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ASSESSMENT OF LEARNING DISABILITIES AND ATTENTION-DEFICIT HYPERACTIVITY/DISORDER IN ADULTS. Robert L. Mapou, Ph.D., A.B.P.P. (CN) William R. Stixrud, Ph.D. and Associates, LLC Silver Spring, MD Departments of Psychiatry and Neurology
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ASSESSMENT OF LEARNING DISABILITIES AND ATTENTION-DEFICIT HYPERACTIVITY/DISORDER IN ADULTS Robert L. Mapou, Ph.D., A.B.P.P. (CN) William R. Stixrud, Ph.D. and Associates, LLC Silver Spring, MD Departments of Psychiatry and Neurology Uniformed Services University of the Health Sciences, Bethesda, MD Department of Neurology (Psychology) Georgetown University School of Medicine, Washington, DC R. L. Mapou, Ph.D., ABPP-CN
CONTACT INFORMATION Robert L. Mapou, Ph.D., ABPP-CN William Stixrud, Ph.D. and Associates, LLC 8720 Georgia Avenue Suite 300 Silver Spring MD 20910 (301) 565-0534 x264 (301) 565-2217 FAX E-mail: rmapou@verizon.net Web: www.stixrud.com R. L. Mapou, Ph.D., ABPP-CN
WHAT IS A DISABILITY?WHAT IS A LEARNING DISABILITY? R. L. Mapou, Ph.D., ABPP-CN
ISSUES TO CONSIDER • Learning disabilities was a conceptual rather than a legal term. • Educational law did not specify degree of disability. • Focus on identification, often by discrepancy only • Focus on service delivery • Educational law did not apply to adults. R. L. Mapou, Ph.D., ABPP-CN
DEFINITION OF A DISABILITY UNDER THE 1990 AMERICANS WITH DISABILITIES ACT • A disability is: • “a physical or mental impairment that substantially limits one or more of the major life activities of [an] individual.” • A person is considered disabled if: • “the individual's important life activities are restricted as to the conditions, manner, or duration under which they can be performed in comparison to most people.” R. L. Mapou, Ph.D., ABPP-CN
THEREFORE . . . NOT ALL DISORDERS WITH IMPAIRMENT ARE DISABILITIES! R. L. Mapou, Ph.D., ABPP-CN
LEARNING DISABILITIES:DEFINITIONS R. L. Mapou, Ph.D., ABPP-CN
CURRENT DEFINITIONS Individuals with Disabilities Education Improvement Act of 2002 (IDEA 2004) National Joint Committee on Learning Disabilities (1981, 1987, 1990) R. L. Mapou, Ph.D., ABPP-CN
PROBLEMS WITH CURRENT DEFINITIONS • Limit areas of impairment to language and academics • Does not consider the brain (IDEA 2004) • Does not recognize that problems occur across the lifespan (IDEA 2004) • Includes acquired disorders, some of which would not be considered LDs in adults (IDEA 2004) • Excludes difficulties related to nonverbal LDs, attention, and executive functioning (NJCLD) R. L. Mapou, Ph.D., ABPP-CN
A NEUROPSYCHOLOGICAL DEFINITION? Rehabilitation Services Administration (1985) A specific learning disability is a disorder in one or more of the central nervous system processes involved in perceiving, understanding, and/or using concepts through verbal (spoken or written) language or nonverbal means. This disorder manifests itself with a deficit in one or more of the following areas: attention, reasoning, processing, memory, communication, reading, writing, spelling, calculation, coordination, social competence, and emotional maturity. R. L. Mapou, Ph.D., ABPP-CN
A PROPOSED NEUROPSYCHOLOGICAL DEFINITIONMapou (In preparation) A learning disability is a neurodevelopmental disorder affecting a specific academic and/or cognitive skill that occurs in the presence of intact skills in most other realms. The specific impairments are presumed to be due to dysfunction of the brain and to have been present since birth, although their impact may not become fully obvious until later in life. R. L. Mapou, Ph.D., ABPP-CN
A PROPOSED NEUROPSYCHOLOGICAL DEFINITIONMapou (In preparation) Although most learning disabilities affect academic skills (reading, writing, mathematics) and the associated underlying neuropsychological functions needed for these skills, a learning disability can also affect specific areas of neuropsychological functioning, including attention, executive functions and problem-solving abilities, spoken language, visuospatial skills, or learning and memory. R. L. Mapou, Ph.D., ABPP-CN
