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7
Learning, Reading, and
Writing Disabilities
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 con-
centrated 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 com-
ponent 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, neurobiologi-
cal, 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 accommoda-
tions to facilitate learning for those with learning disabilities. The chapter
179
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180 IMPROVING ADULT LITERACY INSTRUCTION
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 dis-
abilities. 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
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 defini-
tion 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
1 Traditional diagnoses of learning disabilities have depended either on (a) showing a signifi-
cant 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 defini-
tions) or (b) substantial underachievement in an academic area in the context of average or
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LEARNING, READING, AND WRITING DISABILITIES
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 per-
formance 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 differ-
ently 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 individu-
als in terms of severity, ability, and background.
Many individuals with learning disabilities do not have access to op-
portunities 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.
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182 IMPROVING ADULT LITERACY INSTRUCTION
exams, but only 4 percent of students who had received special educa-
tion 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 dis-
abilities 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 con-
tribute to the negative career outcomes of adolescents and adults with learn-
ing 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, learn-
ing 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 com-
plex sets of factors that make learning a challenge for many individuals.
Reading Disabilities
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
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LEARNING, READING, AND WRITING DISABILITIES
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 As-
sessment of Educational Progress, 2010). Longitudinal research has shown
the persistence of a diagnosed reading disability into adulthood and be-
havioral 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 dis-
abilities, 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 disabil-
ity, especially older students.
A significant number of college students with learning disabilities dem-
onstrate reading underachievement as a result of their disabilities, influenc-
ing 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 cog-
nitive and linguistic processes involved in decoding, word identification,
reading fluency, and reading comprehension.
Decoding
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 aware-
ness 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
2 Phonological 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).
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184 IMPROVING ADULT LITERACY INSTRUCTION
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 dem-
onstrated 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 docu-
mented that among this adult population, phonological awareness con-
tinued 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 phono-
logical 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 conceptu-
ally intertwined” (p. 321).
Some college students with reading disabilities (dyslexia) demonstrate
problems with both phonemic and orthographic awareness. The decod-
ing 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 accu-
rately 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 docu-
ments the association between morphological awareness and word reading
(Carlisle, 1995, 2000; Carlisle and Stone, 2003; Nagy et al., 1989). Re-
cently, two studies investigating the Hebrew college population with learn-
ing disabilities (dyslexia) showed these individuals display specific deficits in
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LEARNING, READING, AND WRITING DISABILITIES
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.
Reading Comprehension
Research with college students with learning disabilities points to sev-
eral 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 abili-
ties 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 dis-
abilities, 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 read-
ers 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 infer-
ence 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 suggest-
ing 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 com-
prehension tasks (Perfetti, 2007). This finding is consistent with research
indicating that oral comprehension places an upper limit on reading com-
prehension performance for children (Stothard and Hulme, 1996). Together
these findings indicate the importance of investigating the influence of oral
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186 IMPROVING ADULT LITERACY INSTRUCTION
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 comprehen-
sion (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 ambigu-
ous references), and restricted working-memory processes (e.g., executive,
attention).
Comprehension monitoring refers to evaluating one’s ongoing under-
standing of text and spontaneous use of strategies to clarify inconsisten-
cies or uncertainties and other comprehension problems while reading.
Some readers with learning disabilities have significant difficulty detect-
ing 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 compre-
hension monitoring. Individuals with learning disabilities show particular
difficulty with acquiring self-regulatory strategies and applying them ef-
ficiently (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 applica-
tion and monitoring.
3 Situation
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).
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LEARNING, READING, AND WRITING DISABILITIES
Writing Disabilities
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 in-
tervention 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 re-
search 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, af-
fective, 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 construc-
tion 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, per-
ceptual, 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 dem-
onstrate 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-
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188 IMPROVING ADULT LITERACY INSTRUCTION
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 individu-
als 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 pro-
vide 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 orthog-
raphy itself; the role of morphology in spelling; developmental trajectories;
spelling acquisition strategies; cognitive, linguistic, and environmental pre-
dictors 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 un-
derachievement (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 research-
ers 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-
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LEARNING, READING, AND WRITING DISABILITIES
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 dis-
order (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 incor-
rect 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, dur-
ing 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 influ-
ence 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.
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identifying critical gene-brain-behavior pathways in reading disabilities,
although at present the links to core deficits in reading disability (e.g., pho-
nological processing) are not yet fully understood.
