How children block learning from ignorant speakers.

Preschool children typically do not learn words from ignorant or unreliable speakers. Here, we examined the mechanism by which these learning failures occur by modifying the comprehension test procedure that measures word learning. Following lexical training by a knowledgeable or ignorant speaker, 48 preschool-aged children were asked either a standard comprehension test question (i.e., "Which one is the blicket") or a question about the labeling episode (i.e., "Which one did I say is the blicket"). Immediately after training, children chose the object labeled by an ignorant speaker when asked the episode question, but not when asked the semantic question. However, the advantage for episode questions disappeared when the same children were asked after a brief delay. These findings show that children encode their experiences with ignorant speakers, but do not form semantic representations on the basis of those experiences.