Development of lexical-semantic language system: N400 priming effect for spoken words in 18- and 24-month old children

► The N400 priming effect was observed in 24-but no in 18-month-olds. ► The N400 effect was observed at 18-month-olds with a high vocabulary size. ► Words are taxonomically organized in the lexicon of children at the age of 2 years.