Authors: Rachel L. Eggleston, Rebecca A. Marks, Xin Sun, Chi-Lin Yu, Kehui Zhang, Nia Nickerson, Xiaosu Hu, Valeria Caruso. Adriene Beltz, Ioulia Kovelman.
Article: Lexical morphology as a source of risk and resilience for learning to read with dyslexia: An fNIRS investigation.
Publication: Preprint Created: May 08, 2023 2023 | DOI: 10.31234/osf.io/nt957
Purpose: To understand the role of meaning-based skills in learning to read with dyslexia, we examined the neuro-cognitive bases of lexical morphology in children of varied reading abilities.
Method: Children completed auditory morphological and phonological awareness tasks during functional near-infrared spectroscopy neuroimaging. We first examined the relation between lexical morphology and phonological processes in typically developing readers (Study 1, N = 66, Mage = 8.39), followed by a more focal inquiry into lexical morphology processes in dyslexia (Study 2, N = 50, Mage = 8.62). We then conducted a data-driven network analysis to examine functional connectivity during lexical morphology processes in all participants (Study 3, N = 91, Mage = 8.77).
Results: Typical readers exhibited stronger engagement of language neurocircuitry during the morphology task relative to the phonology task, suggesting that morphological analyses involve a synthesis of multiple components of sublexical processing. This effect was stronger for more analytically complex derivational morphemes (like+ly) relative to more semantically transparent free root morphemes (snow+man). In contrast, children with dyslexia exhibited stronger activation during the free root relative to derivational morpheme conditions, possibly because children with dyslexia use semantic information to boost word recognition. Data-driven and person-specific functional connectivity analyses revealed two groups of readers with either denser fronto-temporal or temporal-only connections. Stronger readers with and without dyslexia were more likely to fall into the fronto-temporal group.
Conclusions: This study informs literacy theories by identifying an interaction between reading ability, word structure, and the way that the developing brain learns to recognize words in speech and in print.
Eggleston, R. L., Marks, R. A., Sun, X., Yu, C., Zhang, K., Nickerson, N., … Kovelman, I. (2023, May 8). Lexical morphology as a source of risk and resilience for learning to read with dyslexia: An fNIRS investigation. https://doi.org/10.31234/osf.io/nt957