ABSTRACT

The latencies o f the P I00, N200, and N350 were slightly earlier for the 20-month-olds than for the 13-to 17-month-olds. The duration o f the late negative com ponent was som ewhat longer, by 300 ms, for the 13-to 17-months-olds than for the 20-month-olds. There also were marked age-related differences in the distribution o f ERP responsiveness to the different types o f words. A t 13 to 17 months of age ERP differences to com prehended and unknown words were bilateral and widely distributed, whereas at 20 months these differences were limited to temporal and parietal regions of the left hemisphere. ERP differences to com pre­ hended versus backward words were bilaterally distributed for both groups. Only the 20-m onth-olds showed N200 and N350 am plitude differences to unknown versus backward words.