Yale University School of Medicine An fMRI comparison of reading disabled adolescents with and without general cognitive difficulty Nicole Landi 1,2,3, Stephen J. Frost 3, W. Einar Mencl 3, Rebecca Sandak 3 & Kenneth R. Pugh 2,3 1 Yale Child Study Center; 2 Yale University Scool of Medicine & 3 Haskins Laboratories Background Neurobiological circuit associated with skilled reading: TASKS Behavioral assessments: - Woodcock-Johnson III Tests of Achievement (WJ; Woodcock, McGrew, & Mather, 2001) -Tests of Word Reading Efficiency (TOWRE; Torgesen, Wagner & Rashotte, 1999) -Comprehensive Test of Phonological Processing (CTOPP; Wagner, Torgesen, & Rashotte, 1999) -Peabody Picture Vocabulary Test (PPVT; Dunn & Dunn, 1997) -Wechsler Abbreviated Scale of Intelligence (WASI; The Psychological Corporation, 1999). fMRI task: Event-related fMRI: match/mismatch judgment via button press to auditorally and visually presented targets to a picture cue Mismatched targets include: Printed: words, pseudowords, consonant strings, semantically related words & Spoken: words, pseudowords Study Methods fMRI Data Acquisition and Analysis Study Results: Behavioral data fMRI Results:RD-DfMRI Results: RD-A Participants Full sample: 25 RD children, 13 RD-D, 12 RD-A Age M = 8.2 years fMRI Sample: 7 RD children, 5, RD-D, 2RD-A ALL RD > 90 SS on reading composite (WJ Spelling, Word Attack and passage comprehension) RD-D > 90 on WASI performance IQ RD-A >90 on WASI peformance IQ Funding was provided by NICHD R03 HD053409, Landi (PI) & NICHD RO1 HD Pugh (PI) We acquired functional images on a Siemens 1.5T Sonata MRI scanner at the Yale University School of Medicine. Subjects recieved 40 trials of each condition across 10 scan runs. Subject activations to the base stimulus conditions were analyzed across subjects with ANOVA. IFG MTG/ITG OT/ VWFA SMG/STG AG Individuals with reading disability (RD) show less activation in the posterior left hemisphere (LH) reading circuit relative to typically developing readers across a variety of reading tasks (e.g., Pugh et al. 2000) A substantial number of individuals with RD do not meet formal discrepancy criteria. Many RD readers also have difficulty in one or more other academic skill domains. In the current study, we explore the question of functional subtypes in RD, examining: Reading disability with achievement discrepancy (RD-D) Reading disability with poor general achievement (RD-A). We ask: What are the behavioral and neurobiological markers associated with with RD-A vs. RD-D? time RD-A - RD-D, printed words RD-A- RD-D, spoken words Yellow = RD-A> RD-D; Purple = RD-D>RD-A p =.005, FDR correcte; slice numbers = MNI Z coordinates L L PIQ RD-A < RD-D, p <.01; Reading RD-D = RD-A Conclusions Behavior: RD-D and RD-A have comparable performance on many measures of reading and other academic skills. They differ significantly only on measures of IQ and vocabulary. fMRI: For print, RD-A children recruit the parahippocampal region suggesting greater reliance on general memory function for reading. RD-D show greater bilateral temporal activity (STG/MTG), as well as several other RH regions suggesting possible use of semantics to compensate for poor phonological/decoding skills. For spoken words, RD-A children show greater activation in STG relative to RD-D, suggesting that auditory- lexical connections maybe weaker for RD-A children. We also observed greater activity in the occipitotemporal (OT) region for the RD-A group for both modalities; this area is typically underactivated in RD children relative to TD children. This suggests that this part of the LH reading circuit is more intact in RD-A children relative to RD-D children. The only significant difference we observed was for PPVT performance; RD-D >RD A, p =.02 LH OT bilateral STG/MTG Parahippocampal gyrus Anterior cingulate STG/ Wernicke’s LH STG/MTG RH IFG bilateral STG RH extrastriate & Posterior cingulate * * Identification of RD-A and RD-D Subtests of reading and academic skills