Eye Movement And Neural Mechanism Research On Individual Differences In Vocabulary Processing In Chinese Reading And Its Educational Implication

The efficiency of lexical processing varies with individual development and aging.However,whether there are also essential differences in lexical processing efficiency among skilled adult readers remains to be investigated in Chinese reading.Previous studies on eye movements provided evidence on individual differences in lexical processing among adult readers during Chinese reading.The eye movement behavior in reading is based on complex neural mechanism.Previous studies have found the basis of the resting-state functional connectivity of the brain on individual differences on first-pass fixation time in Chinese reading.However,the neural basis of the individual differences in lexical processing on eye movements is unclear.The present study aimed to investigated this issue.In specific,the present study combined the eye-tracking technology and the f MRI technology and manipulated two important lexical attributes(i.e.,word frequency and predictability)through two experiments to investigate how individual differences on word frequency effect and predictive effect on eye movement measures are related to the brain structure imaging.A same group of 76 college students were recruited in both experiments.The Eye Link1000 plus tower eye tracker was used to record eye movements of participants,and the Siemens 3t Prisma scanner was used to record the whole brain imaging data of the participants.In Experiment1,the word frequency of two-word target words in sentence was manipulated,and the fixation times and fixation counts was used to calculate the effect size of word frequency effect as indicators of the individual word processing efficiency.Then,the correlation between the word frequency effect size and the gray matter volume of each participant was analyzed to explore the neural basis of individual differences in word processing efficiency.The Experiment 2 manipulated the predictability of two-word target words in sentence.The experimental procedure was the same as experiment 1,and the correlation between the predictive effect size and the gray matter volume of each participant was analyzed.The results showed that the word frequency effect was significantly positively correlated with the gray matter volume of the left superior parietal lobule.To be specific,the greater the difference in the regression path time between high frequency words and low frequency words,the greater the word frequency effect,and the larger the gray matter volume of the left superior parietal lobule.The predictive effect size on first fixation count was negatively correlated with the gray matter volume of the bilateral insular cortex,respectively.Specifically,the greater the difference between the first fixation counts of high and low prediction words,the greater the predictive effect,and the smaller the gray matter volume of the left and right insular cortex.In conclusion,in Chinese reading,the individual differences in lexical processing on eye movements is significantly correlated with gray matter volume of the left parietal lobule,bilateral insular cortex,which providing neural evidence in supporting the differential view in adult reading.Our finding are supposed to be helpful to understand the eye movement behavior and cognitive neural basis of individual differences in lexical processing during Chinese reading,which might be useful to guide word learning and to improve reading proficiency for Chinese students or learners.