A PROPOSED NEUROPSYCHOLOGICAL DEFINITIONMapou (In preparation) A learning disability substantially limits functioning in one or more aspects of a person’s life (e.g., school, work, home, social). It is not better explained by an acquired neurological disorder that occurs either in childhood or later in life, mental retardation, or a pervasive developmental disorder, It is also not due primarily to cultural factors, psychosocial factors, psychiatric disorder, or lack of education, although it may co-exist with these factors. R. L. Mapou, Ph.D., ABPP-CN
TYPES OF LEARNING DISABILITIESFletcher, et. al (2007); Tsatsanis & Rourke (2008); Wasserstein et al., (2008); Cutting & Denckla (2003); Wasserstein & Denckla (in press) • Reading disability • Word recognition (dyslexia) • Fluency • Comprehension • Mathematics disability (computations and/or problem-solving) • Written language disability (handwriting, spelling, and/or composition) • Nonverbal learning disability • Attention and executive functioning disorder R. L. Mapou, Ph.D., ABPP-CN
RESEARCH:LEARNING DISABILITIES IN ADULTS R. L. Mapou, Ph.D., ABPP-CN
RESEARCH ON ADULT LD • Problems with earlier (and some current) research include small samples, limited test batteries, lack of controls, inappropriate statistical methods, and conclusions based on limited data. • There is no “gold standard” or biological marker for LD diagnosis, and studies define LD differently. • Most neuropsychological research has focused on dyslexia, perhaps because of its high prevalence and being more easily defined. • Most research has used college students or young adults. R. L. Mapou, Ph.D., ABPP-CN
PREVALENCE OF LEARNING DISABILITIESGeneralKatz et al. (2001); Henderson (1999); Horn et al. (1999); Sack et al. (2008) • 3 to 20% in the general population • 20 to 89% of adults enrolled in ABE or GED programs • 2 to 4% of college students, based on surveys in 1996 and 1998 • 2.3% of U.S. medical students were reported to have requested accommodations, of which over 90% were for LDs or ADHD R. L. Mapou, Ph.D., ABPP-CN
PREVALENCE OF LEARNING DISABILITIESSpecificKatz et al. (2001) • 80% of all LDs are estimated to affect reading. • 1 to 6% of LDs are estimated to affect mathematics. • 1 to 10% of LDs are estimated to be nonverbal LDs. • 10% of children in school may have LDs affecting writing. R. L. Mapou, Ph.D., ABPP-CN
NEUROPSYCHOLOGICAL FINDINGSREADING DISABILITIES-CORE DEFICITSBirch & Chase (2004); de Gelder & Vrooman (1996); Elbro, (1998); Hugdahl et al. (1995); Lovrich et al. (1997); Katz et al. (2001); Paulesu et al. (2001); Shaywitz & Shaywitz (2005); Shaywitz et al. (2006) • The core dyslexia deficit is in phonemic processing and phonological awareness, demonstrated through neuropsychological and ERP studies. This is found cross-culturally. R. L. Mapou, Ph.D., ABPP-CN
NEUROPSYCHOLOGICAL FINDINGSREADING DISABILITIES-CORE DEFICITSBirch & Chase (2004); Cirino et al. (2005); Vukovic, et. al (2004) • Support for the double-deficit hypothesis of dyslexia (impairment in phonological awareness/rapid visual naming) has also been demonstrated for adults. However support is weaker, and factors including general processing speed, vocabulary, single-word reading, and reading rate may better account for speeded naming deficits. R. L. Mapou, Ph.D., ABPP-CN
NEUROPSYCHOLOGICAL FINDINGSREADING DISABILITIES-ASSOCIATED DEFICITSKatz et al. (2001); Isaki & Plante (1997); Ransby & Swanson (2003) • Associated deficits have been found in language skills and auditory verbal-attention. • More recent studies have found that naming speed, verbal working memory, vocabulary, listening comprehension, and lexical knowledge contribute independently to reading comprehension, beyond the impact of phonological processing. • Phonological processing may be more important for reading acquisition, rather than for reading comprehension in adults. R. L. Mapou, Ph.D., ABPP-CN
NEUROPSYCHOLOGICAL FINDINGSREADING DISABILITIES-VISUAL DEFICITSBen-Yehudah et al. (2001); Eden & Zeffiro (1998); Graves et al. (1999); Hari et al. (2001); Iles et al. (2000); Vellutino et al. (2004) • Vellutino et al. (2004) have noted that the visual theory of dyslexia has been largely discounted. • However, some individuals with dyslexia show visual psychophysical abnormalities. • Magnocellular pathway deficits • More problems with visual target localization R. L. Mapou, Ph.D., ABPP-CN
