieber, 2004; MacArthur, 2006). Research also supports the effectiveness of spell checkers and word prediction programs for enhancing the spelling performance of adolescent writers with learning disabilities (Handley-More et al., 2003). Speech recognition software for dictation has gained some support as a means to enhance the writing of adolescents and adults with spelling, handwriting, and fluency problems (Higgins and Raskind, 1995; MacArthur and Cavalier, 2004; Reece and Cumings, 1996).
Accommodation of Syntax Disorders
The effectiveness of accommodations for the college writer with written syntax disorders has not been well addressed. It is important to investigate the cognitive and linguistic deficits underlying difficulty in producing sentence structures as a guide in selecting specific accommodations (Gregg, 2009). For writers struggling to produce written sentences, extra time and word processing are appropriate accommodations. Students with verbal working memory deficits might be helped by word prediction and outlining/ webbing software. For writers with significant attention or executive functioning deficits, outlining, webbing, and TTS software might be an effective accommodation. Research evidence is available to support TTS software for some students in helping them “hear” word choice errors so that they can make revisions (Higgins and Raskind, 1995; MacArthur, 2006). For students whose difficulty recalling words influences sentence structure production, word prediction software might be recommended. Speech-to-text software is often not as effective for writers demonstrating oral expressive syntax disorders. The technology is currently not advanced enough to deal with the oral hesitations and pronunciation errors often demonstrated by these individuals. Little research evidence exists to support the effectiveness of grammar checks as an accommodation for individuals with written syntax disorders.
Accommodation of Text Structure
A basic but important accommodation for writers experiencing difficulties producing text is the provision of extended time (Gregg et al., 2007; Gregg, 2009). Research confirms that extended time can provide these individuals a means to utilize strategies and technologies for improving their written products. If graphomotor, spelling, or syntax abilities are also areas of deficit for a writer, the accommodations previously discussed would be provided in addition.
Speech synthesis (text-to-speech) and speech recognition (speech-to-text) software have potential for enhancing the production of written text
structure. Although limited research is available to provide evidence of the effectiveness of this software for the college population with learning disabilities, advances in assistive technologies appear promising (MacArthur, 2006). In the future, MP3 players (e.g., iPods) with digital voice recorders have the potential to increase the writing proficiency of college writers with learning disabilities (Banerjee and Gregg, 2009).
The effectiveness of teaching adolescent writers with learning disabilities cognitive strategies to enhance their writing competencies is well documented in the literature (Deshler, Ellis, and Lenz, 1996; Englert, 1990; Englert, Mariage, and Dusmore, 2006; Graham and Harris, 2004; Hallenbeck, 1996). For instance, the Think Sheets advocated by Englert in her Cognitive Strategy Instruction in Writing program can provide useful tools to help many of these writers manage the different aspects of writing (planning, organizing, drafting, editing, and author/reader relationship) (Hallenbeck, 1996). The research on computerized software that provides strategic planning, organization, and revising prompts to adolescent and adult writers with learning disabilities, however, has not provided conclusive evidence for the effectiveness of this software (Bonk and Reynolds, 1992; Reynolds and Bonk, 1996; Rowley, Carsons, and Miller, 1998; Rowley and Meyer, 2003; Zellermayer et al., 1991). MacArthur (2006), in a review of assistive technologies and writing, states that he identified only one study (Sturm and Rankin-Erikson, 2002) that provided evidence for the effectiveness of concept mapping software, despite its common use by professionals working with writers demonstrating writing disorders. This lack of research evidence does not diminish the potential utility of such techniques for enhancing the written text of many writers. Rather, it suggests that professionals must ensure that adequate evidence from a comprehensive evaluation provides strong support for the use of concept mapping software with a writer. With the increasing number of empirical studies in the area of hypermedia and computer-mediated communication, it is likely that new tools will be available in the near future to accommodate struggling writers that cannot be conceptualized today.
