Infants’ understanding of false labeling events: the referential roles of words and the speakers who use them Melissa A. Koenig a, * , Catharine H. Echols b a Harvard University, Cambridge, MA, USA b The University of Texas, Austin, TX, USA Received 22 August 2000; received in revised form 23 September 2002; accepted 2 December 2002 Abstract The four studies reported here examine whether 16-month-old infants’ responses to true and false utterances interact with their knowledge of human agents. In Study 1, infants heard repeated instances either of true or false labeling of common objects; labels came from an active human speaker seated next to the infant. In Study 2, infants experienced the same stimuli and procedure; however, we replaced the human speaker of Study 1 with an audio speaker in the same location. In Study 3, labels came from a hidden audio speaker. In Study 4, a human speaker labeled the objects while facing away from them. In Study 1, infants looked significantly longer to the human agent when she falsely labeled than when she truthfully labeled the objects. Infants did not show a similar pattern of attention for the audio speaker of Study 2, the silent human of Study 3 or the facing- backward speaker of Study 4. In fact, infants who experienced truthful labeling looked significantly longer to the facing-backward labeler of Study 4 than to true labelers of the other three contexts. Additionally, infants were more likely to correct false labels when produced by the human labeler of Study 1 than in any of the other contexts. These findings suggest, first, that infants are developing a critical conception of other human speakers as truthful communicators, and second, that infants understand that human speakers may provide uniquely useful information when a word fails to match its referent. These findings are consistent with the view that infants can recognize differences in knowledge and that such differences can be based on differences in the availability of perceptual experience. q 2003 Elsevier Science B.V. All rights reserved. Keywords: Infants; False labeling; Language acquisition; Referential intent M.A. Koenig, C.H. Echols / Cognition 87 (2003) 179–208 179 Cognition 87 (2003) 179–208 www.elsevier.com/locate/cognit 0010-0277/03/$ - see front matter q 2003 Elsevier Science B.V. All rights reserved. doi:10.1016/S0010-0277(03)00002-7 * Corresponding author. Harvard Graduate School of Education, 502 Larsen Hall, Appian Way, Cambridge, MA 02138, USA. E-mail address: melissa_koenig@gse.harvard.edu (M.A. Koenig).