DYSLEXIA, DYSGRAPHIA, AND ADHD

Carol Wilkinson, Jessica Witkowski, and Jenna Klotz Development and Behavioral Pediatrics September 11, 2012 Dyslexia

¨ Definion ¤ Characterized by difficules with accurate word recognion, poor spelling and decoding abilies n Must not be due to inadequate instrucon n Must occur in context of normal cognive funconing ¨ A neurobiological condion Background

¨ Most common learning disability ¤ Boys > girls ¨ Risk factors ¤ Family history ¤ History of SLI ¤ Environmental: low exposure to books and instrucon in pre-reading skills, poverty, low parental educaon.

•Recognizes leers and words •Form assoc. with leers that co-occur •Allows for recognion of words that don’t follow typical leer-sound correspondence (i.e. yacht) •Facilitates •Understanding of text understanding of being read meaning of words as •Uses syntax, semanc, they are read and pragmac knowledge •Forms associaons of words/syllables with sounds (phonemes) •Back up the larger system (used to “sound out” an unknown word) Phonological deficit hypothesis

¨ Lack of phonemic awareness blocks access to higher order process involved in comprehension. ¤ Several studies have shown children with dyslexia are impaired in phonological processing tasks n Example: Children with dyslexia and normal readers were compared with reading one and two-syllable nonwords n Dyslexics made more errors in reading nonwords aloud, especially with phonological complexity (p < 0.05)

Neurobiology

¨ Disrupon of le hemisphere posterior brain systems ¨ Study of 24 dyslexic children and 15 normal reading children ¤ Asked to press a buon when 2 visually presented leers rhymed (ie D and T) and then when 2 leers were the same (D and D) n By comparing, can determine which brain acvity was due to phonological demands (rhyme task) vs. orthographic (same leers) ¤ Asked to press a buon when 2 leers matched and then when 2 lines had the same orientaon (ie I and I) n To determine brain acvity due to orthographic processing

Behavioral Results

¨ Dyslexic children were less accurate for rhyme leers (p = 0.05) ¨ No difference between groups for match leers or match lines (p > 0.1) ¨ Performance on rhyme task correlated with reading for all subjects (p = 0.005) Rhyme vs. Leer Matching

¨ Both groups showed acvaon of le frontal lobe with leer match

¨ Normal reading children show le temporo-parietal regions with rhyming

¨ Dyslexic children showed no acvaon of le temporo- parietal cortex with rhyming

¨ Le temporo-parietal region not acvated in leer match task ¤ Deficit is phonological Leer Match vs. Line Match

¨ Several regions showed greater acvity in normal reading children

¨ Dyslexic children did not show acvity in the occipital- parietal area (p=0.02)

¨ Difference in orthographic processing for dyslexia children References

¨ Grizzle, Kenneth L. “Language and Learning: A Discussion of Typical and Disordered Development.” Current Problems in Pediatric and Adolescent Health Care. Vol 39 (7) Aug. 2009, 168-189. ¨ Hamilton, Suon. “Normal Reading Development and Eology of Reading Difficulty in Children.” UpToDate. ¨ Peterson, Robin L. “Neuropsychology and Genecs of Speech, Language, and Literacy Disorders.” Pediatric Clinics of North America. Vol 54 (3). June 2007. 543-561. ¨ Snowling, Margaret J. “Phonemic Deficits in Developmental Dyslexia.” Psychological Research. Vol 43. 1981. 219-234. ¨ Temple, Elise. “Disrupted Neural Responses to Phonological and Orthographc Processing in Dyslexic Children: an fMRI study.” Neuroreport. Vol 12 (2), Feb 2001. 299-307 Developmental Dysgraphia

¨ Wring skills below those expected for a person’s age or ability, despite appropriate educaon ¨ Illegible handwring, leer shape distorons, dysfluent wring, spelling errors or other difficulty in wrien expression that cannot be aributed to disabilies in reading, oral expression, intellectual disability, impaired vision or hearing, or other neurological disorders Developmental Dysgraphia

¨ 10-30% with “difficulty” v. 2-4% with “disability” ¤ Must significantly impair academic achievement and/or ADLs ¨ Rarely resolves without intervenon Purcell et al. Written production ALE meta-analysis

