Slide Slam N10
Neural Activation during Phonological Processing in Primary-School Children with Limited Reading Experience: Insights from Rural Côte d’Ivoire
Xinyi Yang1, Shakhlo Nematova2, Kaja Jasińska1,3; 1University of Toronto, 2University of Delaware, 3Haskins Laboratories
Introduction: Phonological awareness (PA), the ability to recognize and manipulate language sounds, is both an important predictor and outcome of reading skill. With more reading experience, PA improves, and left-hemisphere (LH) temporo-parietal regions (e.g., LSTG) that support phonological processing become increasingly engaged during both speech and reading. However, little is known about the reciprocal relation between PA and reading across development in the absence of consistent reading experience. Individuals who did not learn to read (i.e. illiterate adults) show poorer PA relative to their literate peers. Individuals who learn to read in adulthood struggle to achieve fluency, suggesting that reading experience in childhood, a period of greater brain plasticity and sensitivity to phonological information, best supports the reciprocal development of PA and reading. Here, we ask how neural activation patterns in the left temporo-parietal cortex during phonological processing relate to reading skills in children with little reading experience. We focus on rural Côte d’Ivoire, where children have inconsistent reading experience (i.e due to starting school at an older age and poor access to quality education). We hypothesize that activation in the left temporo-parietal cortex during phonological processing corresponds to children’s reading experience and reading skills. Methods: Sixty-nine children (7-13 years, Mage=10.4, SDage=1.53) completed a French rhyme judgment task while undergoing fNIRS neuroimaging, and a French letter, word, and pseudoword reading task. The rhyme judgment task (a measure of PA) required children to listen to randomly-presented word pairs, and determine whether the word pair rhymed or not. We used AnalyzIR toolbox to estimate the effects of rhyming vs. non-rhyming word pairs, reading skill, and their interaction in the prefrontal and bilateral temporo-parietal cortices with a linear mixed effects model. Behavioral Results: Children’s accuracy was above chance for rhyme judgement, and higher for non-rhyming versus rhyming word pairs. Children’s reaction time was not significantly influenced by condition. Overall, reading skill levels were very low. Neuroimaging Results: We found a significant main effect of reading skill; higher reading scores were associated with greater activation mainly in the left temporo-parietal cortex. Importantly, we found a significant interaction between rhyming condition and reading skill. Neural activation in bilateral temporal cortex (BA21/40/48) was greater for non-rhyming words versus rhyming words for children at all reading skill levels. However, children with lower reading scores (i.e., 1SD below mean) showed greater activation in the IFG and DLPFC (BA10/45/46) for non-rhyming versus rhyming word pairs. Conclusion: Our results support our hypothesis; greater activation in the left temporo-parietal cortex was associated with better reading skills. However, we found that phonological processing is supported by additional prefrontal regions in less-skilled readers, suggesting that additional cognitive resources may support phonological processing. Our findings suggest that in the absence of consistent access to quality education, children with limited reading experience may ‘miss out’ on the reciprocal interaction between phonological processing and reading, which in turn shapes how language is processed in the brain.