Adults can experience a range of learning disabilities that are important to diagnose and attend to as part of literacy instruction. The adult population with learning disabilities represents a very heterogeneous group of individuals in relation to severity of learning disabilities, reading and writing abilities, and background. Reading disabilities are the most prevalent and best studied class of learning disabilities. Most neurocognitive research has concentrated on reading. Most research on learning disabilities in adolescents and adults comes from studies of college students or other adults with
relatively high levels of literacy skill. Less research is available with low-literate adults with reading and writing disabilities. The available research shows that adults experience difficulties with specific cognitive and linguistic processes involved in decoding, fluent reading of words and sentences, and reading comprehension. Students with writing disabilities experience difficulties with handwriting, spelling, syntax, composition, sense of audience, and writing fluency.
Research on the effectiveness of instruction to develop the reading and writing skills of adolescents and adults with learning disabilities is sparse, especially for those with low literacy. A priority for future research is the development of effective instructional practices for these populations. As discussed in Chapter 2, neither the available behavioral nor neurocognitive data suggest that instruction for learners who struggle with reading and writing needs to be categorically different from the instruction that is effective with more typically developing learners. Rather, the instruction that has been effective with younger populations targets specific reading and writing difficulties in the context of reading and writing instruction (instead of using decontextualized approaches directed at changing general cognitive processes, which has been shown to be ineffective). The instruction used with typically developing learners also needs to be adapted for those with disabilities to be more explicit and systematic; provide enhanced supports for the transfer and generalization of skills; provide more opportunities for practice; address maladaptive attributions, which can be particularly important to address for struggling learners; and provide scaffolded and differentiated instruction that targets specific difficulties while continuing to develop all the skills needed for reading and writing development (see principles for struggling readers and writers presented in Chapter 2). Research to test instructional approaches consistent with these principles is needed to address the cognitive and linguistic challenges described in this chapter.
Research on accommodations for college students with learning disabilities has a stronger research base. These findings warrant application and further study with all adolescent and adult learners with disabilities. It is important to identify accommodations to remove barriers imposed by poor reading, writing, or academic learning skills. Lack of access to accommodations for individuals with learning disabilities can have major negative effects on career development and adult income. Accommodations for learning need to be used in conjunction with effective instruction to support the development and assessment of literacy. Future policies and practices pertaining to accommodating learning and work environments for the populations with learning disabilities should be guided by evidence-based research.
Assessment batteries used to diagnose learning disabilities and determine who is qualified to receive accommodations in college settings
measure a range of cognitive processing abilities in adolescents and adults. Although behavioral tests are used for assessment and diagnosis, learning disabilities have come to be viewed as brain-based conditions caused by hereditary (genetic) factors and complex pathways of gene-brain-behavior relationships and their interaction with environment and experience. Modern brain imaging techniques show that both children and adults with reading disabilities show marked differences in brain structure and functions relative to typically developing readers. An important next step will be to test causal relations between these structural and functional anomalies and reading using prospective longitudinal designs. In addition, research is needed to better understand the relative contributions of environment (inadequate learning opportunities) and genetic factors (and their interaction) to the different brain trajectories of those with reading disabilities. Gene-brain-behavior research is needed especially to enhance understanding of the unique challenges faced by older learners.
Neurocognitive research shows the plasticity (change) of brains in response to interventions for struggling readers extends into young adulthood, but studies are needed with older adults to determine if the same patterns of neuronal reorganization would occur later in life in response to instruction. This question is also important to ask for adults without learning difficulties but who were nevertheless deprived of early opportunities to learn. Although still incomplete, research on brain-based developmental trajectories from childhood to adulthood suggests patterns of brain activation and consequently improved literacy performance that might be achieved with effective instruction and remediation of struggling readers. This research also suggests ways of measuring neurobiological change that may be useful in evaluating the effectiveness of interventions for adult learners.
For both reading and writing, extra time, various technological supports, and the teaching of cognitive strategies are accommodations that enhance competencies, although many aspects of reading and writing remain to be addressed in research, such as syntax and reading comprehension. Likewise, most published research on brain differences between typically developing and reading disabled learners focuses on phonological processing, decoding, or word reading, and a better understanding of neurobiological processes involved in disorders of syntax, comprehension, spelling, and writing is needed.
The findings in this chapter must be generalized with caution beyond those adults who have met the legal criteria for learning disabilities to which secondary and postsecondary institutions in the United States must adhere in providing services for students with learning disabilities. More research of the kind described is needed to characterize and determine how best to intervene with a broader range of adults in literacy education.