Grade-related changes in event-related potentials (ERPs) in primary school children: Differences between two reading tasks.

Recorded event-related potentials (ERPs) from the left and right temporal and parietal sites during word reading in 39 boys and 30 girls who were followed over 3 yrs, starting at Grade 1. Task 1 required Ss to read repeatedly presented words; Task 2 consisted of a series of different words, with each word being presented only once. All ERP components showed changes in amplitude as a function of grade: P240, N530, the parietal N150, and SW all decreased, whereas the temporal N360 and slow-wave (SW) both increased. Proficient readers showed larger SW and N360 asymmetries and shorter vocal response times than did less proficient readers. A positive relationship was found between reading performance and ERP amplitudes over the left temporal hemisphere at Grades 2 and 3, particularly in the single word reading task. Results are discussed in terms of age-related changes in right and left hemisphere functions involved in learning to read.