Palser-Miller-2022
Authors: Eleanor R. Palser, Zachary A. Miller, Abigail E. Licata, Nicole A. Yabut, Swati P. Sudarsan, Boon Lead Tee, Jessica A. Deleon, Maria Luisa Mandelli, Eduardo Caverzasi, Virginia E. Sturm, Robert Hendren, Katherine L. Possin, Bruce L. Miller, et al..
Article: Visual and social differences in dyslexia: deep phenotyping of four cases with spared phonology.
Publication: Neurocase (Taylor and Francis). Published online: 30 Nov 2022 2022 | DOI: 10.1080/13554794.2022.2145905
ABSTRACT
Diagnostic criteria for dyslexia describe specific reading difficulties, and single-deficit models, including the phonological deficit theory, have prevailed. Children seeking diagnosis, however, do not always show phonological deficits, and may present with strengths and challenges beyond reading. Through extensive neurological, neuropsychological, and academic evaluation, we describe four children with visuospatial, socio-emotional, and attention impairments and spared phonology, alongside long-standing reading difficulties. Diffusion tensor imaging revealed white matter alterations in inferior longitudinal, uncinate, and superior longitudinal fasciculi versus neurotypical children. Findings emphasize that difficulties may extend beyond reading in dyslexia and underscore the value of deep phenotyping in learning disabilities.
Eleanor R. Palser, Zachary A. Miller, Abigail E. Licata, Nicole A. Yabut, Swati P. Sudarsan, Boon Lead Tee, Jessica A. Deleon, Maria Luisa Mandelli, Eduardo Caverzasi, Virginia E. Sturm, Robert Hendren, Katherine L. Possin, Bruce L. Miller, Maria Luisa Gorno Tempini & Christa Watson Pereira (2022) Visual and social differences in dyslexia: deep phenotyping of four cases with spared phonology, Neurocase, DOI: 10.1080/13554794.2022.2145905
A focus on mapping the language profiles of individuals with dyslexia has undoubtedly contributed tremendously to our understanding of the academic challenges these individuals face, and potential remediation strategies for these challenges. This focus has been constrained, however, by the prevailing single deficit accounts of the condition and the narrow focus on “pure” cases and those with a primary phonological deficit.
Here, we describe a series of four children that show both marked reading difficulties commensurate with the diagnostic criteria for dyslexia, in addition to several other strengths and challenges not included in the diagnostic criteria.
Strikingly, although reading was the primary presenting concern for these children, for three of the four cases, visuospatial performance was poorer than the lowest reading score. Moreover, all cases showed phonological awareness, rapid automized naming, and memory for words within the average to superior range, which stands counter to the notion that these skills are the core underlying deficit(s) in dyslexia. All four cases had developmental concerns prior to the second grade, most frequently in the form of motor delay.
These cases also showed other characteristics that are not part of the diagnostic criteria for dyslexia. All experienced sensory sensitivities, psychomotor difficulties, and socio-emotional challenges, particularly withdrawal, reduced functional communication, and signs of impaired emotion regulation.
Specifically, compared to neurotypical children, we observed greater rightward asymmetry in volume of the ILF in children with atypical dyslexia, alongside greater FA bilaterally in the SLF-TP, and reduced FA in the left uncinate fasciculus. The uncinate fasciculus contributes to a ventral reading network (Schlaggar & McCandliss, 2007), connecting the anterior temporal lobe to the frontal lobe (Catani et al., 2002)
