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bioRxiv · 10.1101/2024.12.24.630007

Atypical Visual Selective Attention in Children with Dyslexia: Evidence from N2pc and PD

Liu, H.·Sun, Y.·Wang, Z.·Guo, J.·Song, Y.·Meng, X.
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Abstract

Efficient visual attention is fundamental to the development of reading abilities. Previous studies have identified visual attention impairments in individuals with dyslexia, particularly in visual attention span and sluggish attention shifting. However, findings regarding basic visual selective attention remain controversial. To address this issue, the present study provides event-related potential (ERP) evidence to verify whether children with developmental dyslexia (DD) suffered from deficits in visual selective attention. A pop-out visual search task was used to examine visual attentional patterns to a lateral target in 66 children (33 children with DD and 33 typically developing (TD) children) using electroencephalography. Compared to TD children, children with DD showed a larger and prolonged P1 component, as well as a larger target-evoked N2pc component. The larger P1 amplitude was associated with lower reading fluency while the larger N2pc amplitude was associated with poor reading comprehension performance. Interestingly, the target-elicited N2pc was followed by positivity (PD component) in TD children but not in children with DD; however, the N2pc amplitude was correlated with the PD amplitude in children with DD. Children with DD show immature early attentional processing and may have an imbalance in the regulation of visual selective attention between attentional selection and suppression. Our findings provide ERP evidence for interpreting the underlying neural mechanism of visual selective attention in children with DD and may offer a new perspective for exploring the mechanism of visual attention deficits in dyslexia. Research HighlightsO_LIIn a pop-out visual search task, children with dyslexia exhibited a larger N2pc and an absent PD component. C_LIO_LIThe absence of the PD component in children with dyslexia may be associated with their larger N2pc amplitudes. C_LIO_LIN2pc amplitude is associated with reading ability in children with dyslexia. C_LIO_LIChildren with dyslexia need to allocate more resources towards the target but also struggle to disengage from the attended location. C_LI

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Liu, H., Sun, Y., Wang, Z., Guo, J., Song, Y., Meng, X.. 2024-12-24. Atypical Visual Selective Attention in Children with Dyslexia: Evidence from N2pc and PD. https://doi.org/10.1101/2024.12.24.630007

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