NEUROPSYCHOLOGICAL FINDINGSREADING DISABILITIES-QUALITY OF READINGBirch & Chase (2004); Cirino et al. (2005); Shaywitz & Shaywitz (2005); Vukovic et al. (2004) • Dyslexic adults are typically slow, inefficient readers, despite having average decoding and single-word reading skills. • Lack of fluency with words and/or text can affect comprehension. • Timed measures appear most sensitive to reading difficulties in adults. R. L. Mapou, Ph.D., ABPP-CN
NEUROPSYCHOLOGICAL FINDINGSREADING DISABILITIES-QUALITY OF READINGWilson & Leseaux (2001); Simmons & Singleton (2000) • Wilson and Leseaux found that dyslexic college students, although average on reading and spelling measures, scored less well than normal students and showed weaknesses in accuracy and speed of phonological processing. • Simmons and Singleton reported that dyslexic college students have more problems with inferential than with literal reading comprehension. R. L. Mapou, Ph.D., ABPP-CN
NEUROPSYCHOLOGICAL FINDINGSMATHEMATICS DISABILITIESKatz et al. (2001) • Deficits can be found in visuospatial and motor skills, similar to what is found in children. • Although attentional problems can contribute to mathematics disabilities, there is no research on this. R. L. Mapou, Ph.D., ABPP-CN
NEUROPSYCHOLOGICAL FINDINGSMATHEMATICS DISABILITIESGreiffenstein & Baker (2002); Cirino et al. (2002) • The first study found that adults with mathematics LDs had deficits in nonverbal reasoning and constructional skills. • In contrast, the second study of college students referred for LD assessment found that mathematics skills were related to semantic knowledge retrieval and executive functioning, but not to visuospatial skills. R. L. Mapou, Ph.D., ABPP-CN
NEUROPSYCHOLOGICAL FINDINGSMATHEMATICS DISABILITIES Osmon et al. (2006b) • Evidence was found for a double deficit in college students with mathematics disorders. • One group showed spatial impairment. • A second group showed executive functioning impairment. • A group with impairments in both areas had the most impaired math skills. • Right hemisphere impairment was hypothesized. R. L. Mapou, Ph.D., ABPP-CN
NEUROPSYCHOLOGICAL FINDINGSWRITTEN LANGUAGE DISABILITIESConnelly et al. (2006) • College students with dyslexia wrote essays of poorer quality due to writing more slowly, making more spelling errors, and using fewer words than normal students. • They made more spelling errors in their essays than expected based on a separate spelling test. • They also had poorer decoding and shorter listening span • The best predictors of essay quality were handwriting speed and spelling accuracy. R. L. Mapou, Ph.D., ABPP-CN
NEUROPSYCHOLOGICAL FINDINGSWRITTEN LANGUAGE DISABILITIESGregg et al. (2007) • The best predictors of the quality of essay writing in college students with dyslexia were vocabulary complexity, verbosity (length of writing), spelling, and handwriting. • These factors were more important for those with dyslexia than for normal students. • The authors concluded that an inability to write fluently placed students with dyslexia at a disadvantage on timed writing tasks. R. L. Mapou, Ph.D., ABPP-CN
NEUROPSYCHOLOGICAL FINDINGSNONVERBAL LEARNING DISABILITIESRourke et al (1986); Tsatsanis & Rourke (2008); Wasserstein et al. (2008) • There is limited work on adults with nonverbal LDs. • Early work showed neuropsychological deficits similar to those in children, along with social deficits. • Subsequent studies have shown deficits in visuospatial skills, motor skills, complex problem solving, and arithmetic. R. L. Mapou, Ph.D., ABPP-CN
NEUROPSYCHOLOGICAL FINDINGSNONVERBAL LEARNING DISABILITIESKatz et al. (2001); Ahmad et al. (2002); Tsatsanis & Rourke (2008) • Cognitive and social deficits are worse in adults than in children, with the largest differences seen in problem-solving, concept formation, and hypothesis testing. • This contrasts with similar deficits in adults and children with language-based LDs. • Most studies have been cross sectional. R. L. Mapou, Ph.D., ABPP-CN
NEUROPSYCHOLOGICAL FINDINGSNONVERBAL LEARNING DISABILITIESWasserstein et al. (2008) • Conclusions: • Some adults with nonverbal LDs show the traditional deficits, but not all do. • Nonverbal LD may not be a unitary entity. • Poor outcome is not universal. R. L. Mapou, Ph.D., ABPP-CN
