Children With Reading Difficulty Rely on Unimodal Neural Processing for Phonemic Awareness

Abstract

Phonological awareness skills in children with reading difficulty (RD) may reflect impaired automatic integration of orthographic and phonological representations. However, little is known about the underlying neural mechanisms involved in phonological awareness for children with RD. Eighteen children with RD, ages 9–13, participated in a functional magnetic resonance imaging (fMRI) study designed to assess the relationship of two constructs of phonological awareness, phoneme synthesis, and phoneme analysis, with crossmodal rhyme judgment. Participants completed a rhyme judgment task presented in two modality conditions; unimodal auditory only and crossmodal audiovisual. Measures of phonological awareness were correlated with unimodal, but not crossmodal, lexical processing. Moreover, these relationships were found only in unisensory brain regions, and not in multisensory brain areas. The results of this study suggest that children with RD rely on unimodal representations and unisensory brain areas, and provide insight into the role of phonemic awareness in mapping between auditory and visual modalities during literacy acquisition.

How Learning to Read Changes the Listening Brain

“…Further support for a key role of the superior temporal cortex in learning to read comes from developmental neuroimaging studies showing that the strength and/or extent of speech evoked responses in this region is associated with children’s reading level ( Parviainen et al, 2011 ; Brennan et al, 2013 ; Conant et al, 2014 ; Lohvansuu et al, 2018 ), and phonological skills ( Turkeltaub et al, 2003 ; Conant et al, 2014 ; Bonte et al, 2016 ; Randazzo et al, 2019 ). Moreover, children with dyslexia ( Schulte-Körne et al, 1998 ; Bonte and Blomert, 2004 ; Frey et al, 2019 ; Schaadt and Männel, 2019 ; Gu and Bi, 2020 ; Virtala et al, 2020 ), or at familial risk for developing dyslexia ( Vandermosten et al, 2020 ) may show reduced or less discriminable auditory cortical responses to speech.…”

The Connectivity Fingerprints of Highly-Skilled and Disordered Reading Persist Across Cognitive Domains

“…Relative to controls, dyslexics under-activate the left temporo-parietal cortex (Temple et al, 2001), and show delayed specialization in the ventral visual object processing stream for visual word processing (van der Mark et al, 2009). Under-activation in this network of regions has been argued to reflect failure of audiovisual integration processing (Blau et al, 2010;Randazzo et al, 2019) and failure to engage lexical-semantic representations (Richlan et al, 2009). Relative to controls, dyslexics over-activate the right occipitotemporal cortex and anterior inferior temporal gyrus, which has been suggested to reflect compensatory activation (Shaywitz and Shaywitz, 2005).…”