emission tomography (PET) and functional magnetic resonance lexicon), phoneme–grapheme (PG) conversion, and orthographic imaging (fMRI) studies of word spelling in alphabetic language working memory (the graphemic buffer). O-LTM is the store of involving adult participants. the word spellings that an individual is familiar with. As indicated Producing written words involves a number of interacting in Figure 1,information in O-LTM may be retrieved on the basis of cognitive processes that have been described in various models a word’s meaning or, according to some researchers, directly from of written language production (Roeltgen and Heilman, 1985; a representation of the word’s sound (Patterson, 1986). In addi- Rapp and Caramazza, 1997; Rapcsak and Beeson, 2002; Hillis and tion to retrieval from O-LTM, word spellings may be assembled Rapp, 2004). Although these cognitive processes are highly inte- from a phonological stimulus via the PG conversion processes that grated, an important distinction is often made between central apply learned information regarding the relationships between and peripheral components (see Figure 1). The different patterns sounds and letters (or other sub-lexical units) to generate plausi- of impairment that have been observed in cases of acquired dys- ble spellings for sound strings. For example, the sound stimulus graphia subsequent to brain lesions have constituted the major “wuns” could result in the retrieval of the information O-N-C-E source of empirical support for the distinctions between central from O-LTM and/or in the assembly of a plausible spelling such and peripheral processing components as well as for the more fine- as W-U-N-S-E from the PG conversion system. The letter rep- grained distinctions described below and depicted in Figure 1.In resentations assembled or retrieved are assumed to be abstract, addition, convergent evidence for many of these distinctions has lacking format-specific information (such as shape, size, motor been confirmed by behavioral studies of spelling and writing in plan, etc.). The abstract letter strings are then processed by O- neurologically healthy participants. While it is outside the scope WM, a limited capacity system responsible for maintaining letter of this paper to review these literatures, we refer the interested identity and order information active so that they can be selected reader to various reviews (Ellis, 1979; Burt and Fury, 2000; Burt for further processing by peripheral components (Rapp and Kong, and Tate, 2002; Weingarten, 2005). 2002; Kan et al., 2006). These central processes interact with one Spelling typically begins by hearing words (e.g., taking notes another, with evidence specifically supporting bi-directional inter- in a lecture, a message over the phone, etc.) or with inter- actions between O-WM and O-LTM (McCloskey et al., 2006) nally generated word meanings (e.g., writing a letter, a gro- and between O-LTM and PG conversion processes (Rapp et al., cery list, etc.). These auditory comprehension and semantic 2002). processes and mechanisms are not specific to spelling, yet In terms of peripheral processes, it is generally assumed that serve as the basis for the subsequent retrieval or assembly of there are multiple stages involved in going from the abstract letters spellings.Neural Basis of Wrien Expression Spelling-specific, central processes are usually identified representations in O-WM to the correct ordering and execution as: orthographic long-term memory (O-LTM; the orthographic of the effector-specific muscle movements required for expressing

FIGURE 1 | A schematic depiction of the cognitive architecture of the written word production system. Purcell et al., 2011

Frontiers in Psychology | Language Sciences October 2011 | Volume 2 | Article 239 | 2 “Central” Processing

Orthographic working memory

Long term Phoneme to Long term orthographic grapheme orthographic memory conversion memory (retrieval) (storage) “Peripheral” Processing

Sequence of Conversion of motor graphemic commands representaon to motor commands Types of Dysgraphia

Linguisc Dysgraphias Features Can not convert phoneme à grapheme, Phonological but can copy leers. Phonologically incorrect misspelled words. Can not learn or recall lexically (recognize Lexical full words). Misspells words, but phonologically correct. Can not convert grapheme à grapheme. Dyslexic Misspellings with reversals, omissions, inversions, non-words. Fluent incomprehensible order of leers Gerstmann and words. Misspellings with jumbled sequences. Types of Dysgraphia

Non-linguisc Features Dysgraphias Poor penmanship. Motor Apraxic Undy wring with mild reversals. Can copy wring examples, but can not Ideaonal Apraxic write spontaneously. Visuospaal difficulty. Construconal Apraxic Reversals and inversions. Can not copy wring examples. Diagnosing Dysgraphia

¨ Many cases may go unrecognized as these children are frequently viewed as lazy or non-compliant ¨ Standardized spelling tests ¤ Lexical errors: omission of silent leers (whether à wether) ¤ Semanc errors: homonyms (knight à night) ¤ Visuo-spaal errors: deflecons from line ¤ Graphemic/motor errors: fluency of wring ¨ Should also include numbers, copying reading samples appropriate for developmental age

Intervenons for Dysgraphia

¨ Intensive remediaon in handwring directed at specific deficit or learning disability ¨ Combinaon therapy: i.e. focusing on both handwring and story-wring ¨ Bypass strategies ¤ Keyboarding ¤ Photocopied worksheets ¤ Oral test taking Dysgraphia Summary

¨ Difficulty/disability in wrien expression which impairs academics and ADLs ¨ Affects up to 30% of school-aged children ¨ Due to deficits in linguisc learning, working memory, and motor planning ¨ Intervenons should either target or bypass those deficits References

¨ Adi-Japha E, Landau YE, Frenkel L, Teicher M, Gross-Tsur V, Shalev RS. ADHD and Dysgraphia: Underlying Mechanisms. Cortex, 2007. 43:700-709. ¨ Feder KP and Majnemer A. Handwring development, competency, and intervenon. Developmental Medicine & Child Neurology. 2007. 49:312-317. ¨ Gubbay SS and de Klerk NH. A study and review of developmental dysgraphia in relaon to acquired dysgraphia. Brain & Development. 1995. 17:1-8. ¨ Molfese V, Molfese D, Molnar A, Beswick J. Developmental Dyslexia and Dysgraphia. ¨ Purcell JJ, Turkeltaub PE, Eden GF, Rapp B. Examining the central and peripheral processes of wrien word producon through meta-analysis. Froners in Psychology. 2011. ¨ Zoccolo P and Friedmann N. From dyslexia to dyslexias, from dysgraphia to dysgraphias, from a cause to causes: A look at current research on developmental dyslexia and dysgraphia. Cortex. 2010. 46:1211-1215.