NEUROPSYCHOLOGICAL FINDINGSGIFTED ADULTS WITH LEARNING DISABILITIESFerri et al. (1997); Gregg et al. (1996) • There is no neuropsychological research on this issue. • Variability in intellectual and academic profiles have been reported, with differences between gifted and non-gifted adults with LDs. • Caveats: • Variability in test results is the rule rather than the exception (Schretlen et al. 2003). • Everyone has strengths and weaknesses. R. L. Mapou, Ph.D., ABPP-CN
OUTCOME AND EARLY INTERVENTIONINTERACTION BETWEEN GENES AND ENVIRONMENTShaywitz et al. (2006) • Recent longitudinal follow-up studies of adults with dyslexia diagnosed as children found different brain connectivity patterns on fMRI for those who developed good reading skills and those who did not. • The authors concluded that despite a genetic underpinning for dyslexia, having better cognitive skills to start and access to intervention will greatly influence outcome. • This reinforces the need for early intervention. R. L. Mapou, Ph.D., ABPP-CN
CO-OCCURRING DISORDERS AND COMPLICATING FACTORSPSYCHIATRIC DISORDERSCleaver & Whitman (1998); Gregg, et al (1992); Hooper & Olley (1996); Hoy & Manglitz (1996); Katz et al. (2001); Vogel & Forness (1992) • Adults with LDs remain at increased risk for psychosocial and psychiatric difficulties. • This is true for nonverbal LDs, which affect emotional processing, as well as for language-based LDs. R. L. Mapou, Ph.D., ABPP-CN
CO-OCCURRING DISORDERS AND COMPLICATING FACTORSPSYCHIATRIC DISORDERSTsatsanis & Rourke (2008); Mesulam & Weintraub (1983); Greiffenstein & Baker (2002) • Adults with nonverbal LDs are especially vulnerable to internalizing disorders because of the impact on interpersonal skills and everyday functioning. • However, studies differ in the degree of psychosocial impairment, and some individuals have no psychosocial problems. R. L. Mapou, Ph.D., ABPP-CN
DIAGNOSISDISCREPANCY VS. CLINICAL APPROACHESSeigel (1993) • Discrepancy approaches are still mandated by many states. • Yet, it is clear that such an approach is not useful and is outdated, given research on learning disabilities and, especially, dyslexia. • Assumptions about the usefulness of discrepancy approaches are often based on clinical lore rather than research. R. L. Mapou, Ph.D., ABPP-CN
DIAGNOSISDISCREPANCY VS. CLINICAL APPROACHESFletcher et al. (2007) • Multiple factors contribute to underachievement: • Emotional and behavioral difficulties • Socioeconomic factors • Inadequate instruction • Response to instruction should be used to assess the possibility of an LD, provided that instruction is shown to be adequate. R. L. Mapou, Ph.D., ABPP-CN
DIAGNOSISDISCREPANCY VS. CLINICAL APPROACHESMapou (in preparation: Brackett & McPherson (1996); Hoy et al. (1996) • Fletcher et al.’s approach has not been used with adults. • There is no research on response to intervention with adults. • Earlier, but limited research indicated that a comprehensive, clinical approach is more effective with adults than a discrepancy approach. R. L. Mapou, Ph.D., ABPP-CN
DIAGNOSISDISCREPANCY VS. CLINICAL APPROACHESMapou (In preparation); Wolf et al. (2008) • Conclusions: • Discrepancy approaches should not be used as the basis for learning disability diagnosis. • Although selective assessment and/or response-to-intervention have empirical support with children, there is no research basis for these approaches in adults. • Comprehensive assessment, including a consideration of demographic, historical, emotional/behavioral, and neuropsychological factors, currently has the most support for assessment of learning disabilities in adults. R. L. Mapou, Ph.D., ABPP-CN
ASSESSMENT OF MOTIVATION AND EFFORTOsmon et al. (2006a) • In an analog study, a new computerized forced-choice measure of reading/word matching, the Word Reading Test, has shown promise for identifying individuals feigning deficits of reading skill or speed. • A double dissociation was found between those asked to feign a reading deficit vs. a speed deficit. • The Word Memory Test also was sensitive, but less so. • Clinical studies remain to be completed. R. L. Mapou, Ph.D., ABPP-CN
ASSESSMENT OF MOTIVATION AND EFFORTDombroski et al. (2006); Lu et al. (2004) • In the context of personal injury litigation, Lu et al. reported that showing a normal interference effect on the Stroop Test identified individuals faking illiteracy. • This could potentially be used to identify feigned reading disorders. • In contrast, Dombroski et al. found that the Rarely Missed Index did not show sensitivity to simulated LD, despite sensitivity to effort in those with TBI. R. L. Mapou, Ph.D., ABPP-CN
