title: Involvement of the right hemisphere in reading comprehension: a DTI study.
abstract: The Simple View of reading emphasizes the critical role of two factors in normal reading skills: word recognition and reading comprehension. The current study aims to identify the anatomical support for aspects of reading performance that fall within these two components. Fractional anisotropy (FA) values were obtained from diffusion tensor images in twenty-one typical adolescents and young adults using the tract based spatial statistics (TBSS) method. We focused on the arcuate fasciculus (AF) and inferior longitudinal fasciculus (ILF) as fiber tracts that connect regions already implicated in the distributed cortical network for reading. Our results demonstrate dissociation between word-level and narrative-level reading skills: the FA values for both left and right ILF were correlated with measures of word reading, while only the left ILF correlated with reading comprehension scores. FA in the AF, however, correlated only with reading comprehension scores, bilaterally. Correlations with the right AF were particularly robust, emphasizing the contribution of the right hemisphere, especially the frontal lobe, to reading comprehension performance on the particular passage comprehension test used in this study. The anatomical dissociation between these reading skills is supported by the Simple View theory and may shed light on why these two skills dissociate in those with reading disorders.
authors.affiliation: Pediatric Neuroimaging Research Consortium, Cincinnati, OH, USA. Electronic address: Tzipi.Horowitz-Kraus@cchmc.org.
authors.forename: Tzipi
authors.initials: T
authors.lastname: Horowitz-Kraus
authors.affiliation: Pediatric Neuroimaging Research Consortium, Cincinnati, OH, USA; Department of Biomedical Engineering, University of Cincinnati, Cincinnati, OH, USA.
authors.forename: Yingying
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Speech, Language, & Hearing Sciences, The University of Arizona, Tucson, AZ, USA.
authors.forename: Elena
authors.initials: E
authors.lastname: Plante
authors.affiliation: Pediatric Neuroimaging Research Consortium, Cincinnati, OH, USA; Department of Biomedical Engineering, University of Cincinnati, Cincinnati, OH, USA; Department of Radiology, Cincinnati Children׳s Hospital, Cincinnati, OH, United States.
authors.forename: Scott K
authors.initials: SK
authors.lastname: Holland
mesh_terms: D000293:Adolescent; D001921:Brain / Q000033:anatomy & histology*; D032882:Comprehension; D056324:Diffusion Tensor Imaging; D017352:Echo-Planar Imaging; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007807:Language Tests; D008297:Male; D033262:Narration; D009483:Neuropsychological Tests; D011932:Reading; D014825:Vocabulary; D055815:Young Adult
keywords: Arcuate fasciculus; Diffusion tensor imaging; Inferior longitudinal fasciculus; Reading; Reading comprehension