White matter connectivity in uncinate fasciculus accounts for visual attention span in developmental dyslexia. (15th December 2022)

• Record Type: Journal Article
• Authors: Zhao, Jingjing; Song, Zujun; Zhao, Yueye; Thiebaut de Schotten, Michel; Altarelli, Irene; Ramus, Franck
• Is Part Of: Neuropsychologia. Number 177(2022)
• Publication Date: 2022-12-15
• Subjects: Developmental dyslexia -- Diffusion imaging -- Uncinate fasciculus -- Frontal aslant tract -- Visual attention span; UF Uncinate fasciculus -- FAT Frontal aslant tract -- HMOA Hindrance-modulated oriented anisotropy -- FA Fractional anisotropy -- DD Developmental dyslexia -- DTI Diffusion tensor imaging -- VAS Visual attention span; Neuropsychology -- Periodicals; Neurology -- Periodicals; Psychophysiology -- Periodicals; Neuropsychologie -- Périodiques; Neuropsychology; Periodicals; Electronic journals; 616.8
• DOI: 10.1016/j.neuropsychologia.2022.108414
• Languages: English
• ISSNs: 0028-3932

Abstract

Abstract: The present study aimed to investigate the role of connectivity disruptions in two fiber pathways, the uncinate fasciculus (UF) and the frontal aslant tract (FAT), in developmental dyslexia and determine the relationship between the connectivity of these pathways and behavioral performance in children with dyslexia. A total of 26 French children with dyslexia and 31 age-matched control children were included. Spherical deconvolution tractography was used to reconstruct the two fiber pathways. Hindrance-modulated oriented anisotropy (HMOA) was used to measure the connectivity of each fiber pathway in both hemispheres. Only boys with dyslexia showed reduced HMOA in the UF compared to control boys. Furthermore, HMOA of the UF correlated with individual differences in the visual attention span in participants with dyslexia. All significant results found in HMOA of the UF were verified in fractional anisotropy (FA) of the UF using standard diffusion imaging model. This study suggests a differential sex effect on the connectivity disruption in the UF in developmental dyslexia. It also indicates that the UF may play an essential role in the visual attention span deficit in developmental dyslexia. Highlights: Connectivity in the uncinate fasciculus is disrupted in developmental dyslexia. Connectivity disruption in the uncinate fasciculus only appears in dyslexic boys. Uncinate fasciculus accounts for the visual attention span in dyslexic children.