ASSESSMENT OF MOTIVATION AND EFFORTAlfano & Boone (2007) • Preliminary data found that individuals diagnosed with LDs did not fail symptom validity measures, based on the presence of LDs alone. R. L. Mapou, Ph.D., ABPP-CN
ASSESSMENT OF MOTIVATION AND EFFORTSullivan et al. (2007) • A study of consecutive referrals for LD/ADHD evaluation in a college assessment center found that 15.4% of those seeking LD evaluation and 9.4% of those seeking LD/ADHD evaluation failed the Word Memory Test, based on Green’s (2003) cutoffs. • This was much lower than the failure rate for those seeking ADHD evaluation. • It was concluded that either secondary gain was less of an issue for LD diagnosis or else the WMT was not sensitive to this. R. L. Mapou, Ph.D., ABPP-CN
ADULT INTERVENTIONSPECIFIC INTERVENTIONSShaywitz (2003); Shaywitz & Shaywitz, (2005); Shaywitz et al. (2006) • Shaywitz and colleagues have described evidence-based programs for improving reading skills in children and adults with dyslexia. • Nonetheless, studies with adults are still in their infancy. • It is clear that intervention should occur as early as possible. R. L. Mapou, Ph.D., ABPP-CN
ADULT INTERVENTIONSPECIFIC INTERVENTIONSEden et al. (2004); Katz et al. (2001) • Eden et al. showed that improvement resulting from a phonologically-targeted training program for adults with dyslexia, which led to improvement in everyday reading skills, was associated with changes on fMRI in brain regions important for reading. • No research has shown efficacy of programs to remediate specific deficits in other LDs, and Katz et al. reported that little work has examined the efficacy of compensatory strategies outside the educational setting. R. L. Mapou, Ph.D., ABPP-CN
ADULT INTERVENTIONACCOMMODATIONS-EXTENDED TIMEShaywitz & Shaywitz (2005); Ofiesh & Hughes (2002) • Extended time on classroom tests is the most common academic accommodation requested for post-secondary education students. • Shaywitz & Shaywitz consider it “essential.” • A review of seven studies by Ofiesh and Hughes showed that additional time used ranged from 50% to double time. Factors that affected the decision about how much time to use included educational setting, the student’s limitations, and the test characteristics. R. L. Mapou, Ph.D., ABPP-CN
ADULT INTERVENTIONACCOMMODATIONS-EXTENDED TIMEAlster (1997); Leadbetter et al. (2001); Runyan (1991); Ofiesh et al. (2005) • Several studies have shown that extended time helps those with LDs in reading or math, but does not help normal learners. • Ofiesh et al. found that the best predictors of the need for extended time in college students were simple timed academic tasks (i.e., WJ3ACH Academic Fluency) rather than timed neuropsychological tasks (i.e., WAIS-III Processing Speed). R. L. Mapou, Ph.D., ABPP-CN
ADULT INTERVENTIONACCOMMODATIONS-COURSE SUBSTITUTIONDowney et al. (2000) • College students with dyslexia performed less well than normal students on measures of foreign language aptitude, single-word reading, spelling, and phonological analysis, but did not differ on timed reading comprehension or single-word repetition. • However, they did not differ from normal students in final grades or final scores on a translation proficiency test in a modified foreign language class. • Courses taught by “master instructors” • Slower pace of instruction • Highly structured and predictable course content • Required daily amount of study time • Use of tutors as needed. R. L. Mapou, Ph.D., ABPP-CN
ADULT INTERVENTIONACCOMMODATIONS-COURSE SUBSTITUTION Sparks et al. (2003) • In contrast, these authors found that college students with LDs seeking foreign language exemption did not differ in language skills, academic skills, or GPA from those who did not seek exemption. • A mediating factor appeared to be overall aptitude, as measured by ACT scores. • Those seeking exemption had done less well in foreign language classes and often sought first time LD evaluation because of this. • LD documentation was often inadequate. • The authors concluded that requests for foreign language substitution should be carefully reviewed, especially if based on a new LD diagnosis. R. L. Mapou, Ph.D., ABPP-CN