More also needs to be understood about the brain bases of basic com-
putational 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 differ-
ences 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 fac-
tors. 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 par-
ent 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 read-
ing 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 suscep-
tibility 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 infor-
mation 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 heritabil-
ity 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.
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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.
Brain Plasticity
As noted earlier, a growing body of evidence is showing how functional
neurocircuits change with reading experience from childhood to late ado-
lescence 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 exam-
ined 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 process-
ing, including the temporoparietal, frontal, and RH posterior areas. As
typically developing readers mature, the weighting of the functional neuro-
anatomy 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 learn-
ing. 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 cor-
tex 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 develop-
ment, both structural and functional, is established over a period of years
for typically developing children given adequate early exposure. It is not
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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 organiza-
tion 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 plas-
ticity 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 read-
ing 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 activa-
tion 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 test-
ing—Time 1) (Shaywitz et al., 2004). One group of children with read-
ing 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 phono-
logical 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
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increases in activation in LH reading-related sites. One year after treatment,
follow-up fMRI scans showed children with reading disabilities in the treat-
ment 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 read-
ing 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 phono-
logical 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 ex-
tended 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, al-
though 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 TO SUPPORT LITERACY LEARNING
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 instruc-
tion. Rather, accommodations are adjuncts that remove barriers imposed by
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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 dis-
abilities who are not provided access or equal opportunities to fully partici-
pate 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).
Reading Accommodations
As difficulties with phonological, orthographic, morphologic, and syn-
tactic 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 technolo-
gies 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, en-
larged print, electronic text, Braille).
Regardless of the alt media format, etext is not an effective accom-
modation for individuals with learning disabilities unless it is used in con-
junction 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 con-
verted 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 sup-
ported 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 technol-
ogy now allow etext files to be downloaded easily not only to computers,
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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 inte-
grate 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 advance-
ments, however, are providing professionals with more tools than ever
before to help college students with functional limitations in reading com-
prehension. One promising technology software accommodation for read-
ing 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 compre-
hension 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 Inter-
active 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 re-
quirements of the program.
Extended time on assignments is a necessary accommodation for many
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individuals demonstrating reading comprehension underachievement. Dif-
ficulty 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 accommoda-
tion to assist the process of reading, extended time will be needed to imple-
ment such reading tools.
Writing Accommodations
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 pro-
cessing and various assistive technologies also provide accommodation
options appropriate for all types of graphomotor disorders. Traditional as-
sistive 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 profession-
als. With the popularity and accessibility of mobile touch devices (i.e., iPad,
iPhone), the application of this technology for accommodating graphomo-
tor disorders may emerge.
Accommodation of Spelling Disorders
Spelling difficulty is a hallmark of college writers with learning dis-
abilities (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
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(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 sen-
tence 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 func-
tioning 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 pro-
duction, 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 effective-
ness of grammar checks as an accommodation for individuals with written
syntax disorders.
Accommodation of Text Structure
A basic but important accommodation for writers experiencing difficul-
ties producing text is the provision of extended time (Gregg et al., 2007;
Gregg, 2009). Research confirms that extended time can provide these in-
dividuals 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
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structure. Although limited research is available to provide evidence of the
effectiveness of this software for the college population with learning dis-
abilities, 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 dis-
abilities 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 conclu-
sive 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 accommo-
date struggling writers that cannot be conceptualized today.
SUMMARY AND DIRECTIONS FOR RESEARCH
Adults can experience a range of learning disabilities that are important
to diagnose and attend to as part of literacy instruction. The adult popula-
tion with learning disabilities represents a very heterogeneous group of in-
dividuals 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 adoles-
cents and adults comes from studies of college students or other adults with
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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 linguis-
tic 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 audi-
ence, 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 ef-
fective 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 prin-
ciples 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 dis-
abilities 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. Accommoda-
tions 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 de -
termine who is qualified to receive accommodations in college settings
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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. Mod-
ern brain imaging techniques show that both children and adults with read-
ing 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 (in-
adequate 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 adult-
hood, 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 opportuni-
ties to learn. Although still incomplete, research on brain-based develop-
mental 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 sup-
ports, and the teaching of cognitive strategies are accommodations that en-
hance 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 process-
ing, decoding, or word reading, and a better understanding of neurobio-
logical 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.
