title: Reading Comprehension in Boys with ADHD: The Mediating Roles of Working Memory and Orthographic Conversion.
abstract: Reading comprehension difficulties in children with ADHD are well established; however, limited information exists concerning the cognitive mechanisms that contribute to these difficulties and the extent to which they interact with one another. The current study examines two broad cognitive processes known to be involved in children's reading comprehension abilities-(a) working memory (i.e., central executive processes [CE], phonological short-term memory [PH STM], and visuospatial short-term memory [VS STM]) and (b) orthographic conversion (i.e., conversion of visually presented text to a phonological code)-to elucidate their unique and interactive contribution to ADHD-related reading comprehension differences. Thirty-one boys with ADHD-combined type and 30 typically developing (TD) boys aged 8 to 12 years (M = 9.64, SD = 1.22) were administered multiple counterbalanced tasks assessing WM and orthographic conversion processes. Relative to TD boys, boys with ADHD exhibited significant deficits in PH STM (d = -0.70), VS STM (d = -0.92), CE (d = -1.58), and orthographic conversion (d = -0.93). Bias-corrected, bootstrapped mediation analyses revealed that CE and orthographic conversion processes modeled separately mediated ADHD-related reading comprehension differences partially, whereas PH STM and VS STM did not. CE and orthographic conversion modeled jointly mediated ADHD-related reading comprehension differences fully wherein orthographic conversion's large magnitude influence on reading comprehension occurred indirectly through CE's impact on the orthographic system. The findings suggest that adaptive cognitive interventions designed to improve reading-related outcomes in children with ADHD may benefit by including modules that train CE and orthographic conversion processes independently and interactively.
authors.affiliation: Department of Psychology, University of Central Florida, 4111 Pictor Lane Psychology Bldg 99, Orlando, FL, 32816, USA.
authors.forename: Lauren M
authors.initials: LM
authors.lastname: Friedman
authors.affiliation: Department of Psychology, University of Central Florida, 4111 Pictor Lane Psychology Bldg 99, Orlando, FL, 32816, USA. mdrapport@gmail.com.
authors.forename: Mark D
authors.initials: MD
authors.lastname: Rapport
authors.affiliation: Department of Psychology, Florida International University, 11200 S.W. 8th St. AHC 1, Room 239, Miami, FL, 33199, USA.
authors.forename: Joseph S
authors.initials: JS
authors.lastname: Raiker
authors.affiliation: Department of Psychology, University of Central Florida, 4111 Pictor Lane Psychology Bldg 99, Orlando, FL, 32816, USA.
authors.forename: Sarah A
authors.initials: SA
authors.lastname: Orban
authors.affiliation: Department of Psychology, University of Central Florida, 4111 Pictor Lane Psychology Bldg 99, Orlando, FL, 32816, USA.
authors.forename: Samuel J
authors.initials: SJ
authors.lastname: Eckrich
mesh_terms: D001289:Attention Deficit Disorder with Hyperactivity / Q000503:physiopathology*; D002648:Child; D032882:Comprehension / Q000502:physiology*; D056344:Executive Function / Q000502:physiology*; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D010364:Pattern Recognition, Visual / Q000502:physiology*; D011932:Reading
keywords: Attention-deficit/hyperactivity disorder; Executive functions; Orthographic conversion; Reading comprehension; Working memory