Using the N400 event-related potential to study word learning from context in children from low- and higher-socioeconomic status homes.

Children from low-socioeconomic status (SES) homes have significantly smaller vocabularies than their higher-SES peers, a gap that increases over the course of the school years. One reason for the increase in this vocabulary gap during the school years is that children from low-SES homes learn fewer words from context than their higher-SES peers. To better understand how the process of word learning from context might differ in children related to SES, we investigated changes in the N400 event-related potential (ERP) as children from low- and higher-SES homes learned new words using only the surrounding linguistic context. There were no differences in the N400 response to known words related to SES. In response to the target word being learned, children from higher-SES homes, like adults in previous studies, exhibited an attenuation of the N400 across exposures as they attached meaning to it. Children from low-SES homes did not show this same attenuation. These findings support previous work showing that children from low-SES homes may have differences or more variability in the neural components supporting language processing, and they extend previous work to illustrate how this variability may relate to word learning and, ultimately, vocabulary growth.