ADHD Comorbidies

¨ Opposional defiant disorder ¨ Conduct disorder ¨ Anxiety ¨ Depression ¨ Dyslexia ¨ Wrien Language Disorder ADHD and Dyslexia ADHD and Dyslexia

18-45% of children with ADHD have dyslexia

18-42% of children with dyslexia have ADHD

Germano, Gagliano and Curatolo 2010 3 Hypotheses

¨ Phenocopy hypothesis ¤ “I can’t read easily, so I’m distracted…can I go to the bathroom?”

¨ Shared Aelogy hypothesis ¤ ”Some of the genes that make it hard for me to focus also make it hard for me to understand phonemes.”

¨ Cognive subtype hypothesis ¤ “I’m an individual and my ADHD/dyslexia is not the same as Jonny’s ADHD or Sally’s dyslexia.” Research for genec influence

Both Dyslexia and ADHD are heritable.

Targeted linkage studies have found 9 chromosome regions for dyslexia suscepbility

Treatment of ADHD and Dyslexia

¨ Methylphenidate improves reading performance in children with ADHD and comorbid dyslexia n Bental B and Tirosh E. J. Clin Psychopharm. 2008 n Keulers et al. Eur J Paediatr Neurol 2007 ¨ fMRI of ADHD and RD teens both show decreased acvaon of le striatum and improvement with MPH. n Shafritz et al. Am J Psychiatry 2004

ADHD and Wrien Language Disorders (WLD)

¨ DSM-IV: disorder of wrien expression. ¤ Grammacal/punctuaon ¤ Poor paragraph organizaon ¤ Spelling Errors ¤ Poor handwring

Incidence of ADHD and WLD

¨ Children born between 1976-1982 in Rochester Minnesota ¨ Data from Rochester Epidemiology Project, school district records and 1 private tutoring agency ¨ 5718 children ¤ 2956 boys, 2762 girls ¤ 1509 children with complete assessment data Cummulave Incidence

16.5%

9.4% Cumulave Incidence

No ADHD vs ADHD 16.5% 64.5%

9.4% 57.0%

Distribuon of WLD with RD Distribuon of WLD w/o RD What type of dysgraphia?

• 40 right handed 6th grade boys • ages 11-13 • Normal IWQ, normal reading • ADHD combined type vs non-ADHD What type of dysgraphia?

• Morphological spelling errors: house vs horse • Graphemic errors (motor programming) • Motor kinemac abnormalies: increased pressure, poor me ulizaon, inconsistent shapes/heights NON_LINGUISTIC DYSGRAPHIA Summary

¨ Clear increased incidence of Dyslexia and Dysgraphia in children with ADHD. ¨ Ongoing research into possible genes that affect both ADHD and Dyslexia ¨ Dysgraphia likely non-linguisc, associated with problems in motor programming and kinemac motor producon References

¨ Germano E, Gagliano A, Curatolo P. Comorbidity of ADHD and Dyslexia. Developmental Neuropsychology, 2010, 35(5): 475-493.

¨ Yoshimasu K, Barbaresi WJ, Colligan RC, Killian JM, Voight RG, Weaver AL, Katusi SK. Wrien-Language Disorder among children with and without ADHD in populaon-based birth cohort. Pediatrics, 2011. 128: e605.

¨ Adi-Japha E, Landau YE, Frenkel L, Teicher M, Gross-Tsur V, Shalev RS. ADHD and Dysgraphia: Underlying Mechanisms. Cortex, 2007. 43:700-709.

¨ Eden GF and Chandan VJ. ADHD and Developmental Dyslexia. Annals Ny.Y Acad. Sci. 2008. 1145:316-327

¨ Keulers EH, et al. Methylphenidate improves reading performance in children with aenon deficit hyperacvity disorder and comorbid dyslexia: an unblinded clinical trial. Eur. J Paediatr Neurol. 2007. 11:21-8.

¨ Bental B and Tirosh E. The effects of methylphenidate on word decoding accuracy in boys with aenon- deficit/hyperacvity disorder. J Clin Psychopharmacol. 2008. 28: 89-92.

¨ Shafritz et al. The effects of methyphenodate on neural systems of aenon in aenon deficit hyperacvity disorder. 2004. 161:1990-1997.