Cross-Cultural Investigation of The Relation Between Attentional Disengagement and Reading Performance: Behavioral and Electrophysiological Evidence from Chinese and Italian

Developmental dyslexia is one of the most common learning disorders in children and adolescents. Revealing the causes of dyslexia is necessary for intervention on this disorder. Previous studies have shown that inefficient attention orienting is a causal factor for reading difficulties in dyslexics, and it can be indexed by sluggish inhibition of return. However, a fundamental understanding of the neural bases of inefficient attention disengagement remains unclear. The present thesis investigated the neural mechanism underlying the attention disengagement process and its relation with reading performance using behavioral and electrophysiological methods. Chapter 1 measured several electrophysiological indices while Chinese children, both dyslexic and typically developing, were asked to detect a target stimulus preceded by an uninformative cue stimulus in the classic cue-target paradigm. The possible relation between stimulus-locked ERP activity and reading skills was also examined to further understand how efficiency of attention disengagement affects reading. These studies considered both cue-locked and target-locked ERP activities to examine the neural mechanism of attention disengagement. Chapter 2 examined neural oscillations related to attention disengagement as well as resting-state EEG activity in different frequency ranges in children with and without dyslexia. The relation between activation patterns in several frequency ranges and reading skills indicated that neural indices of attention disengagement and resting-state activity are predictive of reading performance. In the following Chapters 3 and 4, the neural mechanisms underlying attention disengagement was investigated in Italian young adults. Chapter 3 investigated both cue-evoked and target-evoked ERP activities in the cue-target task, and also examined the correlation between neural cueing effect, attention disengagement efficiency, and reading skills. In Chapter 4, neural oscillations related to target-evoked as well as resting-state EEG activity in different frequency ranges were examined on the Italian young adults, to provide a new insight on the correlation between neural oscillations in stimulus-locked activity and reading performance. Overall, these studies revealed the different electrophysiological parameters indexing the efficiency of attention disengagement for both children and adults, providing multiple signatures of stimulus-locked neural activity during attention shifting. Importantly, the parallel results from Chinese and Italian participants shows the generality of these findings and demonstrates the influence of attention shifting mechanisms on reading performance in both alphabetic and logographic scripts. More importantly, this study suggests that intervention targeting attention disengagement efficiency might be a fruitful approach for improving reading skills